Abstract
Abstract: :
Purpose: We have developed a new diplopia scoring system using a cervical range of motion (CROM) device, which standardizes head positions for the assessment. We have also developed a brief diplopia questionnaire addressing the frequency and positions of gaze of a patient’s diplopia. We have previously reported excellent agreement with the standard diplopia field performed on the Goldmann perimeter. In the current study, we investigated the test–retest reliability and responsiveness of the new measures. Methods: 42 adult patients with strabismus and diplopia were prospectively enrolled at two sites (27 in the test–retest study and 15 in the responsiveness study). Diagnoses included cranial nerve palsies, thyroid eye disease, supranuclear palsies and ocular myasthenia gravis. In the test–retest study, the CROM diplopia exam scores were obtained by two independent examiners at the same visit. In the responsiveness study, the CROM diplopia exam score and diplopia questionnaire score were obtained pre– and post–intervention (surgery or oral prednisone, depending on the condition) 1 to 15 months later (median 2 months). All scores were scaled from 0 to 100, and we compared the scores using intraclass correlation coefficients (ICC) or paired Wilcoxon tests. Results: Inter–tester reliability of the CROM diplopia exam score was excellent (ICC = 0.87, 95% CI: 0.74 to 0.94, with a median difference in scores of 0 (quartiles 0 to 8). In the responsiveness study, the baseline CROM diplopia scores ranged from 12 to 100 and diplopia questionnaire scores ranged from 20 to 100. Post–intervention scores were significantly lower than baseline (p=0.0003 for CROM and p=0.0001 for the questionnaire), with a median post–intervention improvement of 48 for the CROM diplopia score (quartiles 12 to 68) and 36 for the diplopia questionnaire (quartiles 20 to 52). Conclusions: Our new CROM diplopia exam score and new diplopia questionnaire score are valid, reliable and responsive measures of diplopia severity. The tests are easy to administer and require minimal equipment. Our new methods for quantifying diplopia may prove to be valuable outcome measures for future clinical trials.
Keywords: clinical (human) or epidemiologic studies: systems/equipment/techniques • strabismus: diagnosis and detection • quality of life