Enclosing a pen reduced time to response to questionnaire mailings

Abstract

Objectives: To assess the effectiveness of including a pen in postal questionnaires on response rate, necessity of reminders, time to response, and completeness of response to the primary outcome question (POQ).

Study design and setting: A two-arm randomized controlled trial (RCT) embedded within the screening of older women for prevention of fracture trial (SCOOP). Women, aged 70-75 years, were randomized to receive a pen with their questionnaire (n = 3,826) or to receive the questionnaire alone (n = 3,829). The results were combined with another embedded RCT in a meta-analysis.

Results: A response rate of 92.4% was observed in the pen group compared with 91.3% in the control group (odds ratio [OR] = 1.16; 95% confidence interval [CI]: 0.98, 1.37; P = 0.08). There was a difference in reminders required (OR = 0.88; 95% CI: 0.79, 0.98; P = 0.02), time to response (hazard ratio = 1.06; 95% CI: 1.01, 1.11; P = 0.01) and some difference in the completeness of response to the POQ (OR = 1.18; 95% CI: 1.00, 1.39; P = 0.05). The pooled OR from the meta-analysis for response rate was 1.21 (95% CI: 1.05, 1.39; P = 0.01).

Conclusion: Inclusion of a pen with postal questionnaires potentially has a positive impact on response rates and the number of reminders required. There may be some reduction in time to response. Studies of different participant groups are needed to test the effectiveness over more diverse populations.

Keywords: Embedded trial; Incentive; Pen; Postal questionnaire; Randomized controlled trial; Response rate.