RESUMEN
OBJECTIVE: To verify factors associated with early newborn access to biological neonatal screening. METHOD: A cross-sectional quantitative study was carried out with all newborns who underwent tests in healthcare units, hospitals, and laboratories of a city in the state of São Paulo, Brazil, with programs linking healthcare information. The following variables were investigated: child's age at collection (dependent); place of collection; date of collection; and type of user (independent). Descriptive and inferential statistics were applied. RESULTS: Records of 15,652 screenings were found in the two years analyzed. In the first year analyzed, 7,955 births and 7,640 (96.0%) tests were recorded, of which 5,586 (73.1%) were undertaken with newborns between three and five days old. In the next year analyzed, 8,316 births and 8,012 (96.3%) screenings were recorded, of which 7,025 (87.6%) were undertaken with newborns in the same age group. A statistically significant association was found between the variables "child's age" and "type of user" in one year, and between the variables "child's age" and "place of collection" in both years. CONCLUSION: Early access to these tests enables the screening of diseases and referral for treatment. The present study contributes to the management of child care programs by presenting strategies linking data and actions to improve access to biological neonatal screening.