Prevalence and determinants of suspected developmental delays among 12-month-old children in northeast of Iran: a large-scale population-based study.

Background: Early identification of suspected developmental delays (SDDs) is crucial for planning early interventions. This study aimed to determine the prevalence of SDDs and the associated determinants in children aged 12 months in the northeast of Iran, using the Age and Stage Questionnaire-3 (ASQ-3) as the evaluative tool.

Methods: This study conducted an analytical cross-sectional design to investigate all children who had completed the ASQ-3 screening form at 12 months of age within the time frame of 2016-2023 in the northeast of Iran. The necessary data were extracted from the electronic health record database associated with Mashhad University of Medical Sciences. To examine the factors associated with SDDs within each domain of the ASQ-3, a multiple logistic regression model was employed, and the results were presented using ORs along with 95% CIs.

Results: Over 7 years, 236 476 children (96.74%) underwent routine ASQ-3 screening at 12 months. After excluding certain cases, 226 076 children (95.60%) were included. Among them, 51 593 children (22.82%) had a score below -1 SD, indicating SDD prevalence in at least one domain. The social-personal domain had the highest prevalence with 22 980 children (10.16%), while the gross motor domain had the lowest with 5650 children (2.50%). Logistic regression analysis identified strong predictors of SDDs, including hospitalisation at birth (OR=1.85, 95% CI:1.69 to 2.02), prematurity (OR=1.56, 95% CI: 1.37 to 1.79), urbanisation (OR=1.51, 95% CI: 1.45 to 1.57), boys (OR=1.36, 95% CI: 1.31 to 1.40) and lack of exclusive breast feeding until 6 months (OR=1.30, 95% CI: 1.25 to 1.34).

Conclusion: The prevalence of SDDs highlights the urgency for prompt action, while considering contributing factors. Policymakers can address modifiable risk factors associated with SDDs, including urbanisation risks, support programmes for immigrant families and the importance of exclusive breast feeding until 6 months. Additionally, it is recommended establishing gender-specific local standard cut-off points for the ASQ.