Few randomized trials in preterm birth prevention meet predefined usefulness criteria

Objectives: We operationalized a research usefulness tool identified through literature searches and consensus and examined if randomized controlled trials (RCTs) addressing preterm birth prevention met predefined criteria for usefulness. Study Design and Setting: The usefulness tool included eight criteria combining 13 items. RCTs were evaluated for compliance with each item by multiple assessors (reviewer agreement 95–98%). Proportions of compliances with 95% confidence interval (CI) were calculated and change over time was assessed using ≧ 2010 as a cutoff. Results: Among 347 selected RCTs, published within 56 preterm birth Cochrane reviews, only 36 (10%, 95% CI = 7–14%) met more than half of the usefulness criteria. Compared to trials before 2010, recent trials used composite or surrogate (less informative) outcomes more often (13% vs. 25%, relative risk 1.91, 95% CI = 1.21–3.00). Only 16 trials reflected real practice (pragmatism) in design (5%, 95% CI = 3–7%), with no improvements over time. No trials reported involvement of mothers to reflect patients’ research priorities and outcomes selection. Recent trials were more transparent. Conclusion: Few preterm birth prevention RCTs met more than half of the usefulness criteria but most of usefulness criteria are improving after 2010. Use of informative outcomes, patient centeredness, pragmatism and transparency should be key targets for future research planning.