Crucial p1 review: Crucial P1 NVMe SSD Review: QLC Flash Gone Mild (Updated) — Tom’s Hardware

Crucial P1 NVMe SSD Review: QLC Flash Gone Mild (Updated) — Tom’s Hardware

Tom’s Hardware Verdict

Crucial’s 500GB P1 packs three times the sequential performance of your average SATA based SSD, and brings decent 4K random performance, but is still a bit slower than competitors in application tests, even with its large SLC write cache. Even after steep price cuts, we recommend looking into other options unless the price drops even more

  • Poor direct to TLC write speed

  • Lower than average application performance

  • Write endurance rated to just 100TBW

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QLC Flash Gone Mild

7/15/19 Update: We’ve updated this article with new testing for the 500GB Crucial P1, as well as tweaked parts of the review to reflect current pricing.

Crucial’s P1 is the company’s very first NVMe SSD, but it is almost identical to the Intel SSD 660p we recently reviewed that came out around the same time. Just like the 660p, the P1 features Micron’s latest 64-layer 3D QLC flash and a Silicon Motion NVMe SSD controller.

The P1 breaks the SATA 6Gb/s barrier with its NVMe interface and delivers sequential throughput of up to 2/1.7 GB/s read/write, but we found that its real-world application performance is similar to the company’s SATA MX500 SSD. Coupled with higher-than-anticipated launch pricing, the P1 was a tough sell in the ultra-competitive SSD market when it was brand-new. Its street price has slid down rather dramatically in the last several months, but so has that of its silicon sibling, the Intel 660p, as well as other competing drives. So despite lower prices the P1 is still tough to recommend, unless you see it on a sweet sale that brings the price down even further.

Crucial P1 NVMe SSD ( (Image credit: Tom’s Hardware))

Crucial is the well-established consumer-facing brand of Micron, which is one of the few manufacturers of NAND flash. Being part of a NAND manufacturer ultimately means cheaper flash costs, and over the years Micron has passed that advantage to its customers by delivering competitive pricing and value. The company’s most recent SSD, the MX500, is the epitome of its ability to deliver value and reliability. It delivers enough performance to satisfy most, comes with multiple accessories, a robust feature set, and usually costs less than most of its mainstream competitors.

  • ADATA XPG GAMMIX S11 (960GB) (512GB Red) at Amazon for $46.99

That’s why anticipation has been building for the last year for Crucial’s first NVMe SSD. With the company’s track record, we surely thought it was going to be worth the wait. Well, today’s the day. We finally have the all new Crucial P1 in our hands, let’s see how it fares in our testing. 

Crucial P1 NVMe (1000GB)


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Crucial P1 NVMe (500GB)

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Product P1 500GB P1 1000GB P1 2000GB
Launch Pricing $109.99 $229.99 N/A
Street Price 7/11/19 $59.99 $99.99 N/A
Capacity (User / Raw) 500GB / 512GB 1000GB / 1024GB 2000GB / 2048GB
Form Factor M.2 2280 S3 (Single-Sided) M.2 2280 S3 (Single-Sided) M.2 2280 D2 (Double-Sided)
Interface / Protocol PCIe 3.0 x4 / NVMe 1.3 PCIe 3.0 x4 / NVMe 1.3 PCIe 3.0 x4 / NVMe 1.3
Controller Silicon Motion SM2263EN Silicon Motion SM2263EN Silicon Motion SM2263EN
DRAM DDR3 — 512MB DDR3 — 1GB DDR3 — 2GB
NAND Flash Micron 64L 3D QLC Micron 64L 3D QLC Micron 64L 3D QLC
Sequential Read 1,900 MB/s 2,000 MB/s 2,000 MB/s
Sequential Write 950 MB/s 1,700 MB/s 1,750 MB/s
Random Read QD1 90,000 IOPS 170,000 IOPS 250,000 IOPS
Random Write QD1 220,000 IOPS 240,000 IOPS 250,000 IOPS
Encryption N/A N/A N/A
Endurance 100 TBW 200 TBW 400 TBW
Part Number CT500P1SSD8 CT1000P1SSD8 CT2000P1SSD8
Warranty 5-Years 5-Years 5-Years

Crucial’s P1 series delivers up to 2/1. 75GB/s of sequential read/write throughput and up to 250,000/250,000 random read/write IOPS. As listed above, performance varies based upon the capacity of the drive. 

To achieve these speeds, the P1 uses Crucial’s Hybrid-Dynamic Write Acceleration technology. The P1’s firmware is exclusive to Micron, but the feature set is suspiciously similar to Intel’s SSD 660p, which also just happens to come with the same components.

Like most modern SSDs, the P1 has an SLC buffer that absorbs incoming data to boost performance. Crucial’s implementation takes a two-step approach to buffering. The drive has a fixed SLC buffer capacity of 5GB on the 500GB drive and 12GB on the 1TB model. In addition to the fixed buffer, the drive has a dynamic buffer that expands or contracts based upon the amount of data stored on the drive. This buffer can be located anywhere in the NAND array and consumes up to 14% of the usable capacity. That means the 500GB model should have a maximum buffer capacity of roughly 75GB and the 1TB model expands to 150GB.

The 500GB and 1000GB (1TB) drives are available at launch, but the 2TB model will come to market in November. Crucial’s MSRP of $109.99 for the 500GB model and $219.99 for the 1TB model are higher than the Intel SSD 660p and most SATA SSDs but undercuts most other NVMe SSDs.

Product TBW DWPD Warranty (Years)
Crucial P1 1TB 200 0.11 5
Intel SSD 660p 1TB 200 0.11 5
Corsair Force MP510 960GB 1700 0.93 5
Samsung 970 PRO 1TB 1200 0.66 5
Adata XPG GAMMIX S11/SX8200 960GB 640 0.35 5
Samsung 860/970 EVO 1TB 600 0.33 5
WD Black 1TB 600 0. 33 5
WD Blue 3D 1TB 400 0.37 3
Crucial MX500 1TB 360 0.2 5

The P1 comes with a lengthy five-year warranty, but as we expect from a QLC SSD, endurance comes up short. The P1 can absorb 100TB of data writes per 500GB of SSD capacity, which equates to 200TBW of endurance for the 1TB model. That’s the same endurance rating as Intel’s QLC-powered 660p. However, the competition has stepped up its game. Many 1TB class NVMe SSDs have endurance ratings of up to 600TBW. Some SSDs, like Corsair’s new MP510, offer more than eight times more endurance than the P1. Even Crucial’s own MX500 offers almost twice the endurance.

The P1 supports the NVMe low power states, so active power consumption is rated at just 100mW and stretches up to a maximum of 8W. It also has an impressive 80mW idle power consumption rating. The P1 also features power loss protection for data-at-rest and has a multi-step data integrity algorithm that protects against data loss. Crucial’s Adaptive Thermal Protection protects the components from overheating, and the RAIN (Redundant Array of Independent NAND) feature provides device-level data redundancy as a further layer of protection.

Unlike many new SSDs, including the Crucial MX500 and Intel SSD 660p, the Crucial P1 doesn’t support AES 256-bit hardware encryption.

Software and Accessories

Image 1 of 5

Crucial offers Acronis True Image HD software, which you can use to clone over your OS from your old drive or for backing up your data, and its Crucial Storage Executive software. The Storage Executive software provides SMART value monitoring, capacity monitoring, and performs firmware updates. The software also enables Crucial’s Momentum Cache, which is a RAM caching program that absorbs incoming random write data and flushes it to the drive as sequential data. That improves both performance and endurance.

A Closer Look

Image 1 of 7

The Crucial P1 is an NVMe 1.3 compliant SSD that communicates over a PCIe 3. 1 x4 connection. It comes in an M.2 2280 form factor and both the 500GB and 1TB models are single-sided, meaning all the components are on one side of the PCB. The 2TB model has components on both sides of the PCB (double-sided) and is a bit thicker. The SSD comes with a blacked-out PCB, which is a nice touch, but the white sticker on top doesn’t match the color scheme, and you can’t remove it without voiding your warranty.

The Crucial P1 comes equipped with the four-channel Silicon Motion SM2263EN controller that limits it to a maximum of 2GB/s of throughput. Silicon Motion’s pricier eight-channel SM2262/2262EN controllers are faster, but you’ll only find those on more expensive SSDs. 

The 1TB model comes with two NAND packages filled with 128GiB dies and has 931GB of usable capacity after formatting in Windows. The drive also uses a DDR3 buffer to accelerate the Flash Translation Layer (FTL). All models have 1MB of DRAM per 1GB of NAND. 


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Sean is a Contributing Editor at Tom’s Hardware US, covering storage hardware.

Crucial P1 NVMe SSD review: Fantastic value for the average user, but not for pros


It’s a very good performer until it runs out of cache.

By Jon Jacobi

Freelance contributor, PCWorld


At a Glance

Expert’s Rating


  • Market-leading cost per gigabyte
  • Very good performance until cache runs out


  • Sustained write speed plummets after secondary cache is exhausted
  • 500MB version writes half as fast as the 1TB

Our Verdict

This drive is very affordable. Stick with the 1TB version, whose performance is very good except during long writes (larger than about 4 percent of capacity). Not a drive for large data sets, but a great deal for the average user.

I regularly end bargain TLC SSD reviews with the advice “Don’t buy it unless it’s a lot cheaper than the competition. ” Until Crucial’s P1, no drive ever met that criteria. But the 17 cents per GB that the 1TB version will set you back is a good 8 cents cheaper than most of the competition. And, while it’s no blazing-fast Samsung 970  Pro, you don’t give up a ton of performance unless you regularly write 50GB (less with smaller capacities) or more. If you do, move along to another review.

Very fast, more expensive

Samsung 970 Pro M.2 NVMe SSD

The Crucial P1 is an x4 PCIE NVMe SSD that ships in the 2280 (22 mm wide, 80 mm long) form factor. The drive comes in 500GB and 1TB flavors that retail for $90 and $170 respectively. That’s a good $80 cheaper than most of the competition currently. They carry a 5-year warranty and are rated for 100TBW (TeraBytes Written) for every 500GB of capacity.


The P1 looks pretty much like any other 2280 NVMe/M.2 drive. It’s just cheaper.

That’s an extremely low TBW rating for an NVMe drive, but it’s no doubt part of the reason for the low price.   The scuttlebutt around the industry is that TBW ratings are worst-case scenarios that are generally exceeded by a large margin. And that’s still 54GB per day over the 5 years—more than most users are likely to write. And it is just writes—reading doesn’t affect longevity. 

Faster on big writes

Black SN750 NVMe SSD


Before I get to the results, please note that I tested the 1TB version of the drive. The 500MB version which I did not test, while cheaper, claims half the write performance. That’s a common phenomenon caused by having only half as many chips to spread the data across. It’s also likely to have less cache and fall prey to the slow TLC writes sooner. More on that in a paragraph or two.



The 1TB P1 actually passed all our standard tests, including the 48GB copies with flying colors, though it will never be mistaken for a Samsung 970 Pro, or even a 970 EVO. I’ve included the SATA drive to show just how much you’ll gain simply by moving to NVMe from SATA. Keep that in mind with all our NVMe reviews: Even the slowest is faster than SATA by a healthy margin.


No problem for the 1TB P1 when copying less than 50GB.

It was only during the 450GB write test, which we regularly run to see how things proceed when the cache runs out, that the drive slowed down—tragically.


A big problem when the 1TB P1 writes more than 50GB at a time.

By tragic, I’m talking roughly 95MBps, or more than a 1000-percent drop, as you can see in the image above. Ouch.



For normal everyday use, with NVMe’s stellar seek times and small file performance, the P1 remains an great bargain because of the price. But it’s not the drive for you if you regularly write large amounts of data. 


Though hardly best-of-breed, the P1’s copy times were still reasonable, and far better than the SATA drive we included for a technology comparison.


the budget drive

Price will out. The P1 is the first bargain SSD to that saves you enough money to forgive the occasional super-slow write. If you want fast sustained throughput when copying more than 50GB of data (or likely 25GB with the 500GB version), you’ll need to spend at least another $80 for WD’s Black SN750 NVMe. Your choice. 

This article was editing on November 30th, 2019 to note that the P1’s TBW ratings are very, not somewhat parsimonious. 

Author: Jon L. Jacobi, Freelance contributor

Jon Jacobi is a musician, former x86/6800 programmer, and long-time computer enthusiast. He writes reviews on TVs, SSDs, dash cams, remote access software, Bluetooth speakers, and sundry other consumer-tech hardware and software.

The Other Consumer QLC SSD

by Billy Tallison November 8, 2018 9:00 AM EST

  • Posted in
  • SSDs
  • Storage
  • Crucial
  • Micron
  • Silicon Motion
  • 3D QLC
  • SM2263



IntroductionAnandTech Storage Bench — The DestroyerAnandTech Storage Bench — HeavyAnandTech Storage Bench — LightSYSmark 2018Random PerformanceSequential PerformanceMixed Read/Write PerformancePower ManagementConclusion

The Crucial P1 SSD isn’t quite the first at anything, but it is still a very novel product. It is the second consumer SSD on the market to use four bit per cell (QLC) NAND flash memory, after the Intel SSD 660p. It’s the second QLC SSD from Micron, after their 5210 ION enterprise SATA SSD that started shipping to select partners in May (and is now starting to be more widely available).

More importantly however, it is the first consumer NVMe SSD that Micron has actually shipped. For all of their storied history in the SSD industry, Micron is pretty much the last SSD maker to enter the consumer NVMe market; and not for a lack of trying. The company’s first attempt at an NVMe drive, the 2016 Ballistix TX3, was ready to hit the market but was canceled when it became clear that it would not have been competitive. So this drive is a very important one for the company, despite the fact that its use of an NVMe/PCIe interface is hardly the most interesting aspect of the Crucial P1.

Under the hood, the Crucial P1 starts from the same basic ingredients as the Intel 660p: Intel/Micron 64-layer 3D QLC NAND and the Silicon Motion SM2263 controller. Micron has added their own firmware customization atop Silicon Motion’s work, and the design of the Crucial P1 differs from the Intel 660p in several aspects — so this is not a case of two brands selling the exact same reference design SSD.

Where the Intel 660p includes just 256MB of DRAM regardless of drive capacity, the Crucial P1 includes the same 1GB DRAM per 1TB NAND ratio that is used by most mainstream SSDs. This extra DRAM on the Crucial P1 should enable marginal improvements on benchmarks and workloads that touch large amounts of data, and probably allows a slight simplification to the drive’s firmware. The Crucial P1 also has slightly lower usable capacities, eg. 500GB instead of 512GB, so there’s a bit more spare area for the controller to work with. And whereas Intel’s 2TB 660p is still a single-sided M.2 module, the upcoming 2TB Crucial P1 will have NAND and DRAM on both sides.

Gallery: Crucial P1 1TB M.2 NVMe SSD

The rest of the architecture of the Crucial P1 follows the same general strategies as the Intel 660p. The SM2263 controller is the smaller four-channel design from Silicon Motion’s current generation, though it is a step above the DRAMless SM2263XT variant. The host interface is a PCIe 3.0 x4 link, but the Crucial P1 barely needs more than the PCIe 3.0 x2 link used by some competing entry-level NVMe controllers: peak sequential transfers for the P1 are only about 2GB/s.

Crucial P1 SSD Specifications
Capacity 500 GB 1 TB 2 TB
Form Factor Single-sided M.2 2280 Double-sided M.2 2280
Interface NVMe 1.3 PCIe 3.0 x4
Controller Silicon Motion SM2263
NAND Flash Micron 64L 3D QLC NAND
Sequential Read 1900 MB/s 2000 MB/s 2000 MB/s
Sequential Write 950 MB/s 1700 MB/s 1750 MB/s
Random Read 90k IOPS 170k IOPS 250k IOPS
Random Write 220k IOPS 240k IOPS 250k IOPS
SLC Write Cache (approximate) 5GB min
50GB max
12GB min
100GB max
24GB min
200GB max
Power Max 8W
Idle 2mW (PS4), 80mW (PS3)
Warranty 5 years
Write Endurance 100 TB
0. 1 DWPD
200 TB
0.1 DWPD
400 TB
0.1 DWPD
MSRP $109.99 (22¢/GB) $219.99 (22¢/GB) TBA

The use of QLC NAND means that the Crucial P1 is highly reliant on its SLC write cache to enable performance that can exceed what SATA SSDs provide. This is because the drive’s QLC NAND isn’t all that high performing on its own; it’s dense, but it takes longer to program a block than MLC or TLC NAND. TLC for that matter is cache-sensitive for similar reasons, but QLC in turn has cranked up the importance of cache sizes and caching algorithms another notch, as the performance delta between the cache and the actual storage has increased.

For Crucial’s P1 the SLC cache is variable in size, and on a nearly-empty drive the cache will be substantially larger than what is usually found on TLC SSDs. Consumer drives that use TLC NAND often try to limit the maximum size of their SLC caches in order to reduce the amount of background work necessary in the event that the SLC write cache should overflow. The Crucial P1 is designed to do as much as possible to avoid falling off that performance cliff, rather than attempt to mitigate the effects when it does happen.

When the SLC cache fills up, writes to the P1 get very slow. The P1 doesn’t bypass the cache when it is full, so everything written to the drive is written to SLC first before being folded into QLC blocks. (This helps the P1 offer similar partial power loss protection to the Crucial MX series of SATA SSDs.) The P1 also tends to keep data in SLC so it can serve as a read cache instead of aggressively folding data into QLC blocks during idle time.

All told, the caching strategy of the Crucial P1 maximizes performance and endurance for typical lightweight consumer/client storage workloads, but at the cost of performance on storage-intensive workloads. The P1 is definitely not the SSD to use in a workstation that regularly reads and writes datasets of many gigabytes, but it should be fine for more common desktop usage that is fairly read-heavy and only does multiple GB of writes on rare occasions such as when installing large software packages. This is in some sense just an amplification of the trends we saw as the SSD market moved from MLC to TLC NAND, but we do now have high-end TLC drives that can maintain high write speeds even after their SLC caches have filled. This is not true of the current two consumer QLC SSDs, and will probably always be a significant weakness of QLC SSDs.

The other major tradeoff to the Crucial P1’s use of QLC NAND is the lower write endurance compared to TLC SSDs. The P1 is rated for about 0.1 drive writes per day under a five-year warranty, while most consumer SSDs are rated for 0.3 up to about 1.0 DWPD for either three or five years. The P1 somewhat mitigates this by only offering large capacities of 500GB and up, so the total write endurance starts at a minimum of 100TB. This is adequate provided that most of the drive’s capacity is used for static data. If the P1 has to hold hundreds of GB of data that changes as frequently as a web browser’s cache and history, then 0.1 DWPD won’t be enough. But in a more normal scenario where most of the data is media like movies and video games, then there’s no problem.

The early projections for QLC NAND write endurance were in the ballpark of a few hundred program/erase cycles at most, which would have required the QLC SSDs to be treated very carefully. The QLC NAND that Micron is now producing in volume can last for a similar number of P/E cycles as early TLC NAND, which is how the Crucial P1 can be usable for general-purpose consumer storage duties. Even after accounting for the write amplification caused by SLC caching and a realistic proportion of writes being random, the P1 is still rated for the equivalent of 200 full drive writes on the host side. (If those drive writes were entirely large-block sequential writes such as from re-imaging an entire drive, then the P1 should last much longer, but Micron doesn’t want to complicate the endurance specs for their consumer drives that much. )

In spite of the tradeoffs of lower performance and endurance, QLC drives like the Crucial P1 are worth a look because of their potential to also have significantly lower prices. At around 22¢/GB currently, the P1 isn’t setting any records yet. Several industry reports have indicated that yields of Intel/Micron QLC are still poor, so the production costs of SSD-quality QLC aren’t meaningfully lower than TLC yet. The other major NAND manufacturers are being less aggressive about bringing QLC to market, but once they have introduced their competitors we will probably see QLC products offering a more significant discount over TLC. NAND prices in general are also in decline, with some higher-volume TLC products leading the way ahead of even the QLC drives.

The primary competition for the Crucial P1 is its close relative Intel 660p, as well as other entry-level NVMe SSDs. There is a low-end NVMe market segment with numerous options, but they are all struggling under the pressure from more competitively priced high-end NVMe SSDs. Products like the DRAMless Toshiba RC100 and HP EX900 haven’t been able to get any traction when the HP EX920 is hitting the same prices. Thus, it is also fair to compare the Crucial P1 against such faster NVMe drives. The P1 is a modest step up in price over mainstream SATA SSDs, so this review includes benchmark results from the Crucial MX500.

AnandTech 2018 Consumer SSD Testbed
CPU Intel Xeon E3 1240 v5
Motherboard ASRock Fatal1ty E3V5 Performance Gaming/OC
Chipset Intel C232
Memory 4x 8GB G.SKILL Ripjaws DDR4-2400 CL15
Graphics AMD Radeon HD 5450, 1920×[email protected]
Software Windows 10 x64, version 1709
Linux kernel version 4. 14, fio version 3.6
Spectre/Meltdown microcode and OS patches current as of May 2018
  • Thanks to Intel for the Xeon E3 1240 v5 CPU
  • Thanks to ASRock for the E3V5 Performance Gaming/OC
  • Thanks to G.SKILL for the Ripjaws DDR4-2400 RAM
  • Thanks to Corsair for the RM750 power supply, Carbide 200R case, and Hydro H60 CPU cooler
  • Thanks to Quarch for the XLC Programmable Power Module and accessories
  • Thanks to StarTech for providing a RK2236BKF 22U rack cabinet.

AnandTech Storage Bench — The Destroyer
IntroductionAnandTech Storage Bench — The DestroyerAnandTech Storage Bench — HeavyAnandTech Storage Bench — LightSYSmark 2018Random PerformanceSequential PerformanceMixed Read/Write PerformancePower ManagementConclusion



Crucial P1 review: A great value NVMe SSD

Super fast NVMe SSDs are still pretty pricey compared to your standard SATA drives, but thankfully there’s a growing number of budget NVMe SSDs that are starting to bring those lighting fast read and write speeds to the masses. I’ve already tested the excellent value for money WD Blue SN500 and Adata XPG SX6000 Pro, but now I’ve got the Crucial P1 in for testing, which is just a smidge cheaper than the SN500, and is also available in a handier 1TB size capacity. Does it have what it takes to make it onto our list of our favourites, though? Here’s wot I think.

Available in 500GB and the aforementioned 1TB sizes, the Crucial P1 is pretty much neck and neck with its WD and Adata rivals when it comes to overall price, as you can see from the table below (or at least it is in the UK). However, its superior random read and write speeds make it a much better choice for those after a larger, but still vaguely affordable NVMe drive for storing your games on.

SSD UK price (500GB): US price (500GB): UK price (1TB): US price (1TB):
Adata XPG SX6000 Pro £61 $78 £119 $150
Crucial P1 £64 $67 £99 $96
WD Blue SN500 £66 $65 N/A N/A

For me, random speeds are much more important than the sequential speeds you’ll see quoted on the box of an SSD, as they’re usually a much better indicator of how a drive will perform in day to day desktop tasks. After all, SSDs hardly ever read or write files in nice, neat adjacent blocks, which is what sequential speeds measure. Instead, they scatter bits of data ‘randomly’ all over the shop, which is why random speed tests are the key thing to pay attention to.

In AS SSD’s 1GB random 4K test, for example, which reads and writes 1GB’s worth of tiny 4K files all over an SSD’s storage banks, the 500GB model of the Crucial P1 I was sent for review managed a random read speed of 55.4MB/s, and a random write speed of 147.3MB/s. That’s a respective increase of 25% and 12% over the WD’s 44.5MB/s read and 131.3MB/s write speeds, putting it right up there with our best NVMe SSD champ, the Samsung 970 Evo (whose 500GB model still costs a whopping £95 / $90). That’s impressive for an NVMe SSD that’s practically a third less expensive than the gaming SSD top brass, and will no doubt feel just as nippy in day to day use as its more expensive rivals.

For gaming and daily desktop tasks, then, the Crucial P1 has its budget rivals beat. However, there are some a couple of downsides to the Crucial P1, especially if your PC regularly deals with large workloads when you’re not using it for playing games. When I ran it through CrystalDiskMark’s more intensive 1GB random 4K 8-thread-8-queue test, for example, the P1 only managed a read speed of 363.1MB/s, and a write speed of 911.4MB/s. And yes, I ran the test a second, and third, time, just to make sure it wasn’t a mistake, but alas, I got similar results every time.

The former is particularly poor, as the WD Blue SN500 managed just over 1000MB/s in both cases, while the SX6000 Pro came in with 1248MB/s read and 922MB/s write. Indeed, a 360MB/s random read speed is more what I’d expect from a traditional SATA drive in this kind of test (Crucial’s own MX500 SSD managed 398MB/s, in fact), so it’s likely to feel a lot less nippy if you’re often dealing with lots of files.

The Crucial P1’s transfer speeds left a lot to be desired as well. For example, when I ran AS SSD’s copy benchmark, which measures the transfer rate of three different file types (ISO, programs and games), the P1 only managed 779MB/s for the game part of the test, which is significantly slower than any other NVMe SSD I’ve ever tested. That’s still around twice as fast as a SATA drive, thankfully, but when you’ve got WD’s Blue SN500 managing 1454MB/s in the same test (and the SX6000 Pro around 1041MB/s), I suspect the P1 will once again start to feel a bit sluggish when you’re dealing with files that are a mix of large and small.

NVMe SSDs require an M.2 slot (above) on your motherboard

That puts the Crucial P1 in a rather tricky position. For everyday tasks, the £64 / $67 P1 is almost certainly the budget NVMe SSD to buy out of the WD Blue SN500 and Adata XPG SX6000 Pro, but if you’re going to be using it for transferring or moving big files around quite frequently, then you’re probably better off sticking with the 500GB WD Blue SN500.

For those after a cheap 1TB NVMe SSD, however, I reckon the £99 / $96 P1 still represents pretty good value for money, especially when the WD isn’t available in this size, and the Adata is so much more expensive. The P1 has its flaws, sure, but at this kind of price, it’s by far one of the cheapest ways to take advantage of what NVMe drives have to offer, and for the most part it’s still considerably faster than what you’d get on a standard SATA drive. Its endurance rating isn’t as high as other drives (coming in at just 100TB written for the 500GB model and 200TB written for the 1TB drive), but you still get a five year warranty with it, plus those excellent small file read and write speeds. The P1 may not be completely perfect, but at this price, it’s well worth considering for those on a budget.

Crucial P1 1TB SSD Review — Best Low Cost NVMe Drive?

By Nathan Kirsch •

Crucial P1 – Reviewing a Best Selling QLC SSD

The Crucial P1 1TB NVMe SSD was the number one selling drive during Amazon’s Prime Day sale this year as you could pick up the 1TB model for $79.99 shipped. The drive is now back up to $95.99 shipped, but we have a feeling that you’ll be able to find this drive at lower prices for Black Friday 2019. That is the time of year that gamers and enthusiasts usually look for rock bottom pricing to snag a good deal on an SSD. Black Friday has historically been a good time to lock in big savings and we think gamers are going to be looking for more storage space that will enable them to hold hot new game titles like Call of Duty: Modern Warfare and Red Dead Redemption 2.

At under $0.10 per GB the Crucial P1 1TB is an inexpensive entry-level M.2 NVMe drive capable of reaching sequential read/write speeds up to 2,000/1,700 MB/s. Those speeds blow a traditional hard drive away and will allow you to load games, open applications and boot your system faster than ever before. The smaller P1 500GB drive has peak sequential read/write speeds of up to 1,900/950 MB/s, which makes it a bit slower than its 1TB bretheren. The Random 4K read/write speeds are rated at up to 170,000/240,000 IOPS on the 1TB drive and 90,000/220,000 IOPS on the smaller 500GB model.

Crucial backs the P1 series with a solid 5-year warranty and an endurance rating of 100 Total Bytes Written (TBW) on the 500GB model and 200 TBW on the 1TB model. Over a course of five years that means you can be able to write about 54GB of data per day to the 500 GB drive and 109GB of data per day to the 1TB drive and still be covered under warranty. The life expectancy (MTTF) is set at 1.5 million hours. The Crucial P1 series does use Quad-Level Cell (QLC) NAND Flash memory, which was first introduced in 2018 with the promise of driving down SSD prices. Seeing how we are seeing 1TB drives available for under $80 shipped to your door here in 2019 it seems like QLC NAND Flash has fulfilled this promise. Sure, the write performance is lower than many TLC NAND Flash based products, but it seems to be good enough. Gamers usually store games for months or years, so the slower write speeds shouldn’t be bothersome. Besides most gamers in America have a 200 Mbps or 400 Mbps broadband internet connection, so they are only able to download games at these speeds. That converts over to about 25-50 MB/s write speeds to the SSD, a speed the Crucial P1’s dynamic write acceleration (SLC cache) can easily handle. The dynamic cache solution on the P1 series means an empty drive could be using over 100GB of SLC cache, but as the drive fills up with data the amount of SLC cache decreases. Once the cache if filled up by a long sustained write operation you’ll notice slower performance than the drives specifications as this model is speed rated with available SLC cache.

The drive that we are reviewing today is the Crucial P1 1TB model that is sold under part number CT1000P1SSD8. The Crucial P1 NVMe SSD uses the standard 2280 (80mm) ‘gum stick’ form factor with a single-sided design on both the 500GB and 1TB models. Crucial went with a black PCB for their entry-level drive, so it looks similar to all the other M.2 NVMe SSDs on the market today. Inside the box you’ll find the drive, but it is also worth highlighting the fact that with this drive you can download free Acronis True Image software from Crucial website which helps you to clone the data.

When it comes to the components used on the Crucial P1, Micron went with the Silicon Motion (SMI) SM2263ENG 4-channel NVMe controller, Micron 64-layer QLC NAND Flash chips, and Micron DDR3 DRAM for cache. All of the components are on the top of the SSD with no components residing on the back. It should also be noted that the Crucial P1 series has similar power loss functionality compared to the Crucial MX series of drives.

You also can download Crucials Storage Executive utility for free well from companys site. Storage Executive provides easy access to system information, drive health data, firmware updates and other drive maintenance options. When we installed and used Storage Executive on the Crucial P1 1TB review sample it alerted us to the fact that there was a new firmware revision available, so we updated our drive from firmware P3CR010 to P3CR013 before benchmarking the drive. The firmware update process was done on the drive on the Windows 10 desktop without issue and did not destroy any data on the P1.

Let’s take a quick look at the SSD test system and then move along and see how this 1TB drive performs against 10 other SSDs that are all 1TB or greater in capacity.

Crucial P1 review: Great-value SSD storage

Crucial has never made an NVMe SSD until now, despite a long and illustrious history with SATA drives. The simply named P1 isn’t just unusual for this reason, either: it’s also a rare instance of a consumer SSD using quad-level cell (QLC) NAND flash memory.

Just like how multi-layer cell (MLC) stores two bits of data per cell, and triple-level cell (TLC) holds three bits, QLC flash stores four bits per cell.

The main benefit of allowing for data to be stored so densely is that it allows for higher capacities without taking up as much physical space as MLC or TLC storage, although this isn’t particularly helpful on a standard 80mm M.2 drive; it’s more of a help to server rack owners. QLC is also the slowest, and has the worst endurance.

Crucial P1 review: Price and competition

Why, then, would Crucial choose QLC? For one thing, it’s cheap. Much like the firm’s BX500, the P1 is presented as a storage drive for those on tight budgets, and QLC memory helps keep the cost down. So far down, in fact, that this is the most affordable NVMe drive we’ve seen yet: the smallest 500GB model, which we’re testing here, works out at a mere 16p per gigabyte, while the 1TB model is just 15.5p.

Crucial P1 500 GB CT500P1SSD8 Internal Solid State Drive-up to 1900 MB/s (3D NAND, NVMe, PCIe, M.2), Black

£62.70 Buy now

Crucial P1 500GB 3D NAND NVMe PCIe Internal SSD, up to 2000MB/s — CT500P1SSD8

$57.99 Buy now

Even next to other value-oriented SSDs such as the Adata XPG SX6000 Pro, these are some very tempting prices, as the 512GB SX6000 Pro is 20.8p per gigabyte. The older yet higher-end Samsung 970, meanwhile, has only dropped to 21.7p.

Crucial P1 review: Performance speeds

The 1TB model looks an even better deal, as the 500GB model has surprisingly lower advertised sequential speeds: 1,900MB/s read and only 950MB/s write, the latter being remarkably low by NVMe standards. The 1TB version is said to have a 2,000MB/s read and a 1,700MB/s write speed. It’s common for larger capacities to be slightly faster, but seldom by this much.

Our testing with CrystalDiskMark showed the 500GB model’s numbers to be fairly accurate, as it scored 1,909.5MB/s in the standard sequential read test and 980.6MB/s in the sequential write test.

These results, true to the type of memory being used, are slower than those of the TLC-based SX6000 Pro, and much slower than those of the MLC-based 970 Evo. However, in the random 4K test, it was a far closer contest, with the P1 managing a respectable 337.5MB/s read speed and a 257.4MB/s write speed.

Image 4 of 7

The P1 was also more competitive in our file transfer tests, which – like the 4K random test – more accurately recreates real-use cases than sequential benchmarks. Not that it suddenly became blazingly fast, but the P1’s 999.7MB/s read speed and 998.6MB/s write speed in our huge files test are nipping on the SX6000 Pro’s heels.

It also kept up the pace in the tougher large files test. Here, Adata’s SSD dropped to 825.3MB/s read and 820MB/s write, but the P1 managed a very good 985.9MB/s read and 984.3MB/s write speed. That’s even getting close to the 970 Evo, which came in at 995.3MB/s read and 1,010.8MB/s write – not a lot of extra performance, for what is certainly a lot of extra cash.

Image 5 of 7

The P1 even took the lead in the small files write test, with 398.7MB/s, which is about 22MB/s faster than the SX6000 Pro and 35MB/s faster than the 970 Evo. Samsung’s SSD was back on top for read speeds, scoring 373MB/s, but that’s only a little better than the P1’s 364.2MB/s.

It’s not surprising that the P1 falls so far behind on sequential jobs, but we were deeply impressed by how well it kept up with costlier drives in our more realistic file transfer benchmarks. It also demonstrates how manufacturers’ listed speeds aren’t everything.

Crucial P1 500 GB CT500P1SSD8 Internal Solid State Drive-up to 1900 MB/s (3D NAND, NVMe, PCIe, M.

2), Black

£62.70 Buy now

Crucial P1 500GB 3D NAND NVMe PCIe Internal SSD, up to 2000MB/s — CT500P1SSD8

$57.99 Buy now

We won’t hazard a guess as to whether or not the 1TB model would be much faster in everyday use, but considering we’ve just seen a drive with a stated 950MB/s write speed overtake the 2,500MB/s 970 Evo in the small files test, you shouldn’t feel as though you’re getting a bad deal if you opt for the smaller model.

Crucial P1 review: Durability

QLC isn’t entirely vindicated, as the P1 does have lower durability than its rivals. The 500GB model is guaranteed for 100 terabytes written (TBW), one-third of the 512GB SX6000 Pro and 500GB 970 Evo, while the 1TB model is similarly modest at 200TBW.

That said, the only way you’ll break this before the five-year warranty runs out is if you’re writing several tens of gigabytes every single day, which seems unlikely in most cases.

Crucial P1 review: Verdict

Our only gripe with the Crucial P1 is that there isn’t a smaller, even cheaper capacity available; QLC lends itself better to larger drives, of course, but a 256GB or even 128GB version could have been irresistible to budget-conscious PC builders.

Nevertheless, the P1 represents outstanding value even at 500GB, and unless you’re in a line of work (or just have a hobby) that demands the very highest speeds at all times, it’s seriously worth a look.

Crucial P1 500 GB CT500P1SSD8 Internal Solid State Drive-up to 1900 MB/s (3D NAND, NVMe, PCIe, M.2), Black

£62.70 Buy now

Crucial P1 500GB 3D NAND NVMe PCIe Internal SSD, up to 2000MB/s — CT500P1SSD8

$57.99 Buy now

Key specifications
Capacity 500GB
Cost per gigabyte 16p
Interface NVMe
Claimed read 1,900MB/s
Claimed write 950MB/s
Warranty Five years RTB
Price £80

Nuclear power.

Volume 11, no. 4. — 1961 — Electronic Library «History of Rosatom»

Atomic energy. Volume 11, no. 4. — 1961 — Electronic Library «History of Rosatom»

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297Title pages





Emelyanov V. S.

Atomic science and technology and the building of communism 313

Fainberg Ya.B. counter-field traps 345

Vlasov N. A., Kalinin S. P.

Physical research of the cyclotron laboratory of the Institute of Atomic Energy named after I. V. Kurchatov 356

Marchuk G. I.

Review of methods for calculating nuclear reactors 370

A. I. Leipunsky, O. D. Kazachkovsky, M. S. Pinkhasik

The future of fast reactors 379

P. L. Gruzin

Some results and prospects for the use of isotopes and nuclear radiation in industry and scientific research in the USSR

395 Letters to the Editor


Guzhovsky B. Ya.

Elastic scattering of 15 MeV neutrons by copper, lead, and U nuclei 238 397

Yu. some isotopes 398

Sukhanov B. I., Rukavishnikov V. G.

Inelastic scattering of neutrons with an energy of 14 MeV on the nuclei of sodium, iron, nickel, lead 399

Komochkov M. M.

Attenuation of the neutron flux in the concrete shield of the synchrocyclotron 401

Vasiliev S. S., Mikhaleva T. N., Rudenko N. P., Sevastyanov A. I., Zazulin V. S.

Long-lived isotope Al 26 in structural aluminum of a nuclear reactor

404 Bibliography

404 Review of Gosatomizdat publications for 1961 and 1961 .

416 End page

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Brief Study Plan (Paper P1 & P2)

Management Accounting


  • 1 P1 — A. Cost accounting systems
  • 2 P1 — B. Forecasting and budgeting methods
  • 3 P1 — C. Project evaluation
  • 4 P1 — D. Accounting for uncertainty in the analysis
  • 5 P1 -1 E4 Short-term finance management

  • 6 P2 — A. Product pricing and decision making
  • 7 P2 — B. Competitiveness planning and cost analysis
  • 8 P2 — C. Budgeting and management control
  • 9 P2 – D. Monitoring and evaluation of the performance of responsibility centers
  • 10 CIMA exam preparation manuals in Russian

The purpose of writing the following article for me is primarily a preliminary dive into the content of the CIMA certification. In this article, I’m putting together a brief theory section of Paper P1 and P2. I will try to be informative and understandable enough to describe all the points mentioned.

  • marginal costing method of variable costs
  • variable direct cost method (throughput accounting)
  • absorption costing method
  • activity-based costing system
  • standard costing
  • back-flush accounting method
  • Total Quallity Management
  • Theory of Constraints
  • The role of forecasts and plans in resource allocation, performance evaluation and control.
  • Assignment of budgets and goals of the budgeting process, as well as possible conflicts (for example, between budgets for realistic planning and budgets based on hard-to-reach goals in terms of motivation).
  • Time series analysis, including moving totals and averages, seasonal adjustments, trend analysis using regression analysis, and application of the above methods in forecasting the volume of products and services.
  • Definition of fixed, variable, semi-variable costs; process-related costs; application of the above categories when forecasting financial results.
  • Budgeting Techniques: Limiting Factors, Constituent Budgets and Consolidated Budgets and Theirs.
  • Alternative approaches to budgeting, including incremental budgeting, scratch budgeting, and process budgeting.
  • Investment activity. Decision making, preparation of proposals.
  • Formation of the capital investment budget. Approval or blocking of individual projects. Checking completed projects.
  • Determination and calculation of cash flows for the project, taking into account inflation, taxes and cost at the end of the project.
  • Process costing to obtain cost estimates for strategic decision making.
  • Discount method.
  • Sensitivity analysis.
  • Project cost estimation methods: payback period PP, accounting rate of return ARR, net present value NPV or internal, rate of return IRR.
  • Non-financial factors influencing long-term decisions.
  • The use of annuities when comparing projects with different implementation periods and the profitability index in situations of capital rationing.
  • The nature of risk and uncertainty.
  • Sensitivity analysis for decision modeling.
  • «What if» analysis in software products.
  • Assigning probabilistic values ​​to key parameters within decision models.
  • Analysis of probabilistic models and interpretation of the distribution of project results.
  • The value of information and tables of expected values.
  • Multistage decision making. «Decision tree».
  • Relationship between cash, profit and balance sheet.
  • Credit cycle from the moment of receipt of the customer’s order to the moment of receipt of money and the payment cycle from the moment of approval of the order to the moment of payment.
  • Working capital ratios: receivables turnover, inventory turnover, accounts payable turnover, current ratio, quick ratio). The working capital cycle.
  • Characteristics of working capital across different types of business (eg, highly leveraged supermarkets), and the importance of industry benchmarking.
  • Cash flow forecasts, using spreadsheets as an aid to dealing with changing parameters (eg interest rates, inflation) and consolidating forecasts.
  • Parameters that are most easily changed, deferred or carried forward in forecasting.
  • Methods for assessing terms of payment and settlement discounts.
  • Preparation of an analysis of accounts payable and receivable by the timing of their occurrence and interpretation of its results.
  • Setting debt collection targets (eg motivational issues in credit control).
  • Comparative analysis of centralized and decentralized procurement activities.
  • Relationship between purchasing and inventory management.
  • The economic order quantity (EOQ) model and its critique.
  • Proper and improper use of trade creditors as a source of financing.
  • Types and characteristics of short-term financing: debt to suppliers and contractors, overdrafts, short-term loans and factoring.
  • Principles of short-term investment activity (eg maturity, return on investment, collateral, liquidity and diversification).
  • Types of investments (interest-bearing bank accounts, certificates of deposit, short-term treasury bills and securities).
  • The difference between the coupon rate of a debt instrument and the yield to maturity.
  • Export financing (eg documentary letters of credit, bills of exchange, export factoring, forfaiting).
  • Relevant cash flows and opportunities to use them in making operational decisions regarding the approval / rejection of contracts, pricing and cost-benefit comparisons.
  • The importance of strategic, intangible and non-financial judgments in decision making.
  • Consideration of relevant costs and revenues in decision making and their relationship to accounting concepts.
  • Margin coverage and full cost recovery as a basis for short and long term pricing decisions.
  • Simplified analysis of the assortment in the presence of restrictions in terms of demand for products / services and an additional production restriction.
  • Break-even analysis of the assortment range, including the construction of break-even and profit / volume charts, determination of the marginal profit ratio or profitability of sales, margin of safety (safety threshold).
  • Linear programming for more complex situations with multiple constraints. Solving problems with two variables using graphical methods along with an understanding of the principles of operation of simplex solutions, «shadow» prices, etc. (Note: there will be no questions requiring the full application of the simplex algorithm, at the same time, candidates should be able to form the initial matrix (simplex table), interpret the final simplex table and apply the information contained in the final table).
  • Sensitivity analysis of decision making models based on the cost-volume-profit ratio.
  • Pricing solutions for profit maximization in imperfectly competitive markets. (Note: tabular solution methods are allowed).
  • Pricing and financial implications of cream skimming strategies; establishing premium prices; market penetration strategies; strategies for selling at a loss (loss leader) — i.e. selling a certain product below cost; strategies for creating product bundles or offering complementary products and differentiating products that target different market segments.
  • Allocation of shared costs and decision making on the effectiveness of processes and products, taking into account relevant costs and revenues.
  • Cost analysis and use of the «quality function».
  • Benefits of Just-in-Time Production, Total Quality Management, Theory of Constraints, and the Application of These Methods in Decision Making in Modern Manufacturing Environments)
  • Kaizen costing, continuous improvement and quality cost reporting
  • Learning curves and how they can be used in the calculation of the forecast cost of products / services, including the calculation of the learning rate and the learning index.
  • Activity Based Management in overhead analysis and using this method to improve the efficiency of repetitive operations.
  • Target costing
  • Calculation of costs during the life cycle of a product and the importance of this method for developing marketing strategies.
  • Value chain and supply chain management, including the trend of outsourcing manufacturing operations to transition and developing countries.
  • Profit-sharing schemes in situations where, due to the size of the project, the limited number of contractors, or for security reasons (for example, in the defense industry), there is no normal competitive pressure.
  • Ability to use direct costing and process costing to allocate costs to specific cost objects, such as customers or distribution channels, and compare those costs with the corresponding revenue to determine multiple levels of margin, such as with a process hierarchy of costs.
  • Pareto analysis.
  • Control system concepts.
  • Using budgets in planning: rolling budgets for adaptive planning.
  • Accounting for responsibility centers and using budgets for control purposes: controllable costs and analysis of non-controllable costs; conceptual relationship between normative cost accounting and budget flexibility.
  • Evaluation of the consequences of achieving forecast results based on key financial indicators, including profitability, liquidity and asset turnover ratios.
  • What-if analysis based on alternating volume, price, and cost structure forecasts; use of spreadsheets to conduct such analyses.
  • Evaluate overall performance using variance analysis based on fixed and flexible budgets.
  • Behavioral aspects of budgeting: participation in budgeting and possible beneficial effects in terms of responsibility and motivation; possible adverse effects in terms of “budget overruns” and budget manipulation; setting budget targets for motivation purposes; consequences of approving cost standards, etc.
  • Non-financial performance indicators.
  • Criticism of the use of budgeting and recommendations from supporters of the balanced scorecard and «beyond budgeting» methods.
  • Organizational structure and its impact on accounting by responsibility centers.
  • Presenting financial information reflecting performance, highlighting controllable/non-controllable costs and variable/fixed costs, and attributing revenues and costs to specific cost objects.
  • Return on investment and disadvantages of this indicator; indicators of residual income (residual income) and economic value added (EVA).
  • Behavioral consequences of control and performance management.
  • Transfer pricing theory, including perfect and imperfect market or no market for intermediate goods.
  • Use of transfer prices based on agreements, market value, variable costs, cost + method. «Double» transfer prices and lump-sum payments as a way to solve some issues.
  • Relationship between transfer pricing and tax liabilities in international transactions, implications for currency regulation, and possible misrepresentation of intra-group transactions in order to comply with tax laws.
Google Disk content
P1. Collection of training and test tasks
P1. Operations performance management. Section A-B
P1. Operations performance management. Section C-E
P2. Collection of training and test tasks
P2. Business performance management. Section A-B
P2. Business performance management. Section C-D
P2. Flash cards

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Ivan Shamaev

Dark Alliance — DTF games

When Marvel Avengers is not the worst co-op game yet.


Action games in the Dungeons and Dragons universe are nowhere near as well known as their RPG brethren. But there were still interesting experiments, take at least the Baldur’s Gate: Dark Alliance dilogy. Although it would seem that the setting makes it possible to make some interesting slasher in the style of the Darksiders trilogy. And to the delight of fans of Wizards of the Coast in 2019Dungeons and Dragons: Dark Alliance, a cooperative action game for four people, was presented at TGA. At that time, the trailer itself excited the public, no one was against Rubilov in the scenery of D&D with eminent heroes in the lead roles. True, after some time, the developers showed the first gameplay of their project, and even then doubts began to creep in among the people, but they still believed that the game would turn out to be a worthy successor. And at the exit, the players realized that it was still worth listening to doubts. But first things first.

Not much to say about the plot. A mysterious shard has been discovered in the world, which has great power, and several factions decide to take possession of it. He is attacked by many, from ordinary goblins to powerful necromancers. And our quartet, consisting of the dark elf Drizzt, the dwarf Bruenor, the archer Catti-brie, and the barbarian Wulfgar, will have to place them. And despite the eminent cast, for fans of the original role-playing game, the characters feel more like just skins that are needed only for external differences. They practically do not contact each other, at most they will say something at the beginning of the mission. Sometimes there is a feeling that if you replace them with random heroes, then the difference would not be great. For people who have not read the original books about this company, the characters will remain empty blanks that will not say anything interesting.

But in such projects, you can close your eyes to the lack of an interesting plot and unrevealed characters if the gameplay itself is good. But here, too, Dark Alliance has problems.

The gameplay cycle is as follows: you come to the location, go from point A to point B, in the finale, kill the boss. Sometimes missions are diluted with activities like “destroy 5 ballistas” and searching for secret chests, but this does not increase replay value much. And one could turn a blind eye to this monotony if the combat system itself was exciting, like Vermintide 2, for example, but there are problems here too.

The combat system itself may be of interest at first, especially when you look at the local leveling with the number of unlockable moves. But in the end, you still have to use the most basic techniques. new combos are not effective. they work every other time, and they themselves often lose in effectiveness to basic attacks. Active skills are trying to diversify combat, but they do not help much and in 90% of cases all battles come down to the same type of calling enemies.

In addition, the strikes themselves have no impact. Sometimes enemies can still stun once or twice, but mostly they will stand defiantly and continue to hit you. I don’t think it’s necessary to say how important such a thing is in slashers.

Everything about this clip is great.

In addition, the enemy AI is terrible. Enemies often, when they notice players, at first they don’t understand what’s going on for 5 seconds and only then they start to fight. Or another example, the enemies do not have the ability to jump and climb on a hill. And such a trifle completely kills the whole balance. After all, why fight with the enemy in an open battle, if you can take a “hard-to-reach” place and shoot enemies from there for an archer. Well, sometimes they like to change their aggro every 2 seconds and end up doing nothing.

Miracles of AI.

Well, the overall monotony of opponents is not for the better. At first, the bestiary seems impressive, but over time, you realize that apart from a couple of enemies (for example, trolls), the opponents are the same in terms of tactics and techniques. Even sometimes interesting bosses don’t help much.

Despite the crooked combat system, the game tries to extend its life cycle with the help of the loot system, but there are problems with it. It is made in the “best” traditions of Anthem. You won’t be told what specific item you’ve picked up until you’ve completed the level. The maximum will indicate the type of armor and its rarity. And it’s not a fact that your new ax will be better than the previous one.

As a result, due to all these problems, the gameplay cycle discourages the desire to continue playing the game after a couple of missions. It becomes not interesting to play after a few levels. Dark Alliance has nothing to captivate and interest the player. The co-op will allow you to stay in the game longer, but this is more the magic of the genre, and not the dignity of the game.

But there is still some good stuff in Dark Alliance. The design of locations from a visual point of view turned out to be excellent and diverse. Players will descend into ice caves, then into a city in the middle of a mountain, then into a troll camp in the midst of drunkenness, and so on.

The mechanics with the camps turned out to be just as interesting. After some skirmishes, players will have the opportunity to create a camp and make a choice: rest in it and fully recover, or immediately go on without being distracted by a break, but increase the chances of getting better loot. And in the end, this gives rise to interesting situations from the category of “maybe it’s still worth the risk and try your luck, or is it better to play it safe?”.

Dungeons and Dragons: Dark Alliance had a chance to become at least a good co-op slasher that could captivate for another month, but due to the broken combat system and the general curvature of the project, the game feels more like an alpha than a full-fledged release. Most likely the game will suffer the same fate as Anthem or Avengers. True, if the latter are at least somehow remembered, then the new D&D will disappear from the head pretty soon.

HTC Desire Z review, part 1

To be honest, I’m not a big fan of Android. And not because “Android outsells the iPhone, and now the iPhone shines as a marginal niche player, as it once did with the Mac, and all Apple fans are upset by this fact,” as some critics who have to face on expanses of the Internet. As I once wrote, it’s not about market share, and I’m sure that Apple never had the goal of completely controlling the smartphone-mobile market, it’s enough just to make all the money on it. Here Nokia dominated it, and what did it give her? 🙂

And even from a business point of view, there is no reason to worry, since about a third of the custom projects that we have now are orders “for Android”. The audience there is still different, not as “high-quality”, as in the case of iDevices, but it is already quite large to start paying attention to it. Actually, in connection with my work, various devices on the Android system periodically fall into my hands, and my last catch is the HTC Desire Z, which will soon go on sale in Russia. I honestly used this device for the last two weeks as my main device (phone-mail-calendar-twitter-etc), and I’m ready to share my impressions about it.

The review will traditionally be divided into two parts — the first is devoted to the hardware of the device, the second — to the software shell. But even in the hardware you will not find detailed numbers, rigorous comparison of characteristics and other things — I prefer subjective reviews, and I write my real reviews, what I really think, and not what the manufacturer might like to see / distributor/marketer. Moreover, in the review you will not find a lot of photos of the device, because I don’t know how to take pictures, and I also don’t want to spread anything. But the detailed characteristics of the device can be viewed on the manufacturer’s website here, in the same place, by the way, you can find many pictures of the device itself. I will refer to numbers or show photos if necessary for the review itself (if you need a lot of photos in a review, you can go to, I just got tired of scrolling through their last Nokia N8 review, there were so many photos).

HTC Desire Z vs iPhone 3GS, taken by HTC Hero
Let’s start with the physical dimensions. The Desire Z is quite similar in size to the iPhone (I have a 3GS), only the height of the Desire Z is 1-2mm longer than the iPhone, the width is 1mm narrower than the iPhone, and the thickness of the Desire Z is about 2mm thicker. Such a “bulky” Desire Z is understandable, since the form factor of the device is, in addition to the touch screen, the gadget from HTC also has a hardware QWERTY keyboard. It all looks something like this:0049
Desire Z opened, taken by iPhone 3GS
As for the case, I liked this part of the phone, although I found the phone a little bulky, thick and heavy. The gray plastic of the case is pleasant to the touch, and behind it is “diluted” with a steel cover that closes the battery compartment. This lid opens with a special button on the case, and I had an idea that it could be inadvertently hooked when pulling the phone out of my pocket, but this did not happen. (And the lid, by the way, got a little scratched in two weeks from carrying it in your pocket — usually there is another phone and car keys. So in long-term use, be prepared for this wear). In any case, the ability to replace the battery will probably be appreciated by those who are worried that the battery in the iPhone cannot be replaced “on the go”. The button to turn off and turn on the screen (it is also the on-off button of the phone) was moved to the top, like on the iPhone, where it is adjacent to the 3.5mm headphone jack. On the right side of the screen there is a button for controlling the camera, which is convenient when you take pictures with one hand and do not need to tap the screen in order for the camera to take a picture. There is also a small hole at the top of the back panel, which I suspect is a second noise-canceling microphone.
On the left side of the screen (in the upper half of the device) are the volume up and down buttons (same as the iPhone), but below is the Micro-USB connector. (At this point, a moment of hatred for all phone manufacturers who still can’t agree on a single connector for phones, as a result using either mini-USB, then micro-USB, or something else. As a result, if I go somewhere then with HTC Hero and Desire Z, I need to bring two different USB cables with me). On the front of the phone, below the screen, there are 4 touch buttons that all Android devices have — Home, Menu, Back and Search (in that order). However, when switching between Hero and Desire Z, I found myself constantly poking at different buttons, because in Hero, for example, the buttons go in this order: Answer a call / Home / Menu / End a call (also a button phone on/off). And in the second row, the search and back buttons were also separately located, and such a discrepancy in the location of the buttons was confusing. I hope that the manufacturer somehow standardizes the placement of buttons between devices and will not confuse users.
In addition to the buttons, on the front panel of the phone, under the screen, there is also a touchpad — a small square-button that helps you move between objects. I used it only once — to check if it works and how it works. Well, in addition, the phone has 43 more buttons of a sliding QWERTY keyboard with all sorts of auxiliary buttons (the Russian keyboard, however, is YTSUKEN, but not quite, some letters on the keyboard were located unusually (for example, the letter zh). Perhaps someone really loves hardware keyboard (I tried it, cool, but nothing more), but I noticed that I typed much more texts using the virtual keyboard on the screen, especially since the hardware keyboard only works in portrait mode (which is natural), but I had the feeling that most objects on the screen in Android in this mode are not drawn as efficiently as in vertical mode.In addition, I still did not understand how to type punctuation marks on the hardware keyboard in the Russian layout — I pressed all sorts of FN and Shift, but nothing happened, so I switched to English and typed them in. In general, communication with the hardware keyboard left some residue, although I suspect , if you purposefully try to master it, then you can probably type texts there, perhaps even better than on a virtual one.
Concluding about the case, I want to say that I liked the implementation of the keyboard “sliding out”, when the phone, as it were, “splits” into two parts, which are connected only by a cable and two levers — while the phone “pops” juicy when opened. True, I’m not sure how long such a design will last — after two weeks of testing, this mechanism began to work a little more freely than at the beginning. I have not tested for fragility, but I suspect that in the crazy hands of a 3-4 year old child, this mechanism can “break apart” into its components very easily.
The Desire Z screen is even slightly larger than the iPhone — its diagonal is 3.7″, resolution is 480×800. This, of course, is better than that of my 3GS (there is 320×480), 3.5″ diagonal, but it falls short of the iPhone 4 screen with its 640×960. From the point of view of the overall quality of the screen, there are no particular complaints here — high-quality viewing angles, rather “juicy” color reproduction of images, a bright picture even outdoors on a sunny day. This device uses a Super LCD panel from Sony, which HTC switched to after Samsung said that they themselves lacked SuperAMOLED screens for their phones. From what I read about comparisons of S-LCD and SuperAMOLED, they do not differ much in terms of image transmission (although SuperAMOLED has a higher contrast picture), so HTC lost a little. The texts on the screen read perfectly, I would even say — almost like on the iPhone 4, so, despite the fact that this is not a Retina display, everything is not so bad.
I can’t say that the battery was amazing, but in general, when used in an average degree of activity (a couple of dozen calls and messages a day, twitter updates, browsing traffic jams, mail and any other nonsense), the phone lasted about a day and a half . And this annoyed me the most, because this half of the second day turned out somehow not there, and not here — anyway, at the end of the first day I had to charge, and if I didn’t charge it, because “so I still have half the battery!”, you’ll regret it the next day.
By the way, after the iPhone, phones that require you to “turn off” to replace the SIM card are puzzling — yes, I do not like the SIM card substrate that the iPhone uses, because you need to carry a special thing with you in order to remove it , but the phone does not need to be turned off and on. And for HTC, Hero, Desire Z, in order to change the SIM-card or memory-card, you have to remove the battery. By the way, there is a funny story about the SIM and memory card when I tried to plug a Micro-SIM cut for iPhone into Desire Z. After removing the battery, I saw a tray similar to the one in the Hero for the SIM card, only smaller , and I immediately “realized” that this is probably progress striding around the planet and HTC also began to use Micro-SIM, like in the iPhone 4/iPad. I began to put the cropped Megaphone card in there, and, imagine, “ALmost got in!”. Wow, I thought, probably, if you file it a little with a file, I thought, it will go in there wonderfully, and happily took out a knife to “chop” the SIM card a little more. But it still didn’t come in, and by the time I realized that my “sawing” was about to significantly reduce the size of the SIM card, I finally looked at the picture and the text near the connector, and then it dawned on me that I was trying to plug SIM card into the memory card slot. So it is still useful to read, do not forget about it.
And finally, about the camera of the device. It is stated that the camera takes photos with a resolution of 5MP, there is autofocus and a flash. In principle, the photos turn out to be quite good, considering that both of these shots were taken in conditions of not very good lighting: leaves the feeling that the 5MP on the iPhone 4 takes photos significantly better than the 5MP on the Desire Z. Moreover, in my layman’s opinion, even the Nokia N8 with its hundred thousand million megapixels (more precisely, 12MP) takes worse photos than the iPhone 4 — there photos , as it seems to me, they turn out better, although, perhaps, one of the professional photographers may dispute this. But now I specifically reviewed the photos that I took on the iPhone 4 when I had it, and they lack some kind of “blurring”, which, it seems to me, is very often present in photos from Android phones.
Moreover, this camera is claimed to be able to shoot video in high resolution 720p, however, this mode is disabled by default, and I think I even know why. Even in the normal mode of 800×480 pixels, the video slows down noticeably from time to time, and when I set the 720p option for shooting, every 4-5 seconds the video shooting was interrupted by significant pauses for 2-3 seconds. It seems that the phone’s processor (800MHz) can’t cope with video encoding (it is saved in 3gp format), but the iPhone 4 had no problems with shooting video of this resolution. A faster processor (1GHz) and hardware support for the H.264 format, in which the “apple gadget” shoots, also helps here. Therefore, if for some reason you have video in this resolution on your phone, do not rely on HTC marketing statements, they can play a bad joke on you.
In summary, I want to say that I liked the device from a hardware point of view — a good screen, a high-quality case. There is a feeling of a premium device, although perhaps HTC will not position it as such, so as not to compete with the future flagship of the Desire HD line (or whatever it is). I’m not a fan of a hardware keyboard, so the fact that it makes the phone thicker makes me a little frustrated, plus I’m not sure about the durability of this design. And I would remove the touchpad from the front panel, but since HTC puts it there, someone probably needs it. And the rest — a very nice device, if not for Android :). But more on that next time.

Crucial X8 Review: The Best 1TB Portable SSD

The continuous evolution and performance of SSDs has also revolutionized the external drive sector. Nowadays, it is no longer necessary to buy external hard drives to have plenty of free space, it is more convenient to rely on very high performance external SSDs such as the 1TB Crucial X8.

Crucial X8 is a portable NVMe SSD with USB-C 3.2 Gen 2. Data in seconds. Let’s find out all the details about one of the best external SSDs in the Crucial X8 review.


The small box contains a limited amount of contents: SSD, USB to USB type C cable and a small instruction manual.

Design, construction and specifications

Crucial has created a high quality external drive that combines anodized aluminum and soft plastic edges. The one-piece body of the case is almost entirely made of aluminum, thanks to this material, you can better protect the drive from any impacts and provide more efficient heat dissipation. The body is not IPxx certified, but has been tested to withstand 2m drops and shock, vibration and extreme temperatures. The design excellence allows us to take an external drive with us without worrying too much about possible damage during transit, and removes the burden of worrying about the integrity of our valuable data.

The design of the product is minimal and modern, characterized by simple lines, clean surfaces and soft corners. There is only a shiny metal strip with the manufacturer’s logo on the case, there are no working LEDs that could come in handy. Exceptionally compact dimensions, we are talking about only 11 x 1. 1 x 5.3 cm and weighing less than 100 grams, which makes the product not very easy to carry, but even pocketable.

Inside the aluminum case is a Crucial P1 NVMe SSD with NAND QLC. This type of memory provides high performance and durability that were unthinkable just a couple of years ago. The Crucial X8 is available in two different storage sizes: 500GB and 1TB. In the 1TB version, the actual available space is 930 GB.

Usage and performance

Crucial stated that the maximum sequential read speed for the X8 is 1050MB/s. This is a very high value, confirmed by tests conducted with CrystalDiskMark, during which we reached a value of 1025 MB / s. The data on the maximum sequential write speed, which is about 850 MB / s, is also impressive.

Test data confirms the quality of the product and absolutely convincing performance in terms of reading and writing to disk. However, to achieve this level of performance, it is not enough to plug the drive into a simple USB port, you need to have a PC/Mac behind it that can fully support you during the read and write phases.

Generally, Crucial X8, connected to a good PC, can guarantee excellent performance in any case, both in the read and write phase, and allow you to always carry a large amount of data with you and, above all, to transfer them in a short time.

Connected via USB Type C 3.2 Gen 2: The highest standards in read and write speed. However, this type of connection may be limited by your current hardware, classic USB 3.0 reaches 400-450MB/s read and write, but this design choice will allow you to use the drive for years and always have optimal performance. even on your next PC and Mac.


The Crucial X8 is available in two different sizes of memory, 500 GB and 1 TB, which sell for 130 and 155 euros respectively. The price is certainly not the cheapest, but it is certainly in line with what offers a product of much higher quality than the average and with excellent features to say the least. Given the difference in price, we recommend purchasing the 1TB version.


The Crucial X8 1TB is the perfect external drive and one of the best external SSDs on the market: easy to carry, beautiful, reliable, with plenty of space available for our data, and capable of high read and write performance. The internal NVMe drive and USB Type C 3.2 Gen 2 connectivity guarantee top performance that allows us to move large amounts of data in a short amount of time, provided you have the right hardware.

The ultimate solution

Design, construction and specifications

Our opinion

The Crucial X8 1TB is the perfect external drive and one of the best external SSDs on the market: easy to carry, beautiful, durable, with plenty of space available for our data, and capable of high read and write performance. The internal NVMe drive and USB Type C 3.2 Gen 2 connectivity guarantee top performance that allows us to move large amounts of data in a short amount of time, provided you have the right hardware.

Meta-analysis and determination of the critical validity of scientific publications

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TEMA: meta-analysis and determination of the critical validity of scientific publications TUDOR GREJDIANU- dr.hab.în med., profesor universitar

2. Meta-analysis

Relevance of meta-analysis
Types of literature review
Types of medical databases
What is a meta-analysis?
Purpose of a meta-analysis
Objectives of a meta-analysis
Steps of a meta-analysis
Determining the criticality of medical science
10. Conclusions.

journals with more than 2 million
articles annually) make it impossible
to retain medical knowledge

4. Relevance of the meta-analysis justified:

• Reviews have always been part of the
medical literature.
• They were carried out by well-known
leaders in their respective fields, who
searched for and collected
existing knowledge regarding the conduct of an effective
ad hoc method — meta-analysis.

5. Types of literature reviews

• Narrative
• Systematic
• Meta-analysis


0049 category.

• Most narrative
reviews are non-systematic
because the author did not report all evidence
from the

7. Advantage of descriptive reviews

• They are much easier to implement
• No special
fixing standards need to be followed.
• Can be sold in full
by one person.
• Very useful when the subject matter is
slightly known.
• Reflect views in general terms on
brochures of special topics.

8. Systematic reviews

• A special type of scientific research,
carried out according to a specially developed methodology
, the object of which is
the results of
• The aim of the
systematic review is to provide a measured and unbiased
study of the results of
previous studies.

9. Benefit of a systematic review

• Reduces bias in published
study results
• Summarize the evidence for published
study results.
• Reduces the time interval from the start of a
study to implementation of the results.
• Improved accuracy of results.
• Identify differences between
research studies.

10. Types of information resources

• primary information resources.
• secondary information resources.

11. Types of information resources

Primary information resources
• These are information resources in which
published original scientific research
Secondary Information Resources
• These are information resources that
relate to original scientific research or that offer
bibliographic information about views
on original scientific publications.

12. Primary information resources

Medical journals
Research registers
Published papers
Conference papers.
Non-bibliographic databases

13. Secondary information resources

• Repeated journals
• Bibliographic databases
• Non-bibliographic databases
• Library catalogues.

14. Internet

• Provides the opportunity to obtain
primary information resources, as well as
secondary information resources.

15. Types of medical databases(1)

General medical databases
Databases by disciplines.
Databases with an economic aspect
Databases for the synthesis of literary publications

16. Types of medical databases (2)

• Gray literature databases
• Practice guide databases
• Health policy and management databases
• Document databases of
medical conferences.
• Databases of reports at various

17. Information obtained from scientific publications?

Publication date
Publication type
Research measurement tools.
Patient diagnosis.
Place of treatment.
Duration of treatment.
Treatment type.
Effect value
Value threshold.

18. Meta-analysis

• Quite often, the results of studies
evaluating the effectiveness of the same
treatment or prophylactic intervention or diagnostic method for
the same disease differ.
• In this regard, there is a need
for a relative evaluation of the results of
different studies and integration of their results in order to
obtain a generalizing conclusion.
• One of the most popular and rapidly developing system integration techniques
today is the meta-analysis technique.

19. Meta-analysis

• International Epidemiological Association
«combining the results of various studies,
… consisting of a qualitative component
• For example,
the use of
such predetermined
criteria for inclusion in the analysis, such as
completeness of data, the absence of obvious shortcomings in
the organization of the study, etc. ) and
• quantitative component

processing of available data).»

20. What is a meta-analysis?

• Meta (DEX) = composition element that makes sense
«After», which means «transformation» or «change».
Meta-analysis is one of the terms of evidence-based medicine.
• Differs from a systematic medical literature review
in that meta-analysis is a methodology
for combining dissimilar and
studies by different authors on the same topic to increase the reliability of
estimates of similar results
• The term «meta-analysis» was introduced into scientific language at 1976
, scientist Gene Glass.

21. Meta-analysis

• The purpose of a meta-analysis is to identify
the study and explanation of differences
(due to the presence of statistical heterogeneity
or heterogeneity) in
study results.

22. Definition of meta-analysis

• 1976 (J. Glass) – «analyzes-analyzes» is a
systematic analysis of some
results of individual scientific publications
with the aim of combining them.
• 1997 (Greenhald) is a systematic
analysis of the numerical results of
clinical scientific publications that studied the same problem

23. Meta-Analysis Driven Concept

Meta-Analysis Driven Concept
• Meta-analysis helps determine:
The intensity of the relationship
between X and Y effect sizes.
Accuracy of the effect size of the entire population
(definition of confidence interval
— threshold value).

24. Tasks of meta-analysis?

Meta-analysis has two main objectives:
• Comparison — the results of two or more
scientific publications to determine
there are differences in values ​​between them.
• Combined — the results of two or
more scientific publications to determine:
— Mean effect size
— Global threshold of significance.

25. Meta-analysis steps


26. Identification

• The first step of the meta-analysis is
identification of all articles
corresponding to the studied problem
topics. Main sources of information
for meta-analysis:
• COEHRAINE library Register of RCT;
• CANCERLit, AIDSLine, ToxLine;
• Index Medicus;

27. medline

• The most comprehensive medical database
(10 million reviews and documents) – “something for
• The oldest medical database
«familiar to the vast majority of physicians».
• Valid, free of charge through
most sources
— National Library of Medicine
— BiomedNet. etc.
• Difficult to use and requires a lot of «effort»
to determine the importance of the information found.
• Used when evidence is missing.

28. 2. Sampling

• If the author has collected a lot of scientific information,
he will have to make a correct sample.
• To do this, he must determine:
— Scientific research has sufficient
information for analysis.
— Study design.
— Year of the study (modification of
technology, dosing of medicines).
— The dose of drugs used in the
scientific study (to ensure that an effective
treatment dose is administered).
— Language of the article — You and your colleagues must be
able to read it.
— Age of the patient (adult population or after 60
— Location of the study (ambulance,
outpatient, inpatient).

29. 3. Retrieval of

• If
relevant groups of scientific publications have already been identified, in the next step the author of
must extract information from each
• There are many sources of errors.
— Article may be spelled incorrectly due to typographical errors.
— Tables are interpreted incorrectly.
— Errors can be at the beginning or throughout the

30. Properly conducted meta-analysis makes it possible to reduce errors:

A well-conducted meta-analysis makes it possible
to reduce errors:
• Two reviewers participate individually
in the meta-analysis.
• Possibly 3 reviewers to organize
or discuss unclear questions in the
• Preparing reviewers for the processing of
large research papers.
• Comparison of the result with the content of articles
of a scientific publication.
• Use of standard databases.

31. 4. Analysis

• There are many irregularities in the analysis process
meta-analysis data. First
it is necessary to define some key terms
• Uniformity and homogeneity describe the degree of
comparison between research groups.
• Correctly combine scientific
studies from peer groups.

32. Definition (significance) in conducting a meta-analysis

There are three steps to
defining a meta-analysis:
0049 that they are reliable?
2. There are important results for my
3. There are reliable results.

33. Definition of reliability in a meta-analysis

1. Correct wording of clinical questions
2. Adequacy of criteria introduced for
selection of scientific articles.
3. Were some significant
studies found?
4. Recognition of the authenticity of
scientific publications submitted.
5. Reproducibility of scientific studies.
6. Uniformity of study results.

34. Usability of medical information

• Formulas of usefulness of medical information
• Usability = significance x confidence
Significance : measures the frequency with which we encounter
daily with evidence or type corresponding to
• Reliability : a measurement that describes
the corresponding true information.
• Effort = amount of time, cost of access,
need for adaptation.
• Comprehensive communication and communication with authors.
cu tratament
Total subiecţii în grupul cu tratament
P1 = a : n1
Nr. De subiecţii cu rezultate în grupul
fără tratament
Total subiecţii în grupul cu tratament
P0 = b : n0


χ2 =
n1 * n0 * m1 * m0
H0 – ipoteza nulă
χ2calculat > χ2tabelar – răspingem H0
χ2calculat < χ2tabelar – acceptăm H0

38. Critical definition of medical literature0575 • Why is this article published?

• What is the important question that the
research study answers?
• What type of study was done?
• Has an adequate methodology been chosen?
• Population in which the
study was conducted?
• What are the results of the study?
• Reliability of study results.
• Are the results of practical use?

39. Meta-analysis

• Meta-analysis – comparative new method of generalization 9
quantitative data from homogeneous studies to obtain summary statistical indicators
• Meta-analysis — it is advisable to use
when conducting a systematic review of the literature for an integral assessment of the effectiveness of
one or another method of treatment, prevention and diagnosis, and
also to obtain summary indicators of morbidity
, mortality and risk factors
for the development of a particular disease.