Figure 1.

Adult Strabismus Questionnaire 20 (AS-20) response ordering for (A) 5-response self-perception subscale (representative item #1), (B) 5-response interaction subscale (representative item #5), (C) 5-response reading function subscale (representative item #12), (D) 5-response general function subscale (representative items #11), and (E) 4-response general function subscale. Response categories were properly oriented and distributed for all items in the self-perception subscale (A), interaction subscale (B), and reading function subscale (C). Using 5 response options for the general function subscale, it was evident that the “rarely” response was underutilized (D). When the “rarely” response option was combined with the “never” response option in the general function subscale, response options were properly oriented and distributed (E). A, always; O, often; S, sometimes; R, rarely; N, never; N/R, never/rarely.