The effect of prior night call status on the American Board of Surgery in-training examination scores: eight years of data from a single institution.

PURPOSE: Despite recent attention to resident duty hours, little data evaluate the effect of being on-call the night before taking an in-training examination on examination performance. The few previous studies evaluated single-year test scores, from heterogeneous cohorts, with inconsistent findings. The purpose of this study was to determine the effect of being on-call the night before taking the American Board of Surgery In-Training Examination (ABSITE) on resident scores at a single institution over a duration of several years.

METHODS: Overall percentile rank, standard scores, and prior night call status were recorded for all residents (categorical and preliminary) taking the ABSITE at our institution from 1999 to 2006. A 2-way ANOVA was performed to determine whether (1) the standard scores varied significantly between residents not on-call and those who were on-call, 2) performance varied significantly by PGY level, and 3) there was a significant interaction between call status and PGY level. Percentile rank of residents on-call the night before the examination were compared with those off-call using the Mann-Whitney U-test. For residents with scores from multiple years, standard scores from years on-call were compared with years off-call using the Wilcoxon signed rank test.

RESULTS: A total of 282 ABSITE results were recorded with 69 (24%) residents taking in-house call the night before the examination. A 2-way analysis of variance indicated that although standard score performance varied significantly by PGY level (p < 0.001), no significant differences were found in scores at any PGY level attributable to being on-call (p = 0.70). This analysis was also performed on only categorical general surgery residents' scores. Again, no significant differences were attributable to being on-call. Similarly, a Mann-Whitney U-test indicated no statistical difference in percentile scores based on call status (p = 0.43). Matched resident scores from year to year did not differ significantly based on call status (p = 0.21).

CONCLUSIONS: Based on several analytic models, being on-call the night before the ABSITE does not significantly affect resident performance.