When a respondent starts an interview, the routing section of the interview script controls which questions the respondent sees and in which order. When the respondent clicks Next after answering the last question, the interviewing program terminates the interview and flags it as completed. For more information, see Standard end-of-interview procedure.

Not every interview that starts becomes completed. The respondent might decide to abandon the interview partway through, and just lets the browser session time out. Alternatively, they might click Stop. If a project uses quotas to balance the different types of people that take part in the survey, some interviews might have to be terminated because the respondent belongs in a group whose target has already been met. Occasionally, an interview fails because of a script error. Consider all of these scenarios when writing and testing a script, even if the solution is just to display a message before closing the interview. For more information, see Ending or stopping interviews and Dealing with off-path data.

In some cases, partially completed interviews can be restarted. Generally, the interviewing program deals with this automatically, but it might help to understand what happens behind the scenes so that you can take this into account when testing the script. For more information, see Restarting stopped interviews.

Respondents sometimes forget what answers they have given to earlier questions, or they might want to change an earlier answer. They can use one of the navigation buttons to go back to any question that they have already answered. The interviewing program rolls back the interview to that point and, depending on what changes, if any, are made, might replay the interview to follow the original path through the interview or might take a different path with new questions if this becomes necessary. If a different set of questions is asked, the old data becomes “off path” and is not normally saved, but you can specify differently if you want. For more information, see Save points, rollbacks and replays.

You can roll back interviews from the script. A typical example is where the answers to a set of numeric questions do not sum to 100%. By rolling back the interview rather than just skipping back with GoTo, you ensure that the interview state the second time the questions asked is exactly the same as when they were first asked, and that any temporary variables that might have been set are automatically reset during the rollback.

See also “Review Interviews” and “reviewing interviews” (interviewers) in the UNICOM Intelligence Interviewer - Server User's Guide.