Effects of various population groups and of distribution and return methods on the return of questionnaires and the quality of answers in large-scale travel surveys.

As part of a large scale travel survey in Austria, various target groups of transportation mode users were questioned by means of a standardised survey form. Various methods of distribution and return of the questionnaire were also used. Analysis of the results showed great differences in the response rate, the answering rate for individual questions and in the quality of answers to individual questions (error rate). target groups included urban and rural residents, domestic and foreign visitors, and road transport drivers from within and outside the area surveyed (domestic and foreign). distribution and return of the questionnaires was through the post, by personal delivery and collection, by distribution at count points and in public transport vehicles. The results showed that response rate diminished with increasing distance of the place of residence from the area surveyed. This non-response effect must not be neglected in projections. Inquiry through the post proved more effective both in terms of response rate and of costs. Response is greatly dependent on feelings about privacy of personal data. Certain questions, seeking too much detail, make excessive demands on the persons questioned and have a negative effect on response and the quality of answers. (Author/publisher) for the covering abstract of the conference see IRRD 286978.