Pre-analytical ErrorsOfficial reports indicate that clinical laboratory results determine up to 60-70% of physician decisions about hospitalization, discharge, and prescription. Errors can occur in all stages of the testing process – the preanalytical, analytical and postanalytical phases. However, studies show that errors in pre-analytical stage predominate and are as high as 70%.

Preanalytical errors can occur outside the laboratory and under the control of laboratory, and include those in the test request, patient identification, collection, transportation, and preparation for analysis. A recent study recommends that all laboratories develop quality indicators such as those developed and recommended by the IFCC working group on Lab Errors and Patient Safety, which are as follows:

  • Appropriateness of physician order – Whether the request was placed without indication or placed with inappropriate indication
  • Patient identification – Orders with errors in patient ID
  • Data entry in the physician’s order – Whether test input is missing, added or misinterpreted
  • Sample identification – Improper labeling
  • Sample collection – Inappropriate time/temperature, sample type, container, volume
  • Sample transport – Damaged, inappropriate time/temperature, improper storage, sample lost or not received
  • Sample suitability – Inadequate sample/anticoaulant ratio, sample is hemolyzed, clotted, lypemic, or the blood culture is contaminated

Some patient variables can be controlled while others cannot. Of the controllable preanalytic phase variables, specimen collection is considered to be the most critical. For instance, blood collection tubes (BCTs) can cause preanalytical errors as their components – tube walls, rubber stoppers, lubricants, anticoagulants, separator gels, clot activators, and surfactants – all affect the quality of specimens and accuracy of laboratory tests.

One of the main challenges of preventing preanalytical issues is that the processes are usually manual and it is not easy to track quality in real time. According to the above-mentioned study, laboratories need to first detect preanalytical issues. This can be done by developing good quality indicators covering all steps of the preanalytical phase to identify problems. The next step should be implement event management to investigate and correct errors and prevent them from recurring.

Laboratory equipment and services can prove effective only if they are accurate, precise, and quick. Errors are a major impediment in medical laboratory testing, affecting decision-making by physicians and patient care, and increasing healthcare costs. Maintaining the quality of laboratory tests by preventing preanalytical errors needs to be seen as an essential and achievable goal.