Design of a randomized clinical trial to improve rates of amblyopia detection in preschool aged children in primary care settings

Abstract

Purpose To present the design of a cluster randomized controlled trial (cRCT) to evaluate the effectiveness of a web-based intervention for improving provider knowledge about strabismus and amblyopia (S/A) and preschool vision screening (PVS), increase PVS rates, and improve rates of S/A diagnoses made by eye specialists. This is the first cRCT targeting amblyopia prevention. Methods Participants were Medicaid providers in AL, SC, or IL who had Internet access and had filed at least 8 claims for well child visits (WCV) for children ages 3 or 4 years old during a 12-month period before enrollment. Randomization to the Intervention (vision) or Control (blood pressure) arm occurred at the cluster level, defined as the provider (or group of providers) and his/her patients seen for WCVs. Results 65 Intervention providers (IPs) with 3547 children aged 3 or 4 years, and 71 Control providers (CPs) with 5053 children enrolled. The study will report measures of knowledge and self-reported vision screening behaviors from web-based data. The primary outcomes will be rates of PVS among PCPs, and rates of diagnosis of S/A by eye specialists among the children belonging to Control and Intervention practices. Conclusions We had the same difficulty recruiting PCPs as reported by others. Baseline rates of PVS were low (14.1%), as were rates that S/A were diagnosed by eye providers (1.4%). Our data show a need to improve both primary outcome measures.