cchang wrote:I just try to find out if the low return (2.7%) can in fact render their survey/result invalid! Anyone else out here can give advice ? Thanks Carl.
I think it is impossible to say whether the survey study is valid or invalid without knowing more about the methods and results. Even a very tiny sample % can give accurate results if it is a truly random sample, or if enough is known to be able to correct for observed biases. Also, without knowing the interpretation of the survey, it is impossible to say whether the interpretation is correct, or whether it warrants the position held by the health authority.
For more info, you might want to get a copy of this paper from a local university, or by sending a reprint request to the authors.
Title: Addressing Nonresponse Bias in Postal Surveys
Author(s): MacDonald SE, Newburn-Cook CV, Schopflocher D, et al.
Source: PUBLIC HEALTH NURSING Volume: 26 Issue: 1 Pages: 95-105 Published: JAN-FEB 2009
That paper includes references to several other relevant studies.