Background: To evaluate if United States Medical Licensing Examination (USMLE) Step 1, USMLE Step 2 CK, USMLE Step 3, and residency third-year in-service training exam (ITE) scores predict the results of American Board of Internal Medicine Certifying Exam (ABIM-CE).
Methods: We performed a retrospective review of USMLE Step 1, USMLE Step 2 CK, USMLE Step 3, third-year residency ITE scores and ABIM-CE results of IM residents at our residency program from 2004 through 2017. Statistical analysis was perfrormed using Pearson correlation coefficient, and logistic regression to assess the relationship between USMLE Step 1, USMLE Step 2CK, USMLE Step 3, 3rd year ITE scores and ABIM-CE results. We used Multivariate logistic regression to predict pass or fail results in ABIM-CE based on USMLE and third-year ITE test scores controlling for other covariates.
Results: Among 114 Internal Medicine MD residents included in the study, 92% (n = 105) passed the ABIM-CE. The OR of passing ABIM-CE was 2.70 (95% CI = 1.38-5.29), 2.31 (95% CI = 1.33-4.01), and 1.63 (95% CI = 0.81-3.29) with a ten-point increase in USMLE Step 1, USMLE Step 2 CK and USMLE Step 3 scores respectively. The OR of ABIM-CE passing chance was 2.96 (95% CI = 0.95-9.20), with a ten-point increase in the average score of the above three exams. A 5 % increase in ITE percentage raised the likelihood of passing ABIM-CE (OR 2.92, 95% CI 1.15-7.38). All residents who failed ABIM-CE had Step 1 scores < 220. Among 31 residents with Step 2 CK score < 220, 20% (n = 6) failed ABIM. Similarly, 9% of residents with USMLE Step 3 score < 220 failed ABIM-CE; all residents who failed had scored < 220. The probability curve predicted that the chance of passing ABIM- CE was around 80% with USMLE scores greater than 200 and increased to almost 100% with USMLE scores of 250 or more.
Conclusion: USMLE Step 1, USMLE Step 2 CK, and third-year ITE scores can predict the chances of passing ABIM-CE. The third-year ITE score has a higher preditive value compared to USMLE Step 1 and USMLE Step 2 scores. USMLE Step 1 scores more predictive of ABIM-CE results compared to USMLE Step 2CK scores. Thus, residency programs can identify internal medicine residents at risk of failing ABIM-CE and formulate interventions at an early stage during residency training. Measures such as enrolling them in question banks or board review courses can be helpful in improving their chances of passing ABIM-CE.
Keywords: American board of internal medicine certifying exam (ABIM-CE); USMLE Step 1, USMLE Step 2CK, USMLE Step 3, 3rd year in-training exam results.