Mail Surveys of Professional Populations The Effects of Monetary Gratuities on Return Rates

• Published in: The Journal of experimental education Vol. 56; no. 4; pp. 173 - 175
• Main Authors: Hopkins, Kenneth D., Hopkins, B. R., Schon, Isabel
• Format: Journal Article
• Language: English
• Published: Washington, DC Routledge 01-07-1988; Heldref Publications; Heldref
• Subjects: Advertising research; Confidence interval; Educational research; Educational sciences; Incentives; Mail Surveys; Mailings; Marketing; Methodology; Money; Opinion polls; Professional Workers; Public opinion; Questionnaires; Research design; Research Responses; Response rates; Survey research; Surveys, interviews
• ISSN: 0022-0973; 1940-0683
• DOI: 10.1080/00220973.1988.10806483

Because virtually all published research on the effect of a monetary gratuity has been in the context of public opinion polling or market research by sampling nonprofessional populations, a randomized experiment was conducted in a mail survey of 507 professional school and public librarians. A random half (Group E) had $1.00 attached as a small token of appreciation for their cooperation. The conventional questionnaire methodology was employed for Group C. In the initial mailing, the gratuity had a powerful influence on the rate of return-80% vs. 59%. Indeed, the response rate with the gratuity for the first mailing (80%) was higher than that obtained for Group C with two mailings (74%). (No gratuity was included for either group in the second mailing.) The return rate for Group E increased to 86% following the second mailing, an unusually high return rate for a mail survey even among professional populations. Even though professional populations typically have much higher response rates than the general population, a $1.00 gratuity can have a substantial effect on increasing the return rate and, consequently, can strengthen the external validity of survey findings.