BACKGROUND: The validity of the results of mailed surveys is often threatened by nonresponse bias, which is made more likely when response rates are low. However, the effectiveness and cost-effectiveness of several strategies to increase response rates are uncertain. OBJECTIVES: To assess three strategies to increase response rates to mailed physician surveys: including a 10 dollars versus a 5 dollars cash incentive in the initial mailing, including a mint candy or not, and using a large versus small outgoing envelope. RESEARCH DESIGN AND SUBJECTS: Using a 2 x 2 x 2 factorial design, a randomized trial of these strategies was conducted in a survey of 1200 physicians randomly selected from the American Medical Association's Master File. RESULTS: Including a 10 dollars incentive yielded a significantly higher response rate (60.5% vs. 52.8%) (P = 0.009). The mailing and incentive costs per completed response were 12.24 dollars (95% CI, 11.75 dollars, 13.64 dollars) in the 5 dollars group and 18.48 dollars (95% CI, 17.77 dollars, 20.69 dollars) in the 10 dollars group. Each additional response obtained in the 10 dollars group came at an incremental cost of 61.26 dollars (95% CI, 36.98 dollars, 200.80 dollars). Neither inclusion of a mint nor use of a large envelope influenced the response rate. CONCLUSIONS: Investigators may increase response rates by including more money in the initial questionnaire packet, but there may be diminishing returns to serial increments in incentives greater than 5 dollars. Including smaller incentives in more questionnaires may maximize total responses.
RCT Entities:
BACKGROUND: The validity of the results of mailed surveys is often threatened by nonresponse bias, which is made more likely when response rates are low. However, the effectiveness and cost-effectiveness of several strategies to increase response rates are uncertain. OBJECTIVES: To assess three strategies to increase response rates to mailed physician surveys: including a 10 dollars versus a 5 dollars cash incentive in the initial mailing, including a mint candy or not, and using a large versus small outgoing envelope. RESEARCH DESIGN AND SUBJECTS: Using a 2 x 2 x 2 factorial design, a randomized trial of these strategies was conducted in a survey of 1200 physicians randomly selected from the American Medical Association's Master File. RESULTS: Including a 10 dollars incentive yielded a significantly higher response rate (60.5% vs. 52.8%) (P = 0.009). The mailing and incentive costs per completed response were 12.24 dollars (95% CI, 11.75 dollars, 13.64 dollars) in the 5 dollars group and 18.48 dollars (95% CI, 17.77 dollars, 20.69 dollars) in the 10 dollars group. Each additional response obtained in the 10 dollars group came at an incremental cost of 61.26 dollars (95% CI, 36.98 dollars, 200.80 dollars). Neither inclusion of a mint nor use of a large envelope influenced the response rate. CONCLUSIONS: Investigators may increase response rates by including more money in the initial questionnaire packet, but there may be diminishing returns to serial increments in incentives greater than 5 dollars. Including smaller incentives in more questionnaires may maximize total responses.
Authors: Scott D Halpern; Rachel Kohn; Aaron Dornbrand-Lo; Thomas Metkus; David A Asch; Kevin G Volpp Journal: Health Serv Res Date: 2011-04-14 Impact factor: 3.402
Authors: Ellen Funkhouser; Kavya Vellala; Camille Baltuck; Rita Cacciato; Emily Durand; Deborah McEdward; Ellen Sowell; Sarah E Theisen; Gregg H Gilbert Journal: Eval Health Prof Date: 2016-01-10 Impact factor: 2.651
Authors: Melissa A Clark; Anthony Roman; Michelle L Rogers; Denise A Tyler; Vincent Mor Journal: Eval Health Prof Date: 2014-02-04 Impact factor: 2.651