Convenience voids: an important new factor in urinary frequency volume chart analysis.
OBJECTIVE
We assessed the impact of convenience voids (CVs) on urinary frequency volume chart (FVC) analysis.


METHODS
A total of 53 healthy volunteers completed a FVC for 1 week, highlighting as CVs samples when there was no sensation of bladder fullness, but rather a social reason to pass urine instead.


RESULTS
Of the volunteers 72% had at least 1 CV during the week. Removing the CVs from analysis resulted in an increase of 17 ml in average mean individual voided volume from 308 to 325 ml (p <0.001). The average mean interval between voids increased by 11 minutes from 4 hours 34 minutes to 4 hours 45 minutes (p <0.001).


CONCLUSIONS
Convenience voids have a small but significant effect on parameters analyzed on FVCs. They should be considered for inclusion in the FVCs used in research when changes in voided volume are being investigated.
Darling
Richard
R
Department of Urology, Blackburn Royal Infirmary, Blackburn, Lancashire, United Kingdom.
Neilson
Donald
D
D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011996:Records; D012016:Reference Values; D014554:Urination; D014556:Urine