Block 1977

Methods	Type of study: RCT Method of treatment allocation: computer‐generated randomisation sequence. Coded drug boxes were provided. Stratification: none stated Placebo: yes, normal saline Sample size calculation: no Intention‐to‐treat analyses: no Losses to follow‐up: yes, 14 (10%) women delivered elsewhere and were lost to follow‐up. 6 (4%) women were excluded from analyses as they failed to complete the protocol. Funding: Schering Corporation, Kenilworth, New Jersey, USA; and The Upjohn Company, Kalamazoo, Michigan, USA
Participants	Location: Department of Gynecology and Obstetrics at the University of Oklahoma College of Medicine, Oklahoma City, Oklahoma, USA Timeframe: not stated in manuscript, the study is coded as 1970s for the review Eligibility criteria: women with preterm labour and PROM Gestational age range: not stated Exclusion criteria: not stated Total recruited: the number randomised to each group not stated. Data are available on 114 infants; 60 infants in the treatment arm and 54 infants in the control arm
Interventions	12 mg betamethasone IM repeated after 24 h if delivery had not occurred Control group received 1 mL normal saline IM repeated after 24 h if delivery had not occurred. If there was evidence of progressive cervical dilatation an alcohol infusion was given in order to attempt to delay delivery for at least 48 h. In women with PROM delivery was induced if serial white blood cell counts or temperatures became elevated regardless of time elapsed since drug administration.
Outcomes	Fetal/neonatal outcomes reported (fetal death, neonatal death, RDS, need for mechanical ventilation/CPAP)
Notes	This study included a third arm (125 mg methylprednisolone IM repeated after 24 h if delivery had not occurred). The data for the review report the betamethasone and control arms only. Overall data were available for 150 living infants, of whom 128 were preterm. Further information was requested from the study authors but there was no reply.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Computer generated randomisation sequence."
Allocation concealment (selection bias)	Low risk	"Consecutively numbered boxes containing randomly selected study drug or placebo."
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Clinicians were never aware of the contents of the coded box. Placeob was saline so it is likely that participants were blinded.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Blinding of outcome assessors was not described.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	14 (10%) women delivered elsewhere and were lost to follow‐up. 6 (4%) women were excluded from analyses as they failed to complete the protocol (1 in the betamethasone group, 2 in the methylprednisolone group, and 3 in the control group).
Selective reporting (reporting bias)	Low risk	Study protocol not available, but appears to report on all pre‐specified outcomes.
Other bias	Unclear risk	Insufficient information to assess if other sources of bias exist.