The unique characteristic of postal administration is that the researcher has no contact with the respondent except for a cover letter he/she has written to accompany the questionnaire. In addition, mailed questionnaires are often in competition for the addressee's attention with various sorts of circulars, catalogues, and junk mail also received through mail, and the two factors together largely explain why the return rate of such surveys is often well below 30%. Such a low return rate, of course, undermines the reliability of the sample (cf. Section 3.1.3) and therefore if we decide to conduct a survey by mail we need to adopt a number of special strategies that have been found to increase the respondents' willingness to complete and return the questionnaire.
Was this article helpful?