Effectiveness of follow-up techniques with nonresponders in mail surveys

One hundred thirty-six mail questionnaire studies which surveyed at least 70 pharmacy practitioners, pharmacy school alumni or pharmacy school-based educators in the U.S. or Canada from 1985 to August 1995 were reviewed to assess the relationships between different follow-up techniques and survey return rates. The scope of each study was categorized as being national, regional/provincewide/statewide, single school (alums) or multiple school (faculty). Least squares multiple regression, weighted for survey sample size, was used to assess the association between return rate and use of prenotification, reminders, second and subsequent mailings, telephone follow-up and other follow-up methods. Although the effectiveness of these techniques varied as a function of a study's scope, and not all techniques were used in every survey, only a second mailing of the survey instrument to nonresponders was significantly associated with higher return rates across all respondent categories.