Construct validity of a questionnaire to measure the type of fluid intake and type of urinary incontinence.

OBJECTIVE

To determine the reproducibility and construct validity of the Questionnaire Based Voiding Diary (QVD) for measuring the type and volume of fluid intake and the type of urinary incontinence.

METHODS

250 women completed the QVD, a 48-hour bladder diary and underwent complete urogynecologic evaluation to determine a final clinical diagnosis. The questionnaire was re-administered after a 2-week period with no change in treatment, and 2-3 months later following treatment of urinary symptoms.

RESULTS

The reproducibility of the fluid intake, output, fluid intake behavior and urinary symptom subscales of the QVD was 0.68-0.92. Correlation of the fluid intake scale of the QVD with the 48-hour voiding diary for determining the type and volume of fluid intake was high (r = 0.65-0.83, P < 0.01). High correlations were noted between the fluid intake behavior scale and urinary frequency (r = 0.82, P < .01), urgency (r = 0.77, P < .01) and urge incontinence (r = 0.71, P < .01). The median total fluid intake and mean urinary symptom score was significantly lower in responders (2074 mL, 10.2 ± 3.3) than non-responders (2347 mL, 18.5 ± 4.6). As compared to the final clinical diagnosis, the sensitivity, specificity and positive likelihood ratio of the QVD for the diagnosis of predominant stress urinary incontinence are 86%, 66% and 2.6 and for predominant urge incontinence 82%, 79% and 4.0 respectively.

CONCLUSION

The QVD provides clinically meaningful information on the type and volume of fluid intake and the type of urinary incontinence at the initial office visit.