Raymond Chu

Validity of the convergence insufficiency symptom survey: a confirmatory study.

Purpose. The objectives of the present study were to evaluate whether investigator bias influenced the Convergence Insufficiency Symptom Survey (CISS) scores of children with normal binocular vision (NBV) in our original validation study, reevaluate the usefulness of the cutoff score of 16, and reexamine the validity of the CISS. Methods. Six clinical sites participating in the Convergence Insufficiency Treatment Trial (CITT) enrolled 46 children 9 to <18 years with NBV. Examiners masked to the child’s binocular vision status administered the CISS. The mean CISS score was compared with that from the children with NBV in the original, unmasked CISS study and also to that of the 221 symptomatic convergence insufficiency (CI) children enrolled in the CITT. Results. The mean (±standard deviation) CISS score for 46 subjects with NBV was 10.4 (±8.1). This was comparable with our prior unmasked NBV study (mean = 8.1 (±6.2); p = 0.11) but was significantly different from that of the CITT CI group (mean = 29.8 ± 9.0; p < 0.001). Eighty-three percent of these NBV subjects scored <16 on the CISS, which is not statistically different from the 87.5% found in the original unmasked study (p = 0.49). Conclusions. Examiner bias did not affect the CISS scores for subjects with NBV in our prior study. The CISS continues to be a valid instrument for quantifying symptoms in 9 to <18-year-old children. These results also confirm the validity of a cut-point of ≥16 in distinguishing children with symptomatic CI from those with NBV.

Evaluating the burden of amblyopia treatment from the parent and child’s perspective

PURPOSE To evaluate the psychometric properties of the original Parent and new Child Amblyopia Treatment Index (ATI), questionnaires that assess the burden of amblyopia treatment in children and families, and to compare scores between children treated with atropine or patching. METHODS Parent ATI and Child ATI were administered to 233 children 7 to <13 years old and their parents as part of a randomized trial comparing patching and atropine for amblyopia treatment. For each ATI version, construct validity was assessed using factor analysis; internal consistency reliability was assessed using Cronbachs alpha. Data from the Parent ATI and Child ATI were correlated and scores for each version were compared between treatment groups. RESULTS We analyzed the 3 subscales found in prior Parent ATI studies in younger children and confirmed subscales for adverse effects and treatment compliance, but not for social stigma, in both parent and child versions. Overall and subscale scores on the Parent ATI and Child ATI were moderately to well correlated except for the social stigma subscale. For both the Parent ATI and the Child ATI, children treated with atropine had better scores than those treated with patching, both overall and on treatment compliance and social stigma subscales (all p values ≤ 0.01). CONCLUSIONS When used for children 7 to <13 years old, the Parent ATI and Child ATI have similar factor structures to each other and to the Parent ATI for children 3 to <7 years old. Atropine treatment was found to have less negative impact than patching.

The Effect of an On-Site Vision Examination on Adherence to Vision Screening Recommendations

Vision screenings are intended to efficiently identify students with possible visual impairment and initiate a referral for diagnosis and treatment. In many cases, at-risk students do not access the recommended care or experience delays in receiving care. The purpose of this article is to report the effect on adherence to vision screening recommendations by providing the eye examination at the students’ school and at no cost. Of the 1,306 students screened, 382 (29.2%) were identified with possible visual impairment. Parental consent for examination was obtained for 198 (51.8%) students. Our vision screening and examination program yielded similar adherence to follow-up as stand-alone vision screening programs. Future program considerations should address perceptual barriers that may be contributing to parental nonadherence to vision screening recommendations.

Feasibility of a clinical trial of vision therapy for treatment of amblyopia.

Purpose We conducted a pilot randomized clinical trial of office-based active vision therapy for the treatment of childhood amblyopia to determine the feasibility of conducting a full-scale randomized clinical trial. Methods A training and certification program and manual of procedures were developed to certify therapists to administer a standardized vision therapy program in ophthalmology and optometry offices consisting of weekly visits for 16 weeks. Nineteen children, aged 7 to less than 13 years, with amblyopia (20/40–20/100) were randomly assigned to receive either 2 hours of daily patching with active vision therapy or 2 hours of daily patching with placebo vision therapy. Results Therapists in diverse practice settings were successfully trained and certified to perform standardized vision therapy in strict adherence with protocol. Subjects completed 85% of required weekly in-office vision therapy visits. Eligibility criteria based on age, visual acuity, and stereoacuity, designed to identify children able to complete a standardized vision therapy program and judged likely to benefit from this treatment, led to a high proportion of screened subjects being judged ineligible, resulting in insufficient recruitment. There were difficulties in retrieving adherence data for the computerized home therapy procedures. Conclusions This study demonstrated that a 16-week treatment trial of vision therapy was feasible with respect to maintaining protocol adherence; however, recruitment under the proposed eligibility criteria, necessitated by the standardized approach to vision therapy, was not successful. A randomized clinical trial of in-office vision therapy for the treatment of amblyopia would require broadening of the eligibility criteria and improved methods to gather objective data regarding the home therapy. A more flexible approach that customizes vision therapy based on subject age, visual acuity, and stereopsis might be required to allow enrollment of a broader group of subjects.