An empirical examination of the relationship between nonresponse rate and nonresponse bias

Abstract

The dramatic decline in survey response rates over the past three decades raises significant concerns about the possibility of bias in survey results. Current theory emphasizes that it is the relationship between response propensity and variables of interest that determines the extent of the bias, and that a low response rate in itself does not necessarily imply a high level of bias. This assertion is supported by a number of studies which have shown that response rate alone is a fairly poor predictor of nonresponse bias. However, most of these studies suffer from methodological features that in some way compromise their attempts to isolate the relationship between response rate and bias. This paper describes the results of a pair of studies which allow for a near-ideal examination of this relationship. The results support the conclusions of prior research, showing that even achieved samples with response rates as low as 10 percent may produce highly accurate estimates in certain cases.