Clinical laboratory proficiency test performance. Its relationship to structural, process and environmental variables

This comparative analysis of clinical laboratories was intended to develop a more quantitative understanding of environmental, structural, and process variables and their relationships to the quality of laboratory services. The quality of laboratory services was defined as analytic capability demonstrated on proficiency-test specimens of the College of American Pathologists. Independent variables describing the laboratory environment, as well as structural and process aspects of management, were obtained from management reports, staffing records, and workload reports. Although correlations between the eight proficiency testing indices and the independent variables were generally low, a number of significant correlates were evident in three areas: bacteriology, parasitology, and qualitative hematology. Environmental variables describing organizational size were related to proficiency, as were variables dealing with accreditation by the College of American Pathologists and time accredited by the College of American Pathologists. The education and experience of personnel and the percentage of specialized supervisors were related to proficiency-testing success in bacteriology and parasitology. Empirical evidence suggests that the size of the laboratory indirectly affects proficiency in these three tested areas. Presumably, this relationship is mediated through specialization of work and reinforcement of learning. Few significant correlates were evident in the five remaining areas tested: chemistry, quantitative hematology, blood bank, immunology, and syphilis serology. Despite the concentration of personnel resources and other assets in larger laboratories, size appeared to have no effect on proficiency-testing performance in these five areas.