Survey Methods to Optimize Response Rate in the National Dental-PBRN

Objectives: To quantify the increase in response rate associated with successive survey methods in a questionnaire completed by general dentists (GDs).
Methods: All GD members of the National Dental Practice-Based Research Network (www.NationalDentalPBRN.org) who reported on their Enrollment Questionnaire that they do at least some root canal treatment (RCT) were sent a postal invitation describing the study. Following this introductory letter, up to six recruitment steps were followed to obtain a completed questionnaire: initial email; 2 email reminders at 2-week intervals; a third email reminder with postal mailing of paper questionnaire; a second postal mailing of paper questionnaire; Regional Coordinators’ follow-up by telephone.
Results: Of the 1876 GDs invited, 23 were deemed ineligible before beginning the questionnaire and 139 were determined ineligible after completing the questionnaire (3 no longer a GD; 136 do not do at least one RCT each month), leaving 1714 eligible dentists; 23 were ‘active’ refusals and 194 were non-respondents. Thus, 1497 responded (87.3%), of whom 1491 (87.0%) partially completed the survey, and 1488 (86.8%) completed the entire survey. Among the 1491, participation at each step was 35% with initial email, 15% with second email, 7% with third email, 11% with fourth email/first paper, 15% with second paper, and 16% with Regional Coordinator follow-up. Overall, 25% completed on paper. Participation rates were higher for large group practices than other practice settings, and for non-Hispanic White and Asian GDs compared to other races/ethnicities. Completion on paper [vs. online] was higher among owners of private practices, older practitioners and those who had postgraduate GD training.
Conclusions: Using multiple methods of recruitment resulted in a high participation rate (87%); each step and method produced incremental increases. Support: U19-DE-22516.