Authors should have used standardised questionnaire

EDITOR—Møller et al did not describe in detail the questionnaire that they used in their longitudinal study of lower urinary tract symptoms in women,1 but it seems to have been based on two different instruments. 2 3 The Bristol female lower urinary tract symptoms questionnaire uses a five point scale for reporting symptoms.3 Respondents can reply “never,” “occasionally,” “sometimes,” “most of the time,” or “all of the time” when asked whether they have a particular symptom; when asked about frequency they can reply “never,” “once or less a week,” “2-3 times a week,” “once a day,” or “several times a day.”

This raises the issue of reproducibility when the questionnaire is completed on more than one occasion. Reproducibility of our instrument was good when a test-retest analysis was performed with a two week interval, there being no apparent change in the underlying condition during that time; 78% of symptom questions were answered identically on both occasions, with no responses changing by more than two categories. The instrument used by Møller et al is reported to have fair to excellent reproducibility, but details …