How Does The Length Of An Interview Affect The Incidence Of A Study?

When it comes to collecting data and information from people, there are a variety of techniques to accomplish this task. The choice of a means to obtain the answers we seek depends on multiple circumstances. Among these we find the available budget, the methodology to be used and the profile of the respondents. However, there is another factor that must be taken into account and that largely defines the scope of a project.

The time we ask of consumers is not something that can be taken lightly. In an ideal world, we would like our research participants to have complete availability to collaborate. However, the reality is different since each of us has many more activities to do beyond being part of a market study sample. For this reason, we list some considerations about the duration of a contact in the field.

First response bias. In general terms, there is a directly proportional relationship between the duration of a conversation and this bias. The longer the interview, the greater the prevalence of this phenomenon. Although there are solutions such as rotating response batteries to reduce it, they do not eliminate it. A suggestion to minimize this situation is to design questionnaires that are intuitive, coherent and without apparent repetition of items.

Loss of participants. In some investigations, a consumer recruitment phase may be included in order to agree on an appointment that includes an established duration to cooperate in a specific activity. However, if the duration of the interview is very long and we are working with people with many responsibilities, we run the risk of losing contact due to the emergence of urgent situations or desperation from people who will ask us to finish an activity hastily.

Appropriate methodology. For quantitative studies, it is suggested to apply short interviews and for qualitative ones, longer ones. This last is a very large generalization, but it largely summarizes our experience in various research protocols. Many quantitative studies are collected through face-to-face, door-to-door, telephone or internet interviews, so the longer the duration, the lower the quality of the data collected. In qualitative studies it is possible to extend the survey due to the need to apply several open questions.

Weight in budget. Despite the advice described above, there are times when there will be no other alternative and it will be necessary to apply long interviews given the objectives of the study. In this case, it is essential to have the necessary resources to deploy the number of interviewers and incentives that ensure we meet the objectives. Otherwise, you may incur costly delays and mid-course adjustments.

How long each contact with a consumer lasts must be carefully considered to evaluate the implications it will have at all stages of a project. If survey times in the field are not realistically planned before executing the operational phase, it is possible to make errors that cannot be corrected later. On more than one occasion it will be more prudent to review other stages such as the design of the question guide to make it more viable or have elements to compromise people’s participation.

At Acertiva we put our more than twenty years of experience at your disposal to advise your market research projects. Our analysts and strategic allies in Latin America are ready to add their answers to the solution of your needs. Contact us today to find out how together we can write your next success story.



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