Mail surveys: obsolescent model or valuable instrument in general practice research?

Area of Science:

• Medical Research Methodology
• General Practice
• Survey Design

Background:

• Mail surveys in general practice face challenges due to low response rates.
• Costly methods like financial incentives are often required to improve participation.
• Alternative, less expensive strategies for enhancing survey response rates are needed.

Purpose of the Study:

• To determine if a good response rate is achievable in general practice mail surveys without financial incentives.
• To assess the effect of repeated follow-ups on survey results.
• To investigate cost-effective survey designs for general practitioners.

Main Methods:

• A mail survey on drug interactions was conducted among 2000 general practitioners in Germany.
• A four-stage design with two reminders was employed, excluding financial incentives.
• Response rates and the time course of response were recorded; results were compared using statistical tests.

Main Results:

• A response rate of 60.8% was achieved without financial incentives.
• The second reminder, including a questionnaire copy, was more effective than the first postcard reminder.
• Differences between early and late respondents were significant for only two questions, with minimal impact on cumulative results.

Conclusions:

• Good response rates are attainable in general practitioner surveys through meticulous planning and implementation, even without financial incentives.
• Assessing the impact of reminders on survey results early is crucial to detect potential non-response bias.
• A final reminder with a questionnaire copy can yield similar estimates to extensive follow-up procedures if no bias is detected.