Background: Quality control materials play a vital role in the laboratory internal and external quality assessment program. However, Ethiopia and other developing countries are challenged by the unavailability and high cost of commercial control material. Therefore, preparing in-house quality control human serum will be a cost-effective way to obtain QC material for use in poor settings in a country like Ethiopia. To prepare urea in-house control human serum and scientifically evaluate it with commercially available sera already in use in the clinical chemistry laboratory of the Ethiopian Public Health Institute.
Methods: The urea in-house quality control human serum was prepared as per ISO Guide 80, a guideline document protocol from 57 participants’ normal serum specimens at the Ethiopian Public Health Institute clinical chemistry laboratory. The quality control material was analyzed on a fully automated chemistry analyzer (Cobas 6000). The initial 20 values were used for calculation of means, standard deviation (SD) and coefficient of variation (CV). Results were compared with those of commercially available lyophilized human sera.
Results: The average concentrations of urea were found to be near the middle of the physiological range of healthy subjects and the in-house serum could be a good substitute for the commercial serum of normal range. The prepared in-house quality control human serum is stable for about three months without any alterations in the concentration of urea.
Conclusions: Well prepared in-house quality control human serum is a good substitute for commercially available control serum of normal range, especially in a developing country like Ethiopia.