The use of Visual Analog Scale in urogynecologic research: a psychometric evaluation

OBJECTIVE: The purpose of this study was to assess the validity of Visual Analog Scales in urogynecologic research. STUDY DESIGN: In phase I, 35 women completed short forms of the urogenital distress inventory, incontinence impact questionnaire, and Beck depression inventory fast screen using the Likert-type scale and Visual Analog Scale formats. Reliability was estimated with Spearman's correlations and Cronbach's alpha; construct validity was assessed with the use of factor analyses. In phase II, 101 women were recruited for the test-retest reliability assessment of the Visual Analog Scale formats of the urogenital distress inventory and incontinence impact questionnaire short forms. Reproducibility was analyzed with intraclass correlations. RESULTS: In phase I, correlations between the Likert-type scale and the Visual Analog Scale were good: urogenital distress inventory (0.748), incontinence impact questionnaire (0.787), and Beck depression inventory fast screen (0.852; P <.05). In phase II, intraclass correlations were 0.898 and 0.938 for the urogenital distress inventory and incontinence impact questionnaire scores, respectively ( P <.001). CONCLUSION: The Visual Analog Scale is a simple, reliable, and reproducible method for the assessment of quality of life in urogynecologic research.