Women in an infertility survey responded more by mail but preferred a choice: randomized controlled trial.

OBJECTIVES: To evaluate three modes of questionnaire completion (online, mail, and telephone) and a choice group for a questionnaire survey with a sensitive topic. STUDY DESIGN AND SETTING: A randomized trial of alternative completion methods (online, paper [mail], telephonic interview, and a choice of the three modes) for a survey about fertility problems embedded within a population-based cross-sectional survey of reproduction among women living in England and Wales. RESULTS: From an initial cohort of 21,036 women who were sent a screening questionnaire, 4,559 responded. A total of 699 women reported fertility problems, of whom 593 (85%) agreed to participate. A total of 521 (75%) of the 699 women then completed the survey. Compared with the "mail" arm, those allocated to telephonic interview were less likely to agree to participate initially (odds ratio [OR], 0.41; 95% confidence interval [CI]: 0.22, 0.74) but were ultimately more likely to complete the questionnaire (OR, 2.20; 95% CI: 1.01, 4.80). Overall, those allocated to the choice arm were most likely to go through to completion (80% vs. 77% mail, 72% telephone, and 68% online groups). In the choice arm, women showed a clear preference for mail (59% vs. 37% choosing online and 3% telephonic response). CONCLUSIONS: Online surveys are a viable alternative to mailed questionnaires but were not as popular as mail in this study population. Response can possibly be increased by offering women a choice of response modes.