The analytic phase consists of all the processes involved in the testing of a specimen. Errors occur much less frequently in the analytic phase of laboratory testing than in either the preanalytic or postanalytic phases. The supposition of published studies on the error rate in this category is that the percentages remain low primarily because of
- The qualifications of testing personnel.
- Effectiveness of internal quality control programs and external assessment practices which assist in identifying analytical errors and detecting possible sources.
Following is a list of examples of errors that may be encountered during the analytic testing activities. The list includes both human and instrumentation errors. While random errors (those that occur independently of the operator) may be encountered during the analytic phase, primarily listed are systematic errors that bias the measurement resulting from either instrument malfunctions or human mistakes. Those include
- Errors in quality control and verification of performance specifications.
- Instrument malfunctions.
- Calibration errors causing a direction of bias in results.
- Manual pipetting errors.
- Reagent errors.
- Test interference caused by unsuspected antibodies.
- Specimen interference i.e. failing to visually see sample was lipemic.
- Math errors.
- Staff errors in testing preparation and processing.
- Inadequate staffing which may precipitate errors caused by fatigue.