NON-RESPONSE BIASNESS

Non-response is a major challenge facing studies using survey as a method of data collection.
Barriball and While (1999) recommend that researchers should conduct a non-response bias analysis regardless of how high or how low the response rate is achieved.
The most familiar understanding of non-response is the degree to which a researcher does not succeed in obtaining the responses from all potential respondents included in the sample.
By using Mann Whitney-U test proposed by Weis and Heide (1993) potential for non-response biasness were computed by considering the dissimilarity between early and late respondents with respect to the means of all the variables.