Across the 683 hospitals in the sample, the average weighted circumcision rate was 55.9%. summarizes observed male circumcision rates. When we did not control for correlated factors, routine circumcision was less common in hospitals with higher proportions of births paid for by Medicaid (36.8%), in hospitals with greater proportions of uninsured deliveries (47.3%), and in hospitals that serve a greater share of patients in the lowest quartile of the income distribution (44.4%; P<.001). Male circumcision rates were higher (72.3%) in the one third of the hospitals with the largest proportion of infants who are White (P<.001) and lower (39.0%) in the one third of the hospitals with the largest proportions of infants who are Hispanic (P<.001). Male circumcision rates were lower (36.0%) in hospitals with the largest proportions of newborns with 1-day stays (P<.001).
Neonatal male circumcision rates differed significantly across regions of the country (P<.001). Male circumcision rates averaged 77.2% in the Midwest, 68.7% in the Northeast, 59.7% in the South, and just 27.1% in the West. Bivariate analyses showed that neonatal male circumcision rates were higher in teaching hospitals (P<.001) and in hospitals located in rural areas (P=.021). However, a hospital’s circumcision rate was not significantly related to the number of beds (P=.216).
Our public policy measure also showed a significant relationship with neonatal male circumcision rates. In states whose Medicaid program covers neonatal male circumcision, rates were more than twice as high (69.6%) as in states whose Medicaid program does not pay for male circumcision (31.2%).
Regression results, presented in , show effects of each factor with control for all other predictors. The set of primary payer variables significantly predicted neonatal male circumcision rates (F=22.96; P<.001). Hospitals with higher proportions of Medicaid-covered births (P<.001) and uninsured births (P<.004) had lower circumcision rates than did hospitals with more patients covered by private insurance. However, in states in which Medicaid paid for routine neonatal circumcision, rates were significantly higher than in states in which this was not the case (P<.001). As expected, the greater the share of Medicaid-covered births in the hospital, the greater the effect of state coverage for neonatal male circumcision on the hospital’s circumcision rate.
Multiple Regression Results With Multiply Imputed Data Sets For Predictors of Male Infant Circumcision: Nationwide Inpatient Sample, 2004
Circumcision rates varied significantly by region in the regression analysis (F=16.13; P<.001). Relative to hospitals in the South, and with control for other factors, neonatal male circumcision rates were significantly lower in the West (P<.001) and the Northeast (P<.001), but not significantly different in the Midwest (P=.164). Even net of region effects, the race/ethnicity variables remained highly significant predictors of male circumcision (F=29.35; P<.001). Hospitals that had a greater proportion of Hispanic newborns relative to Whites showed significantly lower circumcision rates (P<.001), although hospitals in which African Americans accounted for a larger share of the births relative to Whites did not differ significantly.
The length-of-stay variables were also significantly related to male circumcision rates in the regression analysis (F=12.20; P<.001). Hospitals with greater proportions of very short maternity stays (P<.001) had lower circumcision rates. Hospitals with larger shares of very long stays also had lower circumcision rates (P<.001) compared with hospitals in which a greater share of the maternity stays were between 2 and 5 days.
Although they had significant bivariate relationships with neonatal male circumcision rates, rural status, hospital teaching status, and median income in the zip code of the child’s residence were not significantly associated with circumcision rates once we controlled for region and other patient characteristics. Neither hospital size (F=0.14; P=.866) nor hospital ownership (F=1.82; P=.122) was significantly associated with male circumcision rates.
Retransforming the parameter estimates in to the original scale, we can predict differences in hospital circumcision rates when varying a single factor. For example, other factors being equal, we estimated that a hospital in the Northeast would have a circumcision rate 10 percentage points lower than would a comparable hospital in the South; a comparable hospital in the West would have a male circumcision rate 15 percentage points lower than would a hospital in the South.
A hospital with 35% of newborn males having only a 1-day length of stay (which is 1 SD above the mean of 19%) would be expected to have a circumcision rate that is 6 percentage points lower than would a comparable hospital with the percentage of newborns having a 1-day length of stay at the mean. Other factors being equal, a hospital whose percentage of newborn males staying 6 days or more is 12% (mean + 1 SD), is predicted to have a circumcision rate 7 percentage points lower than is a hospital with the average proportion of length of stay of 6 days or more (4%).
The estimated impact of Medicaid coverage for routine circumcisions is substantial: given the proportions of patients with Medicaid as primary payer across observed hospitals, the model predicted that hospitals in states that cover routine circumcisions have circumcision rates averaging 24 percentage points higher than comparable hospitals in states in which Medicaid does not cover neonatal male circumcision. This overall effect is complicated by the significant interaction effects of state Medicaid coverage with the percentage of births that are Hispanic.
shows that even in states in which Medicaid pays for neonatal male circumcision, the rates of circumcision fall with increasing shares of births that are paid for by Medicaid. However, the decline in circumcision associated with a higher proportion of patients with Medicaid insurance is much steeper when Medicaid does not cover the procedure.
Predicted neonatal male circumcision rates as a function of Medicaid coverage of circumcision and the percentage of male newborns in hospital for whom Medicaid is their primary payer: Nationwide Inpatient Sample, 2004.
Further, the greater the share of Hispanic births at a hospital, the smaller the difference in male circumcision rates between states with and without Medicaid coverage of routine circumcision (P=.031), as illustrated in . These predictions, based on the regression, show that although when the proportion of Hispanic births is low there is a large differential between male circumcision rates in states with and without Medicaid coverage of neonatal male circumcision, this differential narrows when the proportion of Hispanic births is very high.
Predicted neonatal male circumcision rates as a function of Medicaid coverage of circumcision and percentage of births that are Hispanic: Nationwide Inpatient Sample, 2004.