QUALITY CONTROL: GOOD LABORATORY PRACTICE- AN OVERVIEW OF QUALITY ASSURANCE

The laboratory is pivotal in medical practice as test results have a major influence on clinical diagnosis and patient management. The laboratory has an ethical obligation to produce reliable and reproducible analytic measurements and observations that are timely and cost effective. It should provide clinicians with unambiguous and meaningful reports that are relevant to the clinical problem. There is also a moral obligation to train and advance the careers of the professional and other laboratory personnel, to ensure their health and safety in the course of their work, and to advance the speciality by research and technological innovations. These objectives represent good laboratory practice; the mechanism for achieving this is encompassed in total qual ty management (Fig. 1). With modern instruments the analytic process and its control are becoming increasingly reliable; errors are more likely to occur during the pre- and post-analytic phases. Figure 1. Flow diagram of quality management in the laboratory. The pre-analytic phase begins with blood collection, which should be standardized to avoid subsequent measurement artefact.(1) Prolonged use of a tourniquet results in haemoconcentration; the patient’s posture (standing, sitting or lying) and even th