There was a significant but small reduction in the rate of cesarean delivery from the preintervention period to the postintervention period in the intervention group as compared with the control group ( change , @ % to @ % in the intervention group and @ % to @ % in the control group ; odds ratio for incremental change over time , adjusted for hospital and patient characteristics , @ ; @ % confidence interval -LSB- CI -RSB- , @ to @ ; P = @ ; adjusted risk difference , -@ % ; @ % CI , -@ to -@ ) .