How to perform questionnaire studies
Questionnaires are often used for data collection in epidemiological studies and are a relatively inexpensive way to collect information for research purposes. The aim of a questionnaire is to generalize replies from a small sample to a larger population. If people do not reply to the questionnaires (so called “non-responders”), the research results will tend to be less accurate. Non-responders reduce the effective sample size and can introduce bias. Thus, when performing questionnaires a crucial point is to obtain a sufficiently high response rate. Some ways to obtain that are presented here. First, the odds of response are almost doubled if the respondents are paid for their participation. However, some more inexpensive factors can be easily adjusted to attract the respondents’ interest.