• To determine how severe the incontinence is:
• Ask how often the woman is incontinent, at what times, and during which activities.
• Ask about the use of pads or changing of clothing.
• Ask the woman whether she restricts her daily fluid intake and how often she passes urine, including at night.
• Ask the woman to keep a bladder diary for 3 days to document the amount and types of fluids drunk, individual voided volume, frequency of micturition, episodes of incontinence, and pad and clothing changes. Ask her also to record episodes of urgency.
• Ask about associated symptoms, such as daytime and night-time urinary frequency.

• Bladder diaries document fluid intake, how often urine is passed, ideally a measurement of how much urine is passed (or whether the amount passed is large or small), episodes of incontinence, and pad or clothing changes.
• The normal volume of urine passed per void is between 200 mL and 400 mL [Rogers, 2008], and the generally quoted average voiding frequency is four to eight times daily, including one void per night.

Use of pads to assess severity

• The recommendation to assess severity of incontinence by asking about the use of pads is based on expert advice in a review article [O'Neil and Gilmour, 2003].
• The National Institute for Health and Clinical Excellence (NICE) evaluated 20 studies on pad testing (14 considered the test-retest reliability of pad testing and six case series measured the test-retest reliability over 24–72 hours). NICE concluded that the evidence supporting the use of pad testing is of poor quality and contradictory, but although there is no evidence for their diagnostic value, they may be useful in evaluating the outcome of treatment [National Collaborating Centre for Women's and Children's Health, 2006].

Bladder diaries

• Bladder diaries are recommended by the National Institute for Health and Clinical Excellence (NICE).
• NICE evaluated five studies that were all case series and analysed bladder diaries kept for 1 day (one study), 3 days (one study), and 7 days (three studies). NICE concluded that bladder diaries were a reliable method of quantifying urinary frequency and incontinence and were useful for assessing the outcome of treatment. Although the optimum duration of bladder diaries was unclear from the studies, NICE recommends that they should be kept for a minimum of 3 days [National Collaborating Centre for Women's and Children's Health, 2006].
• CKS expert reviewers stated that the accepted voiding frequency was a maximum of eight times in 24 hours. A study on asymptomatic women (n = 300) in the US who kept a 24 hour log of fluid intake and volume of urine voided found that the median number of voids in 24 hours was eight and that 95% of women reported voiding fewer than 13 times in 24 hours [Fitzgerald et al, 2002].
• A Health Technology Assessment found that bladder diaries were the most cost-effective method of assessing severity compared with pad testing and validated scales [Martin et al, 2006].