Sumera Naz, Arshad Mumtaz, Agha Sadaruddin.
Preanalytical errors and their impact on tests in clinical laboratory practice.
Pak J Med Res Jan ;51(1):27-30.

There are pre-analytical, analytical and post analytical factors that contribute to accurate test results in clinical laboratories. Pre-analytical variables account for 32-75% of laboratory errors, and encompass the time from when the test is ordered by the physician until the sample is ready for analysis. Most mistakes often occur before the samples are analysed. There is a need for stronger coordination between clinicians and personnel working outside the laboratory for improving the test quality.

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