Choosing a laboratory for a drug and alcohol testing!

Social workers are using hair strand-testing to profile patterns of drug and alcohol use. Choosing the laboratory to conduct these tests is a vital part of getting timely and accurate assessments.!

Parental substance abuse is a significant factor when it comes to assessing children at risk in the UK. Alcohol Concern and the Children’s Society estimate that 2.6 million children in the UK live with a parent whose drinking could lead to neglect or abuse. For social workers it is notoriously difficult to know the truth when a parent claims to have kicked their habit or whether any reformed lifestyle can survive temptation. !

Social workers with difficult child protection cases involving parental substance misuse have been helped by hair tests but the consequences of using the wrong laboratory can be severe. Over the last few years been have been well-publicised cases of evidential errors that resulted in a number of parents being denied access to their children as well as the closure of the laboratory. So how can practitioners minimise this risk?!

Choosing a laboratory

In this era of government austerity cost has become a primary factor in the selection of services contracted by local authorities and their Social Service departments. This applies particularly to the choice of laboratory to determine the use of drugs and alcohol in clients of social services. But cost should not be the only consideration in choosing a laboratory. Other important considerations include the laboratory’s accreditation status, the use of accredited methods, quality control, and the time to produce the report.!

Accreditation is the best indicator that the lab is capable of delivering a good service. It is an external assessment of performance that may only be made on an occasional basis, perhaps once a year. Accreditation is not proof of the quality of all the data they produce. It does mean that they are capable of providing accurate, representative, comparable and defensible data.! If the provider does not perform the analysis in-house then that should be declared and documented. In the UK the body charged with accrediting laboratory performance is the United Kingdom Accreditation Service which holds copies of the certification of the labs that they accredit.

Accreditation criteria

It is easy to access the UKAS website and view the current accreditation status of any laboratory you may be thinking of using ( There is even a helpful app that can be downloaded from the UKAS home page to your iPhone, so you can always make the check. By verifying that the lab is accredited to ISO/IEC 17025:2005 you will know that its methods and procedures to control and document performance have been accredited. You can also be assured that they will have independently assessed procedures to correct things when mistakes are made. No laboratory can be totally error free, but an ISO/IEC 17025 accredited lab will have checks in place to prevent mistakes, detect when performance drops and closely track your sample from entry into the lab to generation and delivery of the final report.!

Quality control

If you need a laboratory for a specific analysis then you can determine from the UKAS record that the lab is accredited for the specific test you need. Not all labs are accredited for all the tests that they perform and this does not necessarily imply a poor test. Accreditation takes time and money. For less frequent tests, full accreditation may not be justified but in any case the chosen lab should be able to produce quality control data to prove that they do get accurate and defensible data for every test they perform.!

Quality control tests document the performance of all methods in the laboratory, every time the method is performed. The lab should be expected to be able to report quality control results associated with your samples, such as blanks, standards and controls of known concentration. They should also be able to provide bias and precision estimates to enable judgments to be made as to the accuracy of the data. You may receive only a summary report of findings such as a certificate of analysis. Behind that certificate there is the need maintain a body of evidence that makes that certificate legally defensible. It is through the process of UKAS accreditation that this is assured.!

Finally, there is no point in a test result that takes so long to produce that it is no longer relevant to the case with which it is associated. The lab you choose to use should be able to quote you current turnaround times, and keep to them!

Article by John Wicks was first published in COMPASS, the complete guide to social work & social care 2015 edition.

Click here for a pdf format of the article.
Posted in Accreditation, Alcohol testing, Drug testing, Hair drug testing