Quality Standards
New EFLM goals for Coagulation: An example analysis of an Atellica 360
We look at the impact of new EFLM goals for coagulation assays on the assessment of an Atellica COAG 360.
Atellica 360, an example analysis of coagulation assays using new EFLM goals
March 2023
Sten Westgard, MS
EFLM has added new goals for coagulation. How do instruments stack up when measured against these new standards?
The Atellica 360 data comes from the Institute for Clinical Chemistry and Pathobiochemistry in the Department for Diagnostic LAboratory Medicine at the University Hospital in Tubingen, Germany:
Evaluation of the Atellica COAG 360 coagulation analyzer in a central laboratory of a maximum care hospital, Horber S, Lehmann R, Peter A. Int J Lab Hematology 2020;42:28-36.
This study covers routine coagulation parameters, Factors 2, 5, 7, 8, 9, 10, 11, 12, as well as APTT and PT INR ratios and several more. Only these parameters listed will be analyzed here.
"Commercially available control samples... in the normal and abnormal range or respective parameters were used to determination of intra- and inter-assay precision and accuracy. Intra-assay precision was calculated for all indicated parameters by repeated measurements of the repsective control samples 10 times in a single batch....Inter-assay precision was determined by measuring control samples twice a day over 20 days....Intra-assay accuracy was calculated as mean percentage between measurement results and known target values of commercially available control samples."
The intra-assy precision and accuracy are the numbers we will use for our analysis. The TEa goals applied can be found on our Consolidated Hematology and Coagulation Performance Specifications page.
| Atellica COAG 360 2020 EFLM minimum | ||
| TEST | % Bias | %CV |
| APTT 1 | 0.40 | 1.40 |
| APTT 2 | 2.70 | 1.50 |
| PT INR 1 | 3.80 | 1.70 |
| PT INR 2 | 1.6 | 2.50 |
| FII F2 1 | 2.4 | 1.60 |
| FII F2 2 | 1.8 | 1.50 |
| FV F5 1 | 4.3 | 4.80 |
| FV F5 2 | 0.2 | 7.90 |
| FVII F7 | 7.3 | 4.00 |
| FVII F7 | 3.9 | 3.20 |
| FVIII | 0.9 | 1.90 |
| FVIII | 5.5 | 4.80 |
| FIX F9 | 1.1 | 4.80 |
| FIX F9 | 5.3 | 4.10 |
| FX F10 | 8.7 | 5.40 |
| FX F10 | 8.0 | 5.40 |
| FXI F11 | 3.3 | 4.20 |
| FXI F11 | 4.4 | 3.3 |
| FXII F12 | 3.1 | 1.6 |
| FXII F12 | 1.6 | 2.6 |
Sigma-metrics according to EFLM-derived DESIRABLE performance specifications
For most tests, the EFLM desirable specifications used to be the de facto global standard, but fell out of favor due to their toughness. As this graph shows, the desirable goals make the Atellica COAG 360 look pretty bad. 90% of the performance falls below 3 sigma.
Not surprising then, that EFLM recommended lowering the standards.
Sigma-metrics according to EuBIVAS-derived MINIMUM performance specifications
There is improvement, but there is still a majority of performance below 3 Sigma. Only one data point gets in the bull's-eye..
Conclusion
Even with possibly the most favorable assessment (using minimum specifications), the Atellica COAG 360 doesn't make a passing grade according to the EFLM goals. As we continue to analyze more assays and platforms for coagulation anlayzer, we'll find out if the Atellica is just one of many instruments that can't hit EFLM targets, or if it is the outlier.