Study	Reason for exclusion
Beazley 2001	Study design: randomised prospective trial. Intervention: weekly contact with a nurse versus routine care. Participants: 218 women at high risk of preterm birth Outcomes: preterm birth before 37 weeks’ gestation and spontaneous preterm birth before 37 weeks’ gestation Published in abstract form only. Not clear how many patients were in control and intervention groups therefore analysis not possible. No decrease in the incidence of preterm birth or spontaneous preterm birth in the intervention group (43% vs 41%, 35% vs 30% respectively)
Collaborative Group 1993	Study design: multi-centre randomised controlled trial. Intervention: preterm labour prevention programme with additional visits, education about the signs of preterm labour and cervical assessment at routine visits vs routine care. Participants: 2395 women considered at high risk of preterm delivery. Outcomes: spontaneous preterm birth by 36 and 37 completed weeks with and without PPROM, very low birthweight (< 1500 g at birth), low birthweight (< 2500 g at birth). Women with multiple pregnancies included in all the analyses. Creasy publication of data froma cohort of the women included in the Collaborative Group on Preterm Birth Prevention publication
Goldenberg 1990	Study design: multi-centre randomised controlled trial. Intervention: preterm labour prevention programme with weekly visits, education about the signs of pretermlabour and cervical assessment at routine visits vs routine care. Control women seen in different clinics from intervention patients. Participants: 678 women considered at high risk of preterm delivery. Outcomes: spontaneous preterm birth at less than 37 completed weeks, very low birthweight (< 1500 g at birth), low birthweight (1500-2499 g at birth), spontaneous preterm PROM rate. Women with multiple pregnancies included in all the analyses
Pittsburgh 1989	Study design: randomised controlled trial. Intervention: preterm labour prevention programme with weekly visits, education about the signs of preterm labour and cervical assessment at each visit vs routine care Participants: 831 women considered at high risk of preterm delivery out of 5457 women screened. Outcomes: spontaneous preterm birth at less than 37 completed weeks. Women with multiple pregnancies included in all the analyses

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