NICE (2013) states that men with bothersome lower urinary tract symptoms should complete a urinary frequency-volume chart as part of their initial assessment. They provide information on: daytime frequency, nocturia, 24-hour frequency, 24-hour production, polyuria, nocturnal urine volume, nocturnal polyuria and maximum voided volume (Abrams et al. 2002). Frequency-volume charts can help to distinguish between nocturnal polyuria and detrusor overactivity by assessing the volume of urine voided (NICE, 2013).