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Medical treatment largely depends on the results of clinical tests. Proper care should be taken to generate correct diagnostic test results. Here both laboratories and patients will have to be cautious. Patients’ lack of awareness is responsible for around 50-60% of pre-analytical errors and the rest of the errors can be attributed to diagnostic labs.

Pre-analytical error

This is the most important source of diagnostic test errors. One has to take proper amount of samples in a container or vial. In case of blood testing, RBC is to be separated from it to get serum. This should be done properly. The sample should reach the lab on time. Delayed submission should not be permitted. Patients’ lack of awareness is responsible in many ways for wrong testing results. First, when a person gives blood for testing, he must take rest for at least 10 minutes. Otherwise, the test results may be wrong. For example, for a PC DC ESR test, if a patient does not take rest before giving blood, the value of ESR may be elevated. Second, for testing of lipid profile, a patient has to maintain fasting for 12 hours before giving blood.  Additionally, that person should take fat-less food for seven days and should not drink alcohol. Any variation from these guidelines may show high value of triglyceride. Third, in case of thyroid testing, patients should not eat iodized salt along with any food to have a correct thyroid test. Fourth, at the time of urine culture, a patient has to avoid taking antibiotic drug for some hours. Fifth, for sugar testing (fasting or PP), the patient should not stop taking anti-diabetic drugs or insulin. The most important thing is remember that the PP and fasting tests should be done on the same day. Sixth, before urine rating test, a patient should restrict high sugar food. There has been a misconception among many that in case of examining the presence of malaria, blood should be taken from the patient when he has high fever. But that is not the case. Blood can be taken any time.