Callbacks

Callbacks are a survey disposition that is specific to telephone surveys. They are a common temporary survey disposition because fewer than half of all completed interviews occur on the first dialing of a case. Callbacks happen for a number of reasons. For example, an interviewer might dial a telephone number in the sampling pool and be told that the designated respondent is not available to complete the interview at the time of the call. In other cases, the interviewer might reach the designated respondent but learn that he or she would prefer to complete the interview at another time. A callback might also occur if an interviewer dials a telephone number and reaches an answering machine or a voicemail service. Callbacks are considered a positive outcome because they usually indicate that the household or designated respondent is eligible and that an interview is likely to be completed with the respondent if the interviewer is able to reach him or her at a good time. Cases coded with the callback disposition usually are considered eligible cases in calculating survey response rates because the interviewer has been able to determine that the household or designated respondent meets the qualifications set by the survey researcher for completing the interview.

Callbacks can occur for multiple reasons, and as a result the callback disposition often is further categorized into a general callback disposition and a specific callback disposition. In a general callback, the interviewer learns that the designated respondent is not available at the time of the call but does not learn anything that would help him or her determine the best time to reach the designated respondent. In other cases coded with a general callback disposition, the interviewer may obtain some information about when to next make a call attempt on the case (such as "evenings only" or "before 2:30 p.m.") but is not able to make an appointment to contact the designated respondent at a definite day or time. In a specific callback, however, the interviewer learns enough to set a definite day and time for the next call attempt (such as, "appointment set for 2:30 p.m. tomorrow"). Aside from learning the day and time for subsequent call attempts, interviewers also should attempt to obtain other information that might increase the chances of converting the callback into a completed interview. This information might include the name and/or gender of the designated respondent, or any other information that might help the interviewer reach the designated respondent on subsequent call attempts.

Because cases coded with the callback disposition are eligible and continue to be processed in the sampling pool, information learned during previous call attempts about when to contact the designated respondent can be used to better target subsequent call attempts by the interviewer. For a specific callback, additional call attempts should occur at the appointment time set by the respondent; additional call attempts on a general callback in which little is known might be made at a variety of other days and times in order to increase the chances of reaching the designated respondent and/or to learn more about how to target additional call attempts.

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