title: Age- and gender-specific nomograms for single and dual post-void residual urine in healthy children.
abstract: OBJECTIVE
  To establish the first age- and gender-specific nomograms for single and two consecutive tests for post-void residual urine (PVR).
  
  
  METHODS
  Healthy children aged 4-12 years were enrolled for two sets of uroflowmetry and PVR. The first PVR and the lower value of the two consecutive PVRs of each child with a voided volume ≥50 ml were included for construction of Single- and Dual-PVR nomograms. Children with possible urinary tract infection or lower urinary tract dysfunctions were excluded.
  
  
  CONCLUSIONS
  Totally, 1,128 children (583 boys and 545 girls) with a mean age of 7.7 ± 2.2 years were eligible for analysis. The 95th percentile of Single-PVR for all children was 27.2 ml, or 19.2% of bladder capacity (BC), while that for Dual-PVR were 11.2 ml or 6.0% of BC, respectively. Multivariate studies showed that PVR was positively associated with BC, negatively associated with age, higher in boys than girls, and higher in abnormal uroflow patterns. For children aged ≤6 years, a single PVR >30 ml or >21% BC, or repetitive PVR >20 ml or >10% BC can be regarded as elevated. For children aged ≥7 years, a single PVR >20 ml or 15% BC, or repetitive PVR >10 ml or 6% BC can be redefined as elevated.
  
  
  CONCLUSIONS
  Age, gender, and BC should be taken into considerations at interpretation of PVR tests in children. Repeating PVR test is recommended when a single PVR is higher than the 95th percentile of age- and gender-specific PVR. Neurourol. Urodynam. 32: 1014-1018, 2013. © 2013 Wiley Periodicals, Inc.
authors.affiliation: Division of Urology, Buddhist Tzu Chi General Hospital, Taipei Branch, New Taipei, Taiwan; Medical College of Buddhist, Tzu Chi University, Hualien, Taiwan.
authors.forename: Shang-Jen
authors.initials: SJ
authors.lastname: Chang
authors.forename: I-Ni
authors.initials: IN
authors.lastname: Chiang
authors.forename: Cheng-Hsing
authors.initials: CH
authors.lastname: Hsieh
authors.forename: Chia-Da
authors.initials: CD
authors.lastname: Lin
authors.forename: Stephen Shei-Dei
authors.initials: SS
authors.lastname: Yang
mesh_terms: D000367:Age Factors; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D049451:Nomograms; D011237:Predictive Value of Tests; D012016:Reference Values; D015203:Reproducibility of Results; D012737:Sex Factors; D001743:Urinary Bladder / Q000502:physiology*; D014554:Urination; D014563:Urodynamics
keywords: children; lower urinary tract dysfunction; nomogram; post-void residual urine; urinary tract infection