A Comparison of Mail and Face-to-Face Survey Methods: New Zealand Health Professionals

This study compares response rates obtained by two methods of data collection, mail survey and face-to-face interview, with health professionals. The study goes further by attempting to compare the quantity and quality of response derived from each data collection method as well as examining two potential sources of bias (acquiescence and social desirability) in the face-to-face interview data. A two page questionnaire was sent to 109 general surgeons and 34 district nurses. One reminder with another copy of the questionnaire was sent to non-respondents two weeks later. Forty-nine general surgeons and 39 district nurses were interviewed in person. General surgeons were just as likely to respond to either method of data collection; district nurses were more likely to respond to the face-to-face survey. Furthermore, the presence of an interviewer did not necessarily yield greater amounts of information, nor did our results show any conclusive difference in the quality of responses. While evidence of both acquiescence (primarily from hasty completion) and social desirability bias were detected in our results for general surgeons, neither was sufficiently large to provide conclusive evidence of an impact. We believe that our findings give some reassurance to researchers in the health industry that mail surveys of health professionals can produce results similar to those obtained by face-to-face interviews