Uroflowmetry in children--is it necessary to repeat the study in a single patient?

Uroflowmetry, as the only non-invasive urodynamic means of assessing the function of the lower urinary tract is widely used in children. A possible psychological influence on the results is the reason why uroflowmetry is often repeated in the same patient.

The investigation was conducted to compare parameters of repeated uroflowmetry in a single child with the results of single uroflowmetry performed in a group of children. The goal of the study was to evaluate the efficacy of a single uroflow procedure in children.

A single uroflowmetric study was performed in 44 children aged from 9 - 11 years (mean 10 yrs). Out of the group one child was chosen who had 32 successive uroflow attempts. The range and average values of the uroflowmetric parameters were compared in both groups. Pearson's correlation coefficient was used for calculation and for a comparison of the uroflowmetric parameters of both groups (significance level p < 0.05).

Average values of the voided volume, maximal and average flow were lower in the 32 attempts of a single child than in the control group (44 attempts). The values of the Pearson's correlation coefficient were ranged from 0.2 to 0.4 for flow/voided volume ratio and from 0.4 to 0.8 for flow time/voided volume ratio in both groups. There were no differences between the values in both groups apart from flow time/voided volume correlation (significance level p < 0.05).

Repetition of uroflowmetric study does not seem to improve the efficacy of the modality in assessing voiding function in children.