An intention-to-treat analysis was conducted. Baseline data were compared descriptively between treatment groups. Perinatal and neonatal deaths were excluded from the analyses of measures of neonatal morbidity. Fisher's exact test was used to compare binary outcomes and Student's t-test to compare continuous variables that were normally distributed. Because only women with an ECV procedure were assessed for pain during the procedure, we used linear regression to calculate adjusted between-treatment comparisons of pain by controlling for baseline variables where there was either imbalance between treatment groups or where the variable correlated with pain scores on the first ECV. A P-value of <0.05 (two-sided) indicated statistical significance for the primary and secondary outcome and <0.01 (two-sided) indicated statistical significance for other outcomes. Relative risks and 95% CI were used to report the effects of the intervention on each outcome and risk difference (RD) was calculated for the primary and secondary outcomes. Subgroup analyses were undertaken using logistic regression analyses to test for interactions between baseline characteristics (parity [0 versus ≥1], type of breech [frank versus non-frank], gestational age at randomisation [33–34 weeks versus 35 weeks of gestation], and the national perinatal mortality rate of the country [≤20/1000 versus >20/1000]) and treatment group for the primary and secondary outcomes. The statistical software sas version 9.1 (SAS Institute, Cary, NC, USA) was used for the analyses.
In keeping with recommendations for presentation of findings in the context of prior research and existing knowledge,14
we undertook meta-analyses of the primary and secondary outcome data from this trial and the Early ECV Pilot Trial, the only previous study to compare early and delayed timing of ECV. We pooled the summary data for the primary and secondary outcomes of caesarean section and preterm birth before 37 weeks of gestation using a Mantel–Haenszel fixed effects model to calculate the RR, weighted RD and 95% CIs of harm or untoward outcome, using Review
(RevMan Version 5.0 Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2008) Using data from both trials, we calculated the number needed to treat to prevent one caesarean section and the number needed to treat to harm for preterm birth.
Steering committee. EK Hutton, J Barrett, GD Carson, MF Delisle, M Dunn, S Edwards, A Fernandez, A Gafni, ME Hannah, S Hewson, R Natale, A Ohlsson, SJ Ross, AR Willan, R Windrim, JK Pollard, I Schweitzer, G Sylvestre, P Turtle.
Data Safety Monitoring Board. Bracken M, Crowley P, Donner A, Duley L, Ehrenkranz R.
Collaborators. Argentina—M Curioni, R Abalos Gorostiaga (Hospital Ramon Carrillo, Santiago del Estero); C Becker, PA Elizabeth, L Errandonea, M Palermo, CA Ramos, M Trabucco, D Montes Varela (Hospital Posadas, Buenos Aires); MS Bertin, JL Castaldi (Hospital Penna, Bahia Blanca); M Mohedano de Duhalde (Hospital Avellaneda, Tucuman); C Becker (Hospital Durand, Buenos Aires); A Messina (Hospital Alvarez, Buenos Aires); Australia—J Baumgartner, G Kovacs, B Malcolm, JR Neil (Box Hill Hospital, Box Hill); K Mahomed (Ipswich Hospital, Ipswich); A Child, B DeVries, H Phipps, A Welsh (Royal Prince Alfred Hospital, Sydney); GK Davis, L Roberts, NP Watts (St George Hospital, Sydney); M Cybulski, D Gibson, S Tucker (Toowoomba Base Hospital, Toowoomba); I McCahon, P Sheehan, M Umstad (University of Melbourne Dept. of Obsetrics & Gynecology, The Royal Women's Hospital, Carlton); J Milligan, J Morris, K Rickard (Royal North Shore Hospital, St. Leonards); G Gardener, S Jenkins-Manning (Mater Mothers’ Hospital, Brisbane); C Boniface, M Edmondson, D Watson (Townsville Hospital, Townsville); A Green (Ipswich Hospital, Ipswich); Brazil—A Ayub (ISCMPA-Maternidade Mario Totta, Porto Alegre); Canada—MF Delisle, S Soanes, (Children's & Women's Health Centre of BC, Vancouver); A Jordan, R Windrim (Mount Sinai Hospital, Toronto); C Fanning, B Parish (IWK Health Centre, Halifax); R Natale, MA Watson (St Joseph's Health Centre, London); D Reid, P Scheufler (Trillium Health Centre, Mississauga); AM Malott, A Reitsma (Hamilton Health Sciences Corporation McMaster Site, Hamilton); KA Haslauer, M Lipp (Lion's Gate Hospital, Vancouver); D Farquharson, K Gray (Royal Columbian Hospital, New Westminster); N Demianczuk, E Penttinen (Royal Alexandra Hospital, Edmonton); E Herer, K McLean (Sunnybrook Health Sciences Centre, Toronto); F Aghajafari, S Williams (Regina General Hospital, Regina); C Moravac, M Yudin (St Michael's Hospital, Toronto); J Pollard, L Miller (Calgary Health Region—Foothills Hospital, Calgary); RB Anderson (St Paul's Hospital, Vancouver); M Good, MC Walker (The Ottawa Hospital—General Campus, Ottawa); R Kulkarni, R Scarfone (North Bay General Hospital, North Bay); C Cameron, T Peel (Markham Stouffville Hospital, Markham); Chile—J Carrillo, A Cruces, Y Gonzalez (Hospital Padre Hurtado, Santiago); J Figueroa Poblete, L Lama Hormazabal, J Saez, (Hospital Clinico San Borja Arriaran, Santiago); E Oyarzun, A Rioseco (Pontificia Universidad Católica de Chile, Santiago); S Illanes, C Kottmann (Hospital Parroquial de San Bernardo, San Bernardo); M Parra, S Quezada, L Quiroz (Hospital Clinico Universidad de Chile JJ Aguirre, Santiago); Denmark—L Hvidman, IM Mogensen, A Mouritzen (Aarhus University Hospital, Aarhus); B Ostberg (Gentofte University Hospital, Hellerup); Egypt—SNM Abdel-Samad, T Al-Hussaini, I El-Nashar (Assiut University Hospital, Assiut); Estonia—F Kirss, K Rull, E Ustav, P Vaas (Tartu University Hospital-Women's Clinic, Tartu); Germany—V Brink-Spalink, K Weizsaecker (CUB-Virchow Klinikum, Berlin); Hungary—T Major, R Poka (University of Debrecen, Debrecen); Ireland—S Daly, (Coombe Women's Hospital, Dublin); Israel—H Kaneti, D Rosen, B Schachter (Meir Medical Center, Kfar-Saba); B Chayen, L Harel (Ma'ayney HaYeshua Medical Center, Bnei Brak); Z Hiaeb, G Malinger (Edith Wolfson Medical Center, Holon); D Dukler, E Lunenfeld (Soroka Medical Center, Beer Sheva); Jordan—L AlFaris, M El-Zibdeh (Islamic Hospital, Amman); Poland—I Domzalska-Popadiuk, P Kobiela, Z Pankrac, J Preis, K Preis, M Swiatkowska-Freund (Medical University of Gdansk, Gdansk); Portugal—J Cravo (Hospital Distrital de Faro, Faro); South Africa—AM Theron, GB Theron (Stellenbosch University, Tygerberg); HS Cronje, JM du Plessis (University of Free State, Bloemfontein); Spain—M Munoz (Hospital Clinic-University of Barcelona, Barcelona); Sultanate of Oman—G Khan, S Khan (Khoula Hospital, Muscat); the Netherlands—S Goossens, M Pieters, FJME Roumen (Atrium Medical Center, Heerlen); F ten Cate, M Pieters, F Smits (Academisch Ziekenhuis Maastricht, Maastricht); M Heres, E Krabbendam (Sint Lucas Andreas Ziekenhuis, Amsterdam); United Kingdom—R Airey, D Farrar, DJ Tuffnell (Bradford Royal Infirmary, Bradford); V Heyes, C Melvin, C Schram (Royal Blackburn Hospital, Blackburn); A Galimberti, P Stewart (Royal Hallamshire Hospital, Sheffield); J Cresswell (Chesterfield Royal Hospital, Chesterfield); C McCormick (Nottingham City Hospital, Nottingham); United States of America—J Andrews, D Fleener (University of Iowa Hospitals and Clinics, Iowa City); D Coonrod, BF Jimenez (Maricopa Medical Center, Phoenix); S Brown, A Gregg (University of South Carolina, Columbia); C Pitchford, D Seubert (New York University School of Medicine, New York).