Association between Subspecialty In-Training Examination Scores and First Attempt Results in Neonatal-Perinatal Medicine Boards.

No multicenter study has examined the relationship between subspecialty in-training examination (SITE) scores and certification exam (CE) outcomes in pediatric subspecialties. This study addresses this gap by investigating whether performance on the Neonatal-Perinatal Medicine (NPM) SITE predicts first-attempt results on the NPM-CE administered by the American Board of Pediatrics.A multicenter, retrospective cohort study was conducted across NPM fellowship programs in the United States. Data from 326 fellows across 15 programs who took the NPM-CE between 2014 and 2024 were analyzed. De-identified SITE scores and CE results were collected via REDCap. Year-specific Z-scores for SITE performance were calculated, and mixed-model generalized linear equations and logistic regression were used to assess the odds ratio (OR) and 95% confidence intervals (CI) for CE failure, adjusting for clustering within programs and program characteristics.Out of 326 fellows in this cohort, 36 failed the CE. Fellows with an average SITE score of < 55% correct answers in the first 2 years of training had four times higher odds of failing the NPM-CE compared with those with ≥ 55% (OR: 4.28; 95% CI: 1.77, 10.33; p < 0.001). Similarly, those with an average SITE Z-score ≤ -1.0 had 12 times higher odds of CE failure compared with those with Z-scores > - 1.0 (OR: 12.12; 95% CI: 5.39, 27.25; p < 0.001). Fellowship program characteristics did not significantly influence CE outcomes.Performance on the NPM SITE during the first 2 years of fellowship predicts first-attempt NPM-CE results. Early identification of at-risk fellows through SITE performance may enable targeted educational interventions to improve certification outcomes. This study highlights the utility of SITE as a predictive tool in pediatric subspecialty training.