Back checks are done primarily to check the authenticity of the interview. Hence it is very important that the back checks are done within 48 hours of the interview, else there are chances that the respondent may have lapse of memory with respect to the exact answers given. It may not be practically possible for the MRUC members to adhere to the above; hence the back-checks should be done and looked at objectively.

Back checks also serve the purpose of collecting correct information, if some information filled in by the interviewer is found to be incorrect.

Before starting back checks it is advisable to go through the completed questionnaires and identify areas, which look problematic either because the responses are not coded properly, or the responses to various questions are conflicting.