With the advent of software designed to control telephone surveys and enter data in one step, telephone interviewing became an even more cost-effective means of collecting information. Our custom-designed CATI software gives us the flexibility to ask the most complex questions in a simple straightforward manner.

• It is possible to draw large geographically dispersed samples using this methodology.
• Random digit dialing means that even unlisted numbers can be reached. By setting callback rules (meaning every number is tried a minimum number of times, usually three), the researcher can adhere to proper sampling methods.
• As questionnaires are programmed into a computer, changes to the questionnaire are easy to make. More complex questions and skip patterns can be utilized since the computer keeps track of all answers.
• Data entry costs are eliminated, since respondents’ answers go directly into a database.
• Large numbers of interviewers can be assigned to a study, resulting in rapid completion of even large studies.
• Questionnaires can be pretested, modified and the full study launched the next day.

• Length of interview limits the amount of information that can be gathered. The optimum length of a telephone interview is less than 15 minutes, with the maximum amount of time respondents will stay on the phone about 30 minutes (this requires considerable effort on the part of the Interviewer, and possibly an incentive.)
• Surveys on exhibits ( e.g. advertising/promotional materials) can not be easily performed over the telephone, and are impossible with Random Digit Dialing.
• It can be difficult to deal with complex questions and scales over the telephone.