Scheme Information Sheets
UK NEQAS for Tox and TDM
| Scheme Particulars | Indicative Details |
|---|---|
| Accreditation body | UKAS |
| ISO/IEC Accreditation status | ISO/IEC 17043:2023 |
| UKAS Accredited Proficiency Testing Provider No | 7860 |
| Objective of Scheme | Provides EQA coverage for a wide number of both therapeutic (TDM) and Toxic (TOX) drugs. Seperate specimens are supplied for both the TDM and TOX drugs. The Toxic drug specimens contain drugs that require montoring to avoid levels becoming toxic and include Salicylate, Paracetomaol, Ethanol and Ethylene Glycol. The TDM specimens contain a wide range of drugs that require monitoring for maintaining blood concentrations within a narrow theraputic range. This scheme provides both manipulated and endogenous specimens that cover both the therapeutic and toxic drugs concentration ranges for all drugs Specimens will often be targeted to important drug action or cut off levels as well as probing drug interactions or interferences that occur in immunoassays |
| Pre-, Analytical, Post- status | Analytical |
| Number of distributions per year (nominal) | 11 |
| Specimens per distribution | 3 (Separate specimens for Tox and TDM) |
| Number of Specimens per annum | 33 |
| Frequency of distribution | Monthly |
| Scoring system | ABC |
| Material distributed | Pooled, liquid human serum with or without exogenous added analyte |
| Programme Director(s) / Organiser(s) | Finlay MacKenzie |
| Criteria for participation | All, but overseas by courier |
| Nominal sample volume (mL) | Tox 0.6 TDM 0.9 |
| Sample presentation TACs | The TDM analytes are in a separate tube to the TOX analytes |
| Data in Chemistry on-line Dashboard | Yes |
| Analyte | Approx Range | Default Units | Target Value | B Score Limit (%) | C Score Limit (%) |
|---|---|---|---|---|---|
| Caffeine | 0 – 50 | mg/L | XALTM | 10.0 | 15.0 |
| Carbamazepine | 0 – 30 | mg/L | ALTM | 15.0 | 15.0 |
| Digoxin | 0 – 4.0 | µg/L | ALTM | 20.0 | 20.0 |
| Ethosuximide | 0 – 180 | µg/L | XALTM | 10.0 | 15.0 |
| Ethylene Glycol | 0 – 2000 | mg/L | XALTM | 10.0 | 20.0 |
| Lamotrigine | 0 – 50 | mg/L | XALTM | 10.0 | 15.0 |
| Lithium | 0 – 4.0 | mmol/L | ALTM | 10.0 | 15.0 |
| Methotrexate | 0 – 50 | µmol/L | ALTM | 10.0 | 15.0 |
| Paracetamol | 0 – 400 | mg/L | ALTM | 7.5 | 10.0 |
| Phenobarbital | 0 – 70 | mg/L | ALTM | 10.0 | 15.0 |
| Phenytoin | 0 – 40 | mg/L | ALTM | 10.0 | 15.0 |
| Primidone | 0 – 40 | mg/L | XALTM | 10.0 | 15.0 |
| Salicylate | 0 – 650 | mg/L | ALTM | 7.5 | 10.0 |
| Serum Ethanol | 0 – 4000 | mg/L | ALTM | 7.5 | 10.0 |
| Theophylline | 0 – 40 | mg/L | ALTM | 10.0 | 15.0 |
| Valproate | 0 – 180 | mg/L | ALTM | 15.0 | 15.0 |
| Abbreviation | Expansion |
|---|---|
| ALTM | All Laboratory Trimmed Mean |
| GLTM | Group Laboratory Trimmed Mean – which is the Method Principle Mean |
| MLTM | Method Laboratory Trimmed Mean – usually a manufacturer system / analyser mean |
| XALTM | An external value that may be from a Reference Method System |
| OGLTM | A Method Principle Mean used as the target for all laboratories |
| OMLTM | A specific Method Mean used as a target for all laboratories |
| MED | Median |
