Table 2.

Risk Factors for UTI

Risk FactorRelative RiskPrevalence, %Sample Size*AuthorDateSource
Gender
Male (<1 y)00193Roberts et al19835031  (13)
Male (<1 y)0.32.5945Hoberman et al19935062  (12)
Male (3–8 mo)0.11 100Ginsburg and McCracken19821022  (4)
Male (0–1 y)0.734.2 1177Jodal19873048  (66)
Male (1–2 y)0.21.7 1177Jodal19873048  (66)
Male (0–10 y)0.231.9 1177Jodal19873048  (66)
Male (1–12 mo)2.87.4 112Elzouki et al19851028  (93)
Male (1–5 y)0.553.5 112Elzouki et al19851028  (93)
Weighted average, Male (<1 y)0.483.3
Weighted average, Male (>1 y)0.231.9
Female (<1 y)7.4193Roberts et al19835031  (13)
Female (<1 y)3.58.8945Hoberman et al19935062  (12)
Female (3–8 mo)109.1 100Ginsburg and McCracken19821022  (4)
Female (0–1 y)1.45.8 1177Jodal19873048  (66)
Female (1–2 y)58.3 1177Jodal19873048  (66)
Female (0–10 y)4.38.1 1177Jodal19873048  (66)
Female (1–12 mo)0.362.6 112Elzouki et al19801028  (93)
Female (1–5 y)1.86.5 112Elzouki et al19801028  (93)
Weighted average, Female (<1 y)2.66.5
Weighted average, Female (>1 y)4.78.1
Circumcision0.050.3 2502Wiswell et al19855042  (26)
00 2019Wiswell and Roscelli19864021  (27)
0.10.6 496Wiswell and Hachey1993no # (28)
0.070.4 112Ginsburg and McCracken19821022  (4)
Weighted average0.040.21
  • * Different studies report different outcomes. Thus, the data cannot be pooled. The sample size refers to the number of subjects in the entire study. The weighted average is weighted by this number.

  • These studies examined only children with UTI. In these studies, relative risk is estimated by OR as P(male‖UTI)/P(female‖UTI). The prevalence is derived by assuming an overall prevalence of 5% for both genders and a 50% prevalence of males in the population, using the formula,P(UTI‖male) = P(male‖UTI) ·P(UTI)/P(male). A comparable formula is used for females.

  • Only the probability of circumcision given UTI [P(circ‖UTI)] is reported. Relative risk is estimated by OR, P(circ‖UTI)/P(no circ‖UTI). Estimates of prevalence of UTI given circumcision [P(UTI‖circ)] are calculated by assuming the previous probability of UTI regardless of circumcision status [P(UTI)] is 5%, and the probability of circumcision (among males) is 70%. Prevalences are calculated using these estimates and Bayes's formula: P(UTI‖circ) =P(circ‖UTI) ·P(UTI)/P(circ).