Publication

The Contact Lens Impact on Quality of Life (CLIQ) questionnaire: development and validation

Pesudovs, Konrad
Garamendi, Estibaliz
Publication Date
2009-06-02
End of Embargo
Supervisor
Rights
Peer-Reviewed
Yes
Open Access status
closedAccess
Accepted for publication
Institution
Department
Awarded
Embargo end date
Additional title
Abstract
PURPOSE. To develop and validate a questionnaire for the measurement of the impact of contact lenses on quality of life (QoL): The Contact Lens Impact on Quality of Life (CLIQ) Questionnaire. METHODS. The questionnaire was developed and validated using conventional methods and Rasch analysis to assure content validity, repeatability, construct validity, and low respondent burden. Item identification and selection (647 items) were performed with an extensive literature review, professional advice, and lay focus groups. Item reduction used focus groups and data obtained from 161 subjects completing a 90-item pilot questionnaire. Validity and reliability, from data of 128 additional subjects, were assessed using Rasch analysis, intraclass correlation coefficient, and Bland-Altman limits of agreement. RESULTS. A 28-item CLIQ Questionnaire was developed and shown to have good validity and reliability by Rasch analysis statistics: real person separation, 2.02; model person separation, 2.17; reliability, 0.80; root mean square measurement error, 2.73; mean square ± SD infit, 1.01 ± 0.18; outfit, 1.01 ± 0.19. The items (mean score, 49.8 ± 4.9) were well targeted to the subjects (mean score, 51.2 ± 6.2) with a mean difference of 1.35 (scale range, 0-100) units. Test-retest intraclass correlation coefficient (0.86) and coefficient of repeatability (±8.00 units) demonstrated good repeatability. CONCLUSIONS. Rasch analysis and standard psychometric analyses demonstrated that the 28-item CLIQ Questionnaire is a valid and reliable measure of QoL in contact lens wearers. A scoring algorithm is provided for CLIQ Questionnaire users to convert raw scores into the Rasch analysis-derived linear person measures.
Version
No full-text in the repository
Citation
Pesudovs K, Garamendi E and Elliott DB (2006) The Contact Lens Impact on Quality of Life (CLIQ) questionnaire: development and validation. Investigative Ophthalmology and Visual Science. 47(7): 2789-2796.
Link to publisher’s version
Link to published version
Link to Version of Record
Type
Article
Qualification name
Notes