Effect of the characteristics of family physicians on their utilisation of laboratory tests

Background: The use of laboratory tests by family physicians has increased in recent years. Aims: To evaluate the relationship between family physicians' characteristics and the number and type of laboratory tests requested, taking into account chronic diseases. Design of study: Retrospective, cross-sectional study. Setting: One hundred and sixty-two physicians treating 230 123 patients in one district of a health management organisation in Israel. Method: Physicians' use of 16 common types of laboratory tests was assessed in relation to physicians' demographic, professional, and clinic characteristics. The utilisation rate over 1 year was divided into quintiles for each laboratory test, and each physician was given a global laboratory score (for each test the physician got a score from 1 (utilisation in the lower quintile) to 5 (higher quintile). The global score was the sum of scores of the individual tests. Results: On logistic regression analysis, four background characteristics were associated with the global score for the utilisation of laboratory tests. The highest hazard ratios were for being a female doctor (3.2, 95% confidence interval [CI] = 1.5 to 6.5), working in an urban clinic (3.2, 95% CI = 1.1 to 9.8), and having a greater workload than doctors in rural clinics (1.4, 95% CI = 1.1 to 1.8). Being a graduate of a Western country or Israel had a negative association with the global score (0.4, 95% CI = 0.1 to 0.99). Conclusion: Female sex and working in a urban clinic were major factors in the use of laboratory tests in clinical practice. As more women enter the medical profession, an improved understanding of the sex differences in ordering medical tests is important.