Purchase this article with an account.
Stephen J. Smith, Laura Liebermann, Sarah R. Hatt, David A. Leske, Jonathan M. Holmes; Quantifying Diplopia Using a Patient-reported Outcome Questionnaire. Invest. Ophthalmol. Vis. Sci. 2011;52(14):6361.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
We have previously described a diplopia questionnaire that rates diplopia on a 3-point scale (never, sometimes, always) in specific positions of gaze. Using this questionnaire in clinical practice suggested a need for additional response categories. Specifically, patients with rare diplopia were often unable to decide between never and sometimes and patients with frequent diplopia were often able to decide between sometimes and always. We therefore tested a revised diplopia questionnaire (RDQ) adding categories of rarely and often, to yield 5 levels (never, rarely, sometimes, often, always) for each gaze position (reading, straight ahead distance, down, right, left, up, and other).
94 consecutive adult strabismus patients completed the RDQ at their office visit. In 17 (15%) of these patients, the questionnaire was completed again one week later (range 1 to 68 days) to evaluate test-retest reliability. Possible scores ranged from 0 (no diplopia) to 100 (diplopia always in all positions of gaze), weighted to straight ahead distance and reading. We evaluated the frequency of using rarely and often responses, the overall distribution of scores, and test-retest reliability by Intraclass Correlation Coefficient (ICC).
The new response options of rarely and often were used by 44 (47%) of 94 patients. Scores were distributed between 0 to 100, with 4% to 23% in each decile, indicating use of the whole range. Test-retest reliability was excellent, with an ICC of 0.92 (95% CI 0.79 to 0.97).
The Revised Diplopia Questionnaire (incorporating rarely and often response options) appears useful in quantifying diplopia and has excellent test-retest reliability. This questionnaire provides a standardized method for patients to record their symptoms of diplopia and therefore is useful in clinical practice. Additionally, the Revised Diplopia Questionnaire score provides a quantitative outcome measure for future clinical studies.
This PDF is available to Subscribers Only