Purpose: Determine the prevalence of symptoms of neurodevelopmental problems (NDPs) with a semi-structured review of fourth grade students' medical records, its interrater agreement and validity as compared with clinical assessment. Methods: A school-based sample of 11-year-old children provided child health care (CHC) records and school health care (SHC) records. A pediatric neurologist, child psychiatrist and an adult psychiatrist scored the records, with the "Early Symptomatic Syndromes Eliciting Neurodevelopmental Clinical Examinations-Questionnaire" (ESSENCE-Q, 12 items scored 0-2, summary score range 0-24). Agreement was measured with model-based kappa and intraclass correlation coefficient (ICC). Ratings were validated against a multidisciplinary assessment involving a physician, psychologist, teacher- and parental behavioral rating scales rendering a clinical global impression severity rating (CGI-S, range 1-7) of NDPs. Results: Out of 223 participants, medical charts were available from 201, of whom 169 were rated by all three raters. Kappa agreement was moderate/strong (~0.8) for 7 of the 12 questionnaire items. Measured with the ICC, concordance in the summary score was good for agreement (~0.8) and excellent (~0.9) for consistency. Test-retest reliability was excellent (ICC = ~0.9). Area under the curve for the ESSENCE-Q in predicting clinical-level problems (CGI ≥4) was ~80% for all three raters, albeit with differing optimal cutoffs. Conclusion: Using the ESSENCE-Q as a template, NDPs appear to be common in medical records, are identified reliably, and predict clinical-level concern. Medical records screening may facilitate a structured review of medical records in work-ups or be applied in conjunction with other screening measures for neurodevelopmental disorders. However, differences in calibration currently preclude defining a universal cutoff for using the ESSENCE-Q for medical records screening.