TABLE 2.
Hazard of Early-Term Nonindicated Delivery, Overall and by Mode of Delivery Initiation (Cesarean versus Induction), Controlling for Patient and Hospital Factors (N=7,296,363)
| Early-term nonindicated delivery (any) HR (95% CI)a | Early-term nonindicated cesarean HR (95% CI)a | Early-term nonindicated labor induction HR (95% CI)a | |
|---|---|---|---|
| Maternal age | |||
| <20 | 1.00 (0.98, 1.01) | 1.20 (1.18, 1.23) | 0.77 (0.75, 0.79) |
| 20–24 | 0.96 (0.95, 0.97) | 1.00 (0.99, 1.02) | 0.91 (0.90, 0.93) |
| 25–29 | Reference | Reference | Reference |
| 30–34 | 1.07 (1.06, 1.08) | 1.09 (1.07, 1.1) | 1.06 (1.04, 1.07) |
| 35+ | 1.30 (1.29, 1.32) | 1.51 (1.49, 1.54) | 1.11 (1.09, 1.13) |
| Race | |||
| White Non-Hispanic | Reference | Reference | Reference |
| Black Non-Hispanic | 0.96 (0.94, 0.98) | 1.29 (1.27, 1.32) | 0.65 (0.64, 0.67) |
| Asian/Pacific Islander Non-Hispanic | 0.79 (0.78, 0.81) | 1.02 (1, 1.04) | 0.58 (0.57, 0.6) |
| Hispanic | 0.76 (0.75, 0.77) | 0.94 (0.93, 0.96) | 0.59 (0.58, 0.6) |
| Education | |||
| No high school | 0.79 (0.77, 0.8) | 0.85 (0.83, 0.87) | 0.71 (0.69, 0.73) |
| Some high school | 0.93 (0.91, 0.94) | 0.93 (0.91, 0.95) | 0.92 (0.9, 0.94) |
| High school diploma/GED | Reference | Reference | Reference |
| At least some college | 1.05 (1.04, 1.06) | 1.08 (1.07, 1.1) | 1.01 (1, 1.03) |
| Insurance status | |||
| Medicaid | Reference | Reference | Reference |
| Private FFSb | 1.06 (1.04, 1.07) | 1.02 (1, 1.05) | 1.1 (1.07, 1.12) |
| Private HMOc | 1.02 (1.01, 1.04) | 0.95 (0.93, 0.96) | 1.13 (1.11, 1.15) |
| Uninsured | 0.85 (0.81, 0.89) | 0.8 (0.75, 0.86) | 0.91 (0.85, 0.97) |
| Hospital volume | |||
| Very low (<250) | 1.19 (1.15, 1.24) | 1.28 (1.22, 1.35) | 1.12 (1.07, 1.18) |
| Low (250–1000) | 1.04 (1.03, 1.05) | 0.99 (0.98, 1.01) | 1.09 (1.07, 1.11) |
| Medium (1000–5000) | Reference | Reference | Reference |
| High (5000+) | 1.02 (1.00, 1.03) | 1.06 (1.04, 1.08) | 0.96 (0.94, 0.98) |
| Geographic location | |||
| Urban | Reference | Reference | Reference |
| Rural | 1.03 (1.01, 1.05) | 0.99 (0.96, 1.03) | 1.06 (1.03, 1.09) |
| Hospital teaching status | |||
| Teaching | Reference | Reference | Reference |
| Nonteaching | 1.08 (1.07, 1.10) | 0.98 (0.96, 1.00) | 1.23 (1.20, 1.25) |
| Year | |||
| 1995 | Reference | Reference | Reference |
| 1996 | 1.03 (1.00, 1.06) | 0.95 (0.92, 0.99) | 1.10(1.06, 1.14) |
| 1997 | 1.12 (1.09, 1.15) | 1.03 (0.99, 1.07) | 1.21 (1.16, 1.25) |
| 1998 | 1.23 (1.20, 1.26) | 1.13 (1.09, 1.17) | 1.32 (1.27, 1.37) |
| 1999 | 1.36 (1.32, 1.39) | 1.32 (1.27, 1.37) | 1.39 (1.34, 1.44) |
| 2000 | 1.35 (1.32, 1.39) | 1.37 (1.32, 1.42) | 1.34 (1.29, 1.39) |
| 2001 | 1.46 (1.42, 1.49) | 1.59 (1.53, 1.65) | 1.34 (1.29, 1.39) |
| 2002 | 1.53 (1.49, 1.57) | 1.72 (1.66, 1.78) | 1.36 (1.32, 1.41) |
| 2003 | 1.64 (1.60, 1.68) | 1.90 (1.84, 1.97) | 1.04 (1.35, 1.45) |
| 2004 | 1.76 (1.72, 1.81) | 2.07 (2.00, 2.14) | 1.49 (1.44, 1.55) |
| 2005 | 1.97 (1.92, 2.02) | 2.31 (2.23, 2.39) | 1.67 (1.62, 1.73) |
| 2006 | 2.03 (1.98, 2.08) | 2.37 (2.29, 2.45) | 1.75 (1.69, 1.81) |
| 2007 | 2.02 (1.97, 2.06) | 2.36 (2.28, 2.44) | 1.72 (1.66, 1.78) |
| 2008 | 1.97 (1.92, 2.02) | 2.37 (2.29, 2.45) | 1.62 (1.56, 1.68) |
| 2009 | 1.86 (1.81, 1.90) | 2.29 (2.21, 2.37) | 1.47 (1.42, 1.52) |
Notes: Models also included cephalo-pelvic disproportion, state fixed effects, and adjusted standard errors to account for hospital-level clustering. Missing values constitute <2% of the sample and are separately controlled but not reported.
a
HR, hazard ratio; CI, confidence interval
b
FFS, fee-for-service
c
HMO, health maintenance organization