Experiences from a door-to-door screening programme for developmental delay and motor impairment in Cuenca, Ecuador: A methodological study

Background Children with neurodevelopmental disorders in low-resource urban settings often remain undiagnosed and excluded from care. Reliable epidemiological data is crucial for addressing this issue, but in Ecuador, official data are limited, and fragmented health and education systems hinder effective early identification. To address this issue, an epidemiological door-to-door household survey was carried out in Cuenca, Ecuador. This paper presents a methodological review, reflecting on the challenges and lessons learned when implementing epidemiological research in a socially and economically vulnerable population. Methods The original study was a cross-sectional, descriptive survey conducted between September 2022 and March 2023 across 134 city blocks. Although designed to estimate the prevalence of developmental delay (ages 2–59 months) and motor impairment (ages 5–12 years), high attrition prevented valid prevalence estimates. The research team undertook a structured reflective analysis of the study process, to identify the causes of the high degree of participant loss to follow-up and to assess the strengths and weaknesses of the study’s methodology. Results The analysis revealed a critical weakness in the original study's design. A six-month delay between the initial screening (stage 1) and subsequent diagnostic assessments (stages 2 and 3) combined with the high mobility of the study population, was a primary driver of the 31–60% attrition between stages. Other significant challenges included: a lack of treatment pathways for participants, limited institutional support post-agreement, and the initially undeveloped soft skills of the student researchers. Strengths included reaching many unregistered children with disabilities, effective household mapping, strong inter-institutional collaboration to initiate the project, and valuable experiential learning for medical students. Recommendations arising from the review highlight the need for concurrent implementation of study stages, stronger preparatory community engagement, provision of treatment within the study protocol, and clear definition of institutional responsibilities. Conclusions This study underscores the importance of aligning methodological design with sociocultural realities. Future projects should develop community trust, secure robust institutional commitments, and integrate clear treatment into the research protocol to ensure participant retention and provide tangible community benefits. In addition to informing future research design, these findings illustrate how community-based projects can also serve as beneficial training experiences for health professionals.