Shazia Hussain & Louise-Anne McNutt
A study's response rate is an important gauge for the quality of data collection. The response rate, in its most basic form, refers to the proportion of people eligible for a study who actually enroll and participate. In fact, despite the name, the response rate is a proportion rather than a rate. Although the concept is simple, the computation of response rates can be complex, and the use of multiple formulas diminishes the ability to compare studies by degree of nonresponse. Any comparison of response rates between studies requires knowledge of the study designs, sampling frames, modes of study recruitment, and formulas for computing response rates. The American Association for Public Opinion Research (AAPOR) has attempted to standardize response rates for surveys conducted by mail or random-digit dialing by offering guidance on different computation methods. For example, calculating response rates for cases in a case-control study are reasonably straightforward because ...