Use of the Ages and stages questionnaire in Bradford as a measure of Child Development (ABCD): a mixed methods study protocol

Abstract The Ages and Stages Questionnaire® is the earliest routinely recorded measure of children’s development at age two, administered in England. However, there have been few studies on the acceptability of this measure within a UK setting, especially for families at risk of inequity. To ensure all children and families receive the necessary support, a reliable measure of child development is essential. This mixed-methods study aims to address the current evidence gaps by investigating if the Ages and Stages Questionnaire® is acceptable, implementable, and equitable for use by health professionals and families as an overall measure of child development in a UK setting. This study will use data from Born in Bradford’s Better Start birth cohort, which recruits from three ethnically diverse, socioeconomically deprived inner-city wards of the Bradford District. Rich baseline sociodemographic information will be linked to individual-level local health visiting data to describe how many children have records of an Ages and Stages Questionnaire®, investigate the factors associated with children having a record and describe differences in questionnaire scores by sociodemographic characteristics. To support interpretation of the quantitative analyses within the local context, qualitative semi-structured interviews will be conducted to explore health professionals’ perspectives and experiences of implementing the Ages and Stages Questionnaire® in Bradford. We will analyse the interview data using descriptive thematic analysis and integrate the data using the process of triangulation. We will use the Health Equity Implementation Framework to underpin our approach. This study has been designed with the Bradford Health Visiting Service to support development of locally relevant, evidence-based recommendations for improving the implementation of the Ages and Stages Questionnaire®. The findings from this research will also provide crucial insights into the use of the Ages and Stages Questionnaire® as a tool for measuring early child development, particularly in ethnically diverse, urban populations. Competing Interest Statement The authors have declared no competing interest. Funding Statement Yes Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The protocol for BiBBS recruitment and collection of routine data was approved by Bradford Leeds NHS Research Ethics Committee (15/YH/0455). Research governance approval was gained from Bradford Teaching Hospitals NHS Foundation Trust. The existing ethics includes approval for observational research using the BiBBS cohort. The current study is thereby covered by the above-mentioned ethical approval. BiBBS takes written informed consent from all participants (ie. parents of children). The qualitative component of this research was reviewed and approved by the Department of Health Sciences Research Governance Committee at the University of York (HSRGC/2025/686/A) and Health Research Authority (HRA) approval was granted (25/HRA/0330). Informed written or verbal consent will be obtained for participants of the qualitative component of this research. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data Availability No datasets were generated or analysed during the current study. All relevant data from this study will be made available upon study completion.