Survey Methodology – Telephone

All secrets, pros and cons of CATI methodology.

It’s the acronym of Computer Assisted Telephone Interviewing and it’s the telephone data collection. According to research dimensions, CATI methodology requires one or more telephone operators and a CATI survey software. The standard is a call center of 20-50 interviewers but it’s quite frequent to find even smaller reality.

How does CATI methodology work?

The interviewer makes a phone call to the number that is displayed on the screen. If the respondent wants to join the survey, the interviewer follows a script on the screen selecting the answers. The CATI survey tool will automatically proceed to the next question following the logic path. At the end of the questionnaire the interviewer will display a new respondent to call.

The system will manage contacts according to rules set by the administrators. For example, contacts with a busy line will be displayed again after 15 minutes. If a contact answers the call but he’s not available for the interview, the interviewer can also schedule an appointment so that the CATI software will automatically display that contact again at the date and time scheduled.

How is the call made?

Each interviewer needs a standard phone or a soft phone. In both cases, the interviewer can call clicking on the number displayed on the screen. If the line is busy, the interviewer can call a new respondent that will be automatically displayed by the software.

Time spent on call attempts can be crucial for survey costs. A solution called “Predictive Dialing” can solve this issue. With Predictive Dialing, the dialer automatically manages all calls and forwards only contacts that answer the phone.

Predictive Dialing is a feature that saves a lot of time maximizing interviewers performance.

Manual calls vs. Predictive dialing.

Work with predictive dialing.

What are outbound and inbound calls?

Everything described above is happening when the call center makes the calls.

Outbound. Some specific surveys may require a different method to allow respondents to reach the call center.

Inbound. When using Inbound, the dialer forwards the call to the first interviewer available. The interviewer can take the call and start the interview after he searched and identified the respondent in the software database.

You can also set the survey as mixed mode. This outbound-inbound mode is usually used to manage calls that the call center gets after an attempt of call. It’s in fact really frequent that contacts call back the number to know who called them. Mixed mode allows to retrieve these calls optimizing the redemption of the survey.

Scheme of the outbound-inbound flow.


It’s quite obvious that CATI methodology has high maintenance costs. The CATI tool represents just a small portion of the cost: you have to consider costs related to the interviewers, call traffic and the initial investment on stations and software.
Despite that, CATI methodology (along with CAPI) is still considered to be the most reliable and accurate mode.

Working with telephone surveys you’ll face different requirements: for some surveys you’ll need all the interviewers you have, for some others you may need half of them. Find a software provider that has license flexibility to optimize the investment!

IdSurvey – leading software for CATI, CAWI e CAPI – offers scalable solutions to earn on the initial investment just paying for real use of the software. No initial cost, also ideal for small organizations to start working with CATI with minimum costs. Cloud dialer solutions, advantageous VoIP rates and soft phones (rather than standard phones) will make Computer Assisted Telephone Interviewing method much more convenient.


We’ve just gone through CATI main characteristics highlighting high maintenance costs, higher than other methodologies. Why to use it then? You have a lot of advantages you’ll hardly get with other methodologies. The presence of a real person – that acts like a mediator between the questionnaire and the respondent – has huge benefits: the respondent can understand questions better, a lot of don’t know/don’t answer can be avoided and, last but not least, the drop out rate is much lower. CATI surveys can basically reach the entire population, something that is still impossible to do with CAWI. Let’s see a quick recap of CATI pros and cons.

Survey flow.


  • Accurate answers
  • Reliable information on respondents
  • Almost the entire population can be reached
  • You can get an accurate sample management
  • Stable redemption
  • Timing can be easily calculated
  • Out of quota interviews can be avoided
  • Full control on the survey progress
  • Real time feedback
  • The presence of the interviewer discourages interview dropout
  • Interviews can be longer as the drop out rate is lower
  • Perfect for customer satisfation
  • Good for sensitive topic
  • The agent can help in questionnaire comprehension
  • Discourage the don’t know/don’t answer


  • High costs for telephone interviewers
  • Call traffic to buy
  • PC stations
  • Costs for the dialer, software and hardware
  • The number of interviewers is directly proportional to interviews completed per day