The Effects of Source Credibility and Message Variation on Mail Survey Response Behaviour

Grounded on persuasive communications theory, the impact of source credibility and message variation on response behaviour towards a mail survey on a sample of the general public are examined. An experimental design comprising three levels (high, medium and low) of these variables is employed. Source credibility and the interaction of message variation (i.e. usefulness of the study) and source credibility have a significant impact on response rate. Overemphasising the usefulness of a study is found to be counterproductive. For sources that are arguably average or lower in credibility, a strongly worded message (in terms of usefulness) was less effective than more modest objectives.