Quality Requirements
A selection of SEKK-DMax specifications
The Czech EQA program SEKK has one of the largest lists of analytical quality performance specifications. They are modeled after what's called the Dmax. How does this specification compare to TEa? Let's see.
A Selection of SEKK Dmax (2015) analytical performance specifications
SEKK is the Czech Republic EQA programme
These performance specifications listed below are created for a unique specification called Dmax.
Dmax is "the long-term reproducibility multiplied by 2.5, where 'long-term reproducibility' means: (2 years) in CV% either [1] average CV of all results of all EQA rounds from last 2 years for those analytes where we use only one assigned value (that is - all resuls are compared to one assigned value) or [2] average CV of peer groups with N> 10 participants for those analytes where the results of participants are normally evaluated within homogenous groups (that is - each group has individual assigned values)."
"The size of Dmax we verify by the calculation based on intra-and inter-individual biological variability (database c. Ricos) and we aim not to set the value of the Dmax more stringent than that obtained by calculation from biologic variability (with some exception, e.g. CRP)."
In other words, Dmax is more reflective of "state of the art" since it is built on estimates of actual historical performance of test methods, and the goal is not to develop specifications more stringent than what biologic goals would dictate.
Below is a selection of the SEKK Dmax. A full list would cover hundreds more analytes in additional scenarios, including CSF, POC, etc.
| Sample type |
Analyte |
Dmax | CLIA | 2014 Ricos Desirable TEa |
| Serum | Amylase | 15 | 30 | 14.6 |
| Serum | α-fetoprotein (AFP) | 20 | ± 3 SD | 21.9 |
| Serum | Alkaline phosphatase (ALP) | 24 | 30 | 12.04 |
| Serum | Albumin | 12 | 10 | 4.07 |
| Urine | Albumin | up to 30 mg/dL: 30% above 30 mg/dL: 21% |
46.1 | |
| Serum | Alanine aminotransferase (ALT) | 15 | 20 | 27.48 |
| Serum | Aspartate aminotransferase (AST) | 15 | 20 | 16.69 |
| Serum | Bilirubin (total) | 21 | ± 0.4 mg/dL or ± 20% (greater) | 26.94 |
| Serum | Calcium | 10 | ± 1.0 mg/dL | 2.55 |
| Urine | Calcium | 18 | ||
| Serum | Carcinoembryonic antigen (CEA) | 16 | 24.7 | |
| Serum | Chloride | 7 | 5 | 1.5 |
| Urine | Chloride | 14 | ||
| Serum | Cholesterol | 8.5 | 10 | 9.01 |
| Serum | HDL-cholesterol | 15 | 30 | 11.63 |
| Serum | Cholesterinase | 12 | 9.8 | |
| Serum | Cortisol | 16 | 25 | 22.8 |
| Serum | Creatinine kinase (CK) | 21 | 30 | 30.3 |
| Serum | Creatinine | 15 | ± 0.3 mg/dL or ± 15% (greater) | 8.87 |
| Urine | Creatinine | 21 | 28.4 | |
| Serum | Digoxin | 30 | ± 20% or ± 0.2 ng/mL (greater) | |
| Blood | Erythrocytes | 7 | 6 | 4.4 |
| Serum | Estradiol | up to 200 pmol/L: 44 pmol/L > 200 pmol/L: 22% |
26.86 | |
| Serum | Ferritin | 24 | 16.9 | |
| Serum | γ-Glutamyl transferase (GGT) | 15 | 22.11 | |
| Serum | Glucose | 9 | ± 6 mg/dL or ± 10% (greater) | 6.96 |
| Urine | Glucose | 22 | ||
| Blood | Hematocrit | 10 | 6 | 3.97 |
| Blood | Hemoglobin | 6 | 7 | 4.19 |
| Blood | Hemoglobin A1c | 18 | 3 | |
| Serum | Immunogobulin A (IgA) | 20 | ± 3 SD | 13.5 |
| Serum | Immunogloblin G (IgG) | 18 | 25 | 8.0 |
| Serum | Immunogloblin M (IgM) | 21 | ± 3 SD | 16.8 |
| Serum | Iron | 15 | 20 | 30.7 |
| Serum | Lactate | 15 | 30.4 | |
| Serum | Lactate dehydrogenase (LDH) | 21 | 20 | 11.4 |
| Blood | Leukocytes | 9 | 15 | 15.49 |
| Serum | Lipase | 24 | 37.88 | |
| Serum | Lithium | 12 | ± 0.3 mmol/L or ± 20% (greater) | |
| Serum | Magnesium | 15 | 25 | 4.8 |
| Blood | Mean corpuscular volume (MCV) | 70 | 2.42 | |
| Serum | Phenobarbital | 20 | 20 | |
| Serum | Phenytoin | 20 | 25 | |
| Serum | Phosphate | 15 | 10.11 | |
| Urine | Phosphate | 18 | 22.1 | |
| Serum | Potassium | 8 | ± 0.5 mmol/L | 5.61 |
| Urine | Potassium | 17 | 28.4 | |
| Serum | Progesterone | 20 | ||
| Serum | Protein | 9 | 10 | 3.63 |
| Urine | Protein | up to 1 g/L: 0.24 g/L > 1 g/L: 24% |
40.0 | |
| Plasma | Prothrombin time (PTr), ratio | 20 | ||
| Serum | Sodium | 5 | ± 4 mmol/L | 0.73 |
| Urine | Sodium | 11 | 32.0 | |
| Serum | Testosterone | 22 | 13.61 | |
| serum | Thriiodothyronine (Total T3) | up to 1.5 nmol/L: 0.225 nmol/L > 1.5 nmol/L: 15% |
± 3 SD | 12.94 |
| Serum | Thyrotropin (TSH) | 14 | ± 3 SD | 23.7 |
| Serum | Total prostatic specific antigen (PSA) | 15 | 33.6 | |
| Serum | Throxine, Free (FT4) | 13 | ± 3 SD | 8.0 |
| Serum | Total thyroxine (TT4) | 13 | ± 3 SD | 7.0 |
| Serum | Triglycerides | 15 | 25 | 25.99 |
| Serum | Urate | 14 | 17 | 11.97 |
| Urine | Urate | 17 | 19.39 | |
| Serum | Urea | 15 | ± 2 mg/dL or ± 9% (greater) | 15.55 |
| Urine | Urea | 26 | 22.1 |
As we've seen with other comparisons recently, the truth about the CLIA goals is that they are still relevant. CLIA performance specifications are often criticized as being too old or too wide, yet they are freuquently similar to these Dmax goals, which are built on today's actual method performance. Meanwhile, the differences between the Dmax goals and the desirable biologic TEa specifications are more significant.