Quality Issues

The Scottish Trace Element and Micronutrient Diagnostic and Research Laboratory strives to maintain a high quality service in terms of ....

The Laboratory currently has full accreditation status with UKAS (UK Accreditation Service) as part of the Department of Clincal Biochemistry at Glasgow Royal Infirmary (UKAS reference 9572). The majority of analytes offered by STEMDRL are included in the scope of accreditation. See individual analyte pages for further details. The Schedule of Accreditation can be found here: https://www.ukas.com/wp-content/uploads/schedule_uploads/00007/9572-Medical-Multiple.pdf

We participate in all appropriate external quality assessment schemes where they are available.

The performance of our service is overseen and reviewed by the National Services Division of NHS Scotland. The analytical aspects of the service are overseen by the Supra-Regional Assay Service for UK Trace Element Laboratories.

If you have any comments or complaints please contact us.

Reference Intervals

Reference intervals used in the Laboratory have been determined in a variety of populations - healthy laboratory staff or drawn from the literature. Where possible age- and gender-adjusted reference intervals are used. Reference intervals for infants and children are often not available.

Turnaround Times

Turnaround times are calculated from the time of receipt of sample to the time that result is available to be emailed, posted or accessed electronically by SCIStore. Target turnaround times can be found on this page. In practice, our actual turnaround times are usually far better than the target so the average turnaround times for individual analytes are recorded in the tables found on each analyte's webpage. On occasions, clinical cases of toxic trace element poisonings require a faster turnaround time to optimise patient management. In such circumstances, please phone and we can usually arrange for our analytical runs to be reorganised to expedite analysis.

Analytical Goals

Analytical goals are employed as quality indicators by STEMDRL to ensure that the results produced by the laboratory are fit for their intended use. The analytical goals stated within this document are for intermediate precision expressed as a coefficient of variation (CV). Acceptable and desirable analytical goals have been calculated from biological variation data when available. Desirable CV = 0.5CVI and acceptable CV = 0.75 CVI, where CVI is the intraindividual variation. Desirable CV is based on more stringent criteria and may not always be obtainable using current analytical techniques. In instances where biological variation data is not available, goals have been based on STEMDRL state-of-the-art which relates to the analytical performance technically achievable by the laboratory.

Measurement Uncertainty

Measurement uncertainty (MU) is derived from the intermediate precision of internal quality control material. MU is calculated using at least thirty data points collected over a period of six months. When less than thirty data points have been measured in six months, a longer period of time is used. The reported expanded measurement uncertainty, U, is based on a standard uncertainty multiplied by a coverage factor of k=2, providing a coverage probability of approximately 95%. The uncertainty evaluation has been carried out in accordance with UKAS requirements. The latest STEMDRL intermediate precision and MU data can be found here: