Efficacy of a Web-Based Intervention to Improve and Sustain Knowledge and Screening for Amblyopia in Primary Care Settings

Large gaps in the continuum of preschool vision care have been demonstrated at the screening, diagnosis, and treatment steps. Although vision screening is an accepted part of preventive care,1 many children are missed. The National Ambulatory Medical Care Survey (NAMCS) recruited a nationally representative sample averaging 2,500 physicians and 24,000 patient visits per year, and reported that 11% to 17% of children were screened with a test of acuity over a 10-year period.2 These data are in close agreement with studies using Medicaid billing data3,4 although other studies report lower5 or higher6 rates. “Quantitative” vision screening is usually performed by medical staff using a test of visual acuity or, less commonly, using photo- or autorefraction.7,8 Low rates of screening may contribute to low rates of diagnoses of amblyopia or strabismus by eye specialists: Claims data show that 1.4% of children aged 3 or 4 years were diagnosed with either condition in states participating in a randomized trial to improve preschool vision screening (PVS) in office settings.9 In contrast, population-based data showed approximately 4% to 5% of children with one or both conditions depending on race/ethnicity and geographic location.10,11 Despite reports that universal PVS in Sweden using a test of acuity at age 4 years has reduced the prevalence of amblyopia from 2% to 0.2%,12 and despite recent reports of effective screening tests13–15 and treatment16 for amblyopia, in the United States less than 13% of amblyopic children aged 30 to 72 months in the population-based studies had received appropriate treatment.10,11 Universal PVS is a necessary first step toward reducing preventable vision loss caused by amblyopia among children living in the United States. Studies indicate that various other types of pediatric preventive care fall short of recommendations,17,18 and gaps in knowledge about the condition or recommended action are often implicated in attempts to understand and improve practice behaviors.19–24 Most theories about behavior change include knowledge about the targeted action or condition as a factor that influences behavior.23–27 This traditional knowledge–attitude–behavior approach to behavior change intervention is complementary to a range of behavioral theories from social cognitive theory25 to information–motivation–behavioral skills theory26 (see review and synthesis by Michie et al.27). Our previous research shows that many primary care providers (PCPs) lack knowledge about amblyopia and PVS recommendations,7 prompting our efforts to design an intervention to improve both, as a preliminary step toward improving actual practice behavior. Although knowledge improvement alone is often insufficient to effect behavioral change,27–30 our research indicates that high levels of knowledge enhanced the effects of good attitudes on self-reported PVS behaviors.7 Therefore, as with most behavior change interventions, efforts to improve PVS behavior should include a knowledge component. We chose the Internet as the best delivery mode to implement facets of adult-based learning relevant to physicians (see the Methods section) as well as allowing low-cost, wide-spread dissemination of standardized information to individuals separated by time and distance. Web-based instruction has various potential advantages compared with traditional lecture-based continuing medical education (CME), including convenient access, standardization, use of multiple strategies to convey difficult or dynamic concepts, interactivity, tailoring of content based on responses, feedback allowing comparison to peers, and ease of updating to reflect new research, policies, or methods.31 In this article, we describe results of our web-based intervention, designed to increase knowledge about “vision” (strabismus, amblyopia, and self-reported PVS behavior). Our study is especially pertinent considering a recent report from the Office of the Inspector General which reviewed medical records of Medicaid-eligible children, noted low rates of vision screening, and recommended that states begin to “develop education and incentives for providers to encourage complete medical screenings.”32