Table 3 Results of interrupted time-series analysis evaluating differences between groups for 11 quality indicators and one clinical outcome (perineal incision) before and after multifaceted audit and feedback intervention

Indicator 1 - Spontaneous vaginal birth

 Preintervention slope (per month)

0.97 (0.93 to 1.02)

0.212

 Change in level after intervention

0.87 (0.65 to 1.02)

0.366

 Change in slope (per month) after intervention

1.08 (1.00 to 1.16)

0.037^a

Indicator 2 - Labour induction

 Preintervention slope (per month)

1.02 (0.85 to 1.22)

0.864

 Change in level after intervention

2.01 (0.81 to 4.94)

0.131

 Change in slope (per month) after intervention

0.82 (0.62 to 1.08)

0.158

Indicator 3 – No perineal tear and no perineorrhaphy

 Preintervention slope (per month)

1.09 (0.95 to 1.25)

0.225

 Change in level after intervention

0.65 (0.30 to 1.40)

0.272

 Change in slope (per month) after intervention

1.00 (0.82 to 1.23)

0.974

Indicator 4 - Second degree perineal laceration

 Preintervention slope (per month)

1.01 (0.96 to 1.07)

0.574

 Change in level after intervention

1.01 (0.77 to 1.33)

0.919

 Change in slope (per month) after intervention

0.98 (0.90 to 1.06)

0.549

Indicator 5 - Postpartum haemorrhage more than 500 grams within 2 hours of birth

 Preintervention slope (per month)

0.95 (0.82 to 1.01)

0.475

 Change in level after intervention

1.13 (0.47 to 2.73)

0.784

 Change in slope (per month) after intervention

1.01 (0.79 to 1.28)

0.965

Indicator 6 - Uterotonics for the prevention of postpartum haemorrhage

 Preintervention slope (per month)

1.01 (0.97 to 1.04)

0.629

 Change in level after intervention

0.86 (0.67 to 1.10)

0.225

 Change in slope (per month) after intervention

1.00 (0.94 to 1.07)

0.902

Indicator 7 - Admission to paediatrics department within a week after birth

 Preintervention slope (per month)

0.90 (0.78 to 1.05)

0.175

 Change in level after intervention

0.92 (0.36 to 2.34)

0.859

 Change in slope (per month) after intervention

1.13 (0.86 to 1.44)

0.329

Indicator 8 - Feeding only breast milk at the time of discharge from the hospital

 Preintervention slope (per month)

1.01 (0.92 to 1.11)

0.818

 Change in level after intervention

1.02 (0.58 to 1.79)

0.951

 Change in slope (per month) after intervention

0.97 (0.83 to 1.13)

0.699

Indicator 9 - Formula supplementation without medical rationale during hospitalization

 Preintervention slope (per month)

1.01 (0.85 to 1.19)

0.911

 Change in level after intervention

0.89 (0.34 to 2.29)

0.802

 Change in slope (per month) after intervention

1.07 (0.84 to 1.36)

0.586

Indicator 10 - Women switched to receive care provided primarily by obstetricians

 Preintervention slope (per month)

1.10 (0.95 to 1.26)

0.203

 Change in level after intervention

0.90 (0.36 to 2.28)

0.831

 Change in slope (per month) after intervention

0.80 (0.62 to 1.04)

0.096

Indicator 11 - Feeding only breast milk at the time of the health examination for children of 1 month of age

 Preintervention slope (per month)

1.03 (0.96 to 1.11)

0.383

 Change in level after intervention

1.14 (0.79 to 1.64)

0.479

 Change in slope (per month) after intervention

0.93 (0.83 to 1.03)

0.159

Indicator 12 - Perineal incision

 Preintervention slope (per month)

1.09 (0.95 to 1.25)

0.229

 Change in level after intervention

0.69 (0.29 to 1.64)

0.404

 Change in slope (per month) after intervention

0.92 (0.71 to 1.19)

0.533