BackgroundParents’ Evaluation of Developmental Status, (PEDS), is a validated screening tool designed for primary health care clinicians to assess child development. Despite widespread use by local government child-nurse services, PEDS has not been tested in Australian general practice. We examined the effect of an intervention that aimed to use PEDS to improve documented assessment of child developmental status during routine general practice consultations.MethodsThe study took place in a single general practice in Melbourne, Australia. The intervention included training of all general practice staff regarding PEDS processes and provision of PEDS questionnaires, scoring and interpretation forms. Mixed methods incorporated audits of clinical records of young children (1 to ≤ 5 years) before and after the intervention, and written questionnaires and a focus group (informed by the Theoretical Domains Framework and COM-B model) with receptionists, practice nurses and general practitioners.ResultsDocumented developmental status more than doubled after the intervention with almost one in three (30.4%) records documenting the PEDS tool. Overall, staff responses to questionnaires indicated that PEDS processes had been successfully implemented, half of the staff felt PEDS had developed their professional skills and clinicians expressed confidence using the tool (71%). Thematic analysis of the focus group transcript revealed divided reactions to PEDS screening with most barriers arising from general practitioners’ motivation to use PEDS tools and perceptions of environmental constraints.ConclusionsA team-practice intervention that applied PEDS training and implementation, more than doubled documented rates of child developmental status during routine visits. Solutions to underlying barriers could be incorporated into a revised training module. Future studies need to test the tool in more methodologically robust studies that include analysis of the outcomes of developmental surveillance and long-term sustainability of PEDS use in practices.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12875-023-02093-7.