RT Journal Article SR Electronic T1 Inappropriate laboratory test utilization in outpatient tertiary care JF Saudi Medical Journal JO Saudi Med J FD Prince Sultan Military Medical City SP 356 OP 361 DO 10.15537/smj.2024.45.4.20230512 VO 45 IS 4 A1 Almasoud, Nouf F. A1 Aldosari, Mohammed A. A1 Mahmoud, Ahmed S. A1 Alendijani, Yaser A. A1 Alkhenizan, Abdullah H. YR 2024 UL http://smj.org.sa/content/45/4/356.abstract AB Objectives: To assess the rate of inappropriate repetition of laboratory testing and estimate the cost of such testing for thyroid stimulating hormone (TSH), total cholesterol, vitamin D, and vitamin B12 tests.Methods: A retrospective cohort study was carried out in the Family Medicine and Polyclinic Department at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. Clinical and laboratory data were collected between 2018-2021 for the 4 laboratory tests. The inappropriate repetition of tests was defined according to international guidelines and the costs were calculated using the hospital prices.Results: A total of 109,929 laboratory tests carried out on 23,280 patients were included in this study. The percentage of inappropriate tests, as per the study criteria, was estimated to be 6.1% of all repeated tests. Additionally, the estimated total cost wasted amounted to 2,364,410 Saudi Riyals. Age exhibited a weak positive correlation with the total number of inappropriate tests (r=0.196, p=0.001). Furthermore, significant differences were observed in the medians of the total number of inappropriate tests among genders and nationalities (p<0.001).Conclusion: The study identified significantly high rates of inadequate repetitions of frequently requested laboratory tests. Urgent action is therefore crucial to overcoming such an issue.