[Excessive use of vitamin D testing in the private health system].

Introduction: Given the importance of reducing lowvalue care practices and acknowledging that vitamin D testing in the general population is rising despite the absence of evidence to support such conduct, we decided to investigate its overuse.

Materials and methods: Design: cross-sectional study.

Data source: electronic medical records.

Population: patients aged between 18 and 64 on the Hospital Italiano de Buenos Aires Health Maintenance Organization membership list, to whom at least one test of vitamin D had been performed between July 1st and December 31st 2022. A sample of electronic medical records was manually analyzed. In the presence/suspicion of a clinical condition that counts with recommendation for Vitamin D testing, its indication was considered appropriate; however, in its absence, it was considered inappropriate.

Results: A total of 10 095 vitamin D tests were performed on 9623 patients (mean age 47, 78.1% female). These patients were 10% of the 97 584 HMO members aged between 18 and 64 in 2022. A hundred and sixty of the 242 patients whose electronic medical records were analyzed (66%, CI 95% 60 - 72), did not have a clinical condition that justified vitamin D testing. The most frequent clinical conditions found for testing were osteopenia in 37/242 patients (15%); osteoporosis, 13/242 (5%) and chronic kidney disease 11/242 (5%).

Discussion: Two-thirds of the vitamin D tests performed did not have a clinical condition that justified the practice. These findings represent an opportunity to design strategies to institutionally reduce this low-value care practice.