Further validation of the Amblyopia Treatment Index parental questionnaire

BackgroundThe Amblyopia Treatment Index (ATI) is a parental questionnaire that has been used to assess the impact of patching or atropine treatment on the child and family in several amblyopia treatment studies. The 18-item parental questionnaire was designed with versions for treatment with patching or atropine. We pooled data across studies to further evaluate the validity of the ATI, to further assess the presence or absence of factors (subscales).MethodsA parent or guardian completed the ATI for 794 children who participated in 1 of 4 randomized clinical trials. Internal consistency reliability was assessed with Cronbach's α, and factor analysis was performed.ResultsThe ATI demonstrated high internal consistency reliability, with a Cronbach's α of 0.88 (95% CL = 0.87, 0.89). Factor analysis revealed the same 3 minimally overlapping factors found in the original validation study, which were again labeled “adverse effects,” “treatment compliance,” and “social stigma.” Two of the 18 items did not load with any factor and could reasonably be omitted from future ATI administrations.ConclusionsThe ATI is a useful instrument for assessing the impact of patching or atropine treatment on the child and family.