In survey research, response rate refers to the number of people who successfully responded to the survey v/s those in the sample. It is generally expressed in ratio or percentage terms. Let’s say that the survey was sent to 1000 people out of which 260 responded back with a complete response. The response rate ratio here is 0.26 and percentage response is 26%. Earlier it was believed that higher the response rate, better the accuracy of survey. As measure of the relationship between accuracy and non-responses of surveys is difficult and costly, there were not many rigorous studies to prove the bad effects of a low response rate until very recently. However, because of emergence of numerous statistical tools, required studies for the same have been recently carried out and most studies indicate that it is not worth it to increase the response rate frequently because of lower effect on the survey accuracy.
Response rate ratio is also used to explain the success of a direct marketing campaign. Here the response rate ratio indicates the number of people who accepted the offer. Here, higher the ratio directly indicates success of the campaign.
Response rate ratio is also used to explain success of medical procedures primarily in oncology. Response-rate ratio is a measure of efficiency of medical treatment. It is the ratio of number of medically better patients in the treatment group to the control group.