There were 38 studies of nurse practitioners with a total of 21,261 patients (12 randomised controlled trials, RCTs, and 26 non-randomised studies) and 15 studies of nurse midwives with a total of 7,066 patients (2 RCTs and 13 non-randomised studies).
Nurse practitioner/physician comparison studies.
Only patient compliance was assessed by randomised trials: nurse practitioners' patients scored higher than physicians' patients (ES 0.36, 95% confidence interval, CI: 0.08, 0.64, p=0.01). Randomised studies combined with studies controlling for patient severity: nurse practitioners ordered more laboratory tests than did physicians (ES 0.20, 95% CI: 0.10, 0.29, p<0.0001), their patients pathological conditions such as blood-pressure improved (ES 0.28, 95 % CI: 0.04, 0.51, p=0.01) and they received higher patient satisfaction scores (ES 0.30, 95% CI: 0.20, 0.40, p<0.0001). There were no differences in quality of care, prescribing of drugs, functional status, number of visits per patient and use of the emergency room.
Nurse midwives/physician comparison studies.
Studies controlling for patient risk: with low-risk patients, nurse midwives used significantly less analgesia (ES -0.52, 95% CI: -0.76, -0.28, p<0.0001), anesthesia (ES -0.99, 95% CI: -1.23, -0.74, p<0.0001), foetal monitoring (ES -0.37, 95% CI: -0.57, -0.16, p=0.0003), forceps delivery (ES -0.48, 95% CI: -0.63, -0.33, p<0.0001), amniotomies (ES 0.37, 95% CI: -0.61, -0.14, p=0.001) and intravenous fluids (ES -0.72, 95% CI: -0.99, -0.46, p<0.0001). Rates of Caesarean sections were equivalent but midwives' patients had significantly more spontaneous abortions than physicians' patients (ES 0.41, 95% CI: 0.27, 0.56, p<0.0001). Foetal distress and 1-minute Apgar scores were the same, midwives delivered fewer low-birth weight babies than physicians (ES -0.10, 95% CI: -0.16, -0.03, p=0.001).