Improved imputation of non-responses to mailback questionnaires.
Poor response rates, perhaps as low as 10 to 30 per cent, certainly bring into question the validity of any survey suffering such a malady. Repeated mailouts are capable of providing information on those persons who are resistant to responding. If one is willing to assume an exponential drop-off in response rates, then imputation is possible for the entire group of non-responders. Furthermore, a second exponential drop-off in favourable (or non-favourable) responses to particular items within the questionnaire leads to closed form estimates of population parameters and their associated standard errors. Three or more mailouts also provide a test of validity of the model assumed.
Drane
J W
JW
Epidemiology and Biostatistics Department, University of South Carolina School of Public Health, Columbia 29208.
Richter
D
D
Stoskopf
C
C
D015982:Bias; D006801:Humans; D015233:Models, Statistical; D010349:Patient Compliance; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*