Is it possible to increase the response rate for a mail survey by contacting the respondents before they receive the survey? A study designed to address this question compared three groups of subjects. The first received a preliminary letter about the survey, the second received a phone call, and the third received no preliminary contact. A positive response was defined as returning the survey within two weeks. The data:
Response Letter Intervention Phone Call None
Yes 25 38 52
No 23 23 58
Is there evidence to conclude that there is a difference between the different methods of intervention? Carry out an appropriate hypothesis test, filling in the information below.
A. The value of the test statistic:
B. The p-value:
C. Your decision for the hypothesis test, assuming a significance level α=0.1: