Web-based contraception decision support tool and women’s decisional conflict: a cluster randomised trial in Spain

Background The choice of a contraceptive method is a complex decision in which decisional conflict can occur, which can lead to poor adherence and unplanned pregnancies. The objective was to assess whether a web-based Decision Support Tool (DST) reduced decisional conflict compared with usual contraceptive counselling. Methods A parallel, controlled cluster randomised clinical trial was carried out in 43 clinical contraceptive counselling units in Spain between 2019 and 2021. Seventy-one professionals were randomly assigned to intervention group or control group and recruited a sample of 895 women. Participants in the intervention group (IG, n = 478) received professional counselling supported by the DST, after brief training in its use, while those in the control group (CG, n = 417) received the same professional counselling without the tool (usual care). Decisional conflict, a prespecified secondary outcome of the trial, was measured with O’Connor’s 16-item Decisional Conflict Scale. Results Decisional conflict was low in both groups; only 1.9% of participants in the intervention group and 1.7% in the control group had DCS scores above 37.5. After accounting for the clustering effect by professional and adjusting for baseline covariates, no statistically significant differences in total decisional conflict were observed between the groups (adjusted mean difference: 2.2 points; 95% CI: −1.9 to 6.3; p = 0.297), nor in any of the subscales (all p ≥ 0.13). Variability between professionals was considerable (ICC = 0.37 for the total score; between 0.24 and 0.34 for the subscales), and the results remained unchanged in a three-level sensitivity analysis. Conclusions In this cluster-randomised trial, we found no evidence that the decision support tool (DST) reduced decisional conflict among women receiving contraceptive counselling; after accounting for the clustering effect by provider, decisional conflict did not differ significantly between groups and was generally low. A substantial portion of the residual variability in decisional conflict was attributable to the providers offering the counselling rather than to the tool itself. Therefore, the DST may be more useful as a complement to professional counselling than as a substitute for it. Trial registration ISRCTN58279944. Registered 15 April 2019 (prospectively registered).