Predictors of success on the American Board of Orthopaedic Surgery examination

Abstract

Predictors of success of orthopaedic residents on the American Board of Orthopaedic Surgery (ABOS) examination are controversial. We therefore evaluated numerous variables that may suggest or predict candidate performance on the ABOS examination. We reviewed files of 161 residents (all graduates) from one residency program distributed into two study groups based on whether they passed or failed their first attempt on the ABOS Part I or Part II examination from 1991 through 2005. Predictors of success/failure on the ABOS I included the mean percentile score on the Orthopaedic In-Training Examination (OITE) (Years 2 through 4), the percentile OITE score in the last year of training, US Medical Licensing Examination (USMLE) score, Dean's letter, election to Alpha Omega Alpha (AOA), and number of honors in selected third-year clerkships. All but the USMLE score predicted passing the ABOS Part II examination. These data suggest there are objective predictors of residents' performance on the ABOS Part I and Part II examinations.

Fig. 1

A comparison is shown of the OITE percentile rank score in Year 5 between residents who passed and failed based on first time testing on the ABOS Part I and Part II examinations. Logistic regression analysis indicated that the OITE Year 5 percentile score was a predictor of performance (success versus failure) on the ABOS Part I (p < 0.001) and ABOS Part II (p < 0.001) examinations and thus this performance measure was an important predictor of outcome on the ABOS examinations as denoted by asterisks. The OITE Year 5 mean percentile among residents who passed and those who failed the ABOS Part I were 58 and 15, respectively. The OITE Year 5 mean percentile among residents who passed and those who failed the ABOS Part II were 57 and 30, respectively.

Fig. 2

A comparison is shown for quality of the Dean’s letter between first time results on the ABOS Part I and Part II examinations. Multivariate analysis indicated the description (good, excellent, outstanding) was a determinant in first-time results on the ABOS Part I and Part II examinations as denoted by the asterisks. Average Dean’s letters were approximately 0.5 points higher (based on 1–3 scoring system) among residents who passed compared with residents who failed.

Fig. 3

The percentage of residents with membership in AOA was higher among those who passed ABOS Parts I and II (49% and 51%) compared with those who failed (16% and 10%) as denoted by the asterisks (p < 0.05, Fisher’s exact tests).