Quality Control Applications in Biochemistry Laboratories of Federal Hospitals in the North Central Zone: A Professional Audit

Internal and external quality control programmes are the cornerstone of reliable biochemical laboratory diagnosis, yet the implementation status of quality control practices across federal hospital biochemistry laboratories in north-central Nigeria has not been systematically audited. This study conducts a professional audit of quality control applications in biochemistry laboratories of seven federal hospitals across Plateau, Benue, Kogi, Kwara, Nasarawa, Niger, and Abuja FCT states. A structured audit instrument developed from ISO 15189 medical laboratory standards was applied to evaluate daily internal quality control practices, participation in external quality assurance schemes, equipment calibration records, reagent management, and staff competency documentation. Interviews were conducted with chief medical laboratory scientists and senior laboratory officers at each facility. Findings reveal significant variability in quality control compliance across the audited facilities. Westgard rule-based internal quality control was consistently applied in only three of the seven laboratories. External quality assurance programme participation, specifically with the national MLSCN EQAS scheme, was documented at five facilities but participation certificates were current at only two. Equipment calibration records were incomplete in four laboratories, and staff competency assessment documentation was absent in five. Reagent cold chain breaches were identified in three facilities, with implications for assay reliability. The audit highlights structural deficits in quality management system implementation and recommends a North Central zone-wide quality improvement programme coordinated by the Medical Laboratory Science Council of Nigeria. Keywords: quality control, biochemistry laboratory, ISO 15189, federal hospitals, North Central Nigeria.