Disqualification Logic

Often market researchers run surveys with samples that may not be qualified for the study. In order to figure out which respondents to keep inside of the survey, the researcher asks a few background questions, and if the person responds with the right choices, they qualify for the survey. If they respond with other choices, they don’t qualify.

For example: Q: Which of these is your favorite product? a) Product A b) Product B c) Product C d) Product D If you only want to know information from those that select product B as their favorite product, than anyone that selects A, C, or D is redirected to a screen that thanks them for their time and informs them that they do not qualify for the current study. Once at that screen, however, many researchers make a questionable choice. They include the option of going back, and selecting a different answer, which in turn lets them qualify for the survey.

This may not be the best idea.

When you ask qualification questions, you only want those that are going to be qualified. If it wasn’t important to you to select those that provide you with an honest answer in the qualification questions, then you should not have chosen the qualification questions at all. Once you allow your sample to go back and take the question over again, you’re giving them permission to lie about their answer, and give you data that isn’t indicative of your original goal.

If you have specific qualifications for your research, you should stick with them. However, perhaps you are concerned that your sample is selecting an answer haphazardly, without strong feelings between the products, thereby disqualifying themselves despite technically being qualified for the survey. If this is your concern, you can always add another answer: e) I like more than one of the above products equally.

Then you can direct them to another page, and on the next page have them select which products they like equally. If yours is included, allow them to qualify for the survey. Yet regardless how you choose to handle it, it’s not necessarily a good idea to allow users to go back and answer survey qualification questions again.

All you do is risk collecting data on someone that is not answering genuinely, while the gain – getting a larger sample – is minimized by the lack of faith you can have in that person’s data.