Questionnaire in Omnibus studies

An omnibus survey is a particular type of study on which clients buy space for their own questions. The questionnaire can therefore cover a number of different subject areas for a number of different clients. The cost of sampling and contacting these respondents is effectively shared between all of the clients, making this a cost-effective way of asking a limited number of questions of a large sample or one that is expensive to sample.

Several different topics are asked about, and the question writer will not know what has been previously covered. The first question should therefore include a bridging phrase or sentence to indicate that a change of subject is about to occur.

Omnibus surveys are normally charged by the number of questions; whether they are pre-coded or open-ended; whether they use prompts or not; and the proportion of the sample of which they are asked. To keep down the cost, question writers must decide what are the most essential questions they need to cover, in order to limit the number.

The order of the questions may also be affected by the desire to keep down the cost. For example, we may be interested in asking some ques­tions of people who have visited or considered visiting a particular resort. Normally we might ask:

Q1. SHOW CARD.

Which of the resorts on this card have you ever visited?

Q2. SHOW CARD.

And which others have you ever considered visiting?

Both questions would be asked of all respondents.

However, if the number who have visited or have considered visiting is a minority, the cost can be reduced by reversing the questions:

Q1. SHOW CARD.

Which of the following resorts have you ever considered visiting,

regardless of whether you have actually visited them?

Q2. SHOW CARD.

And which have you actually visited?

The first question is still asked of all respondents, but the second one is only asked of people who say that they have considered the resort in which we are interested. We can still classify all respondents into the three categories – visited, considered but not visited, and not considered – but, because the second question is only asked of a minority of the sample, we have saved money.

Source: Brace Ian (2018), Questionnaire Design: How to Plan, Structure and Write Survey Material for Effective Market Research, Kogan Page; 4th edition.