Which data collection method should I choose?
Personal interviews are still commonplace for collecting primary information for good reasons:
Better explanations. In a face-to-face interview, respondents have more time to consider their answers and the interviewer can gain a deeper understanding of the validity of a response. Sometimes interviewers need to show advertisements, logos, headlines or samples and this is plainly suited to personal situations.
Depth. It is easier to maintain the interest of respondents for a longer period of time in face-to-face interviews. Being face to face with respondents gives the interviewer more control and refusals to answer questions are less likely than over the telephone. Concern about confidentiality can be more readily satisfied than with an `anonymous' person at the end of a phone.
Greater accuracy. In a face-to-face interview respondents can look up information and products can be examined. If the interview is at a business, files of information can be referred to, or phone calls made to colleagues to confirm a point. The interviewer may be able to make a visual check to ensure that the answers are correct.
Product placements. Product placements can be sent through the post but it is usually better for them to be delivered by hand by the interviewer. Face-to-face contact with respondents permits a more thorough briefing on how to use the product. Pre-test questions can be asked, and arrangements can be made for the follow-up.
Against the advantages of face-to-face interviewing, there are a number of disadvantages:
Organisation. Face-to-face interviews are difficult to organise. If the interviews are country-wide, a national field force is required. The subject may be complex and demand a personal briefing, which is expensive to arrange when interviewers are scattered geographically.
Control. Monitoring and controlling face-to-face interviews is more difficult than with telephone interviews. Face-to-face interviews need to have a supervisor in attendance for part of the time and check-backs, by visit or post, must be organised. For the most part, however, the interviewer is working in isolation and the quality of the work has a considerable dependency on the conscientiousness of the individual.
Cost. The cost of face-to-face interviews is considerably higher than the cost of carrying out telephone interviews.
Time. Face-to-face interviews are time consuming because of the travel time between respondents. The prior commitments of the field force and the delays caused by questionnaires being mailed out and returned, normally mean that at least a two-week period is necessary for organising a face-to-face interviewing project. A month is more reasonable. A programme of business-to-business interviews may have less personal interviews than a consumer study but they too take an inordinate amount of time to organise as the researchers struggle to set up interviews in the diaries of busy managers.
The greatest advantages of the telephone against face-to-face interviewing is its speed and low cost. These are most evident in business-to-business market research.
In favourable circumstances, perhaps five to six 20-minute interviews with managers in industry can be completed in a day over the telephone. In the same time only 1 or 2 interviews can be achieved face-to-face.
The telephone is also quicker and cheaper than face-to-face interviews since there is no time wasted in travel between interview points.
The telephone has a number of strong arguments in favour, particularly with cost and speed. However, there are sometimes good reasons for not using telephone interviews. Visuals are sometimes difficult to use and if respondents need to consider a number of pre-determined factors in order to test their views it is often hard for the respondents to hold more than five or six factors in their mind.
Furthermore, the lack of personal contact prohibits the interviewer assessing respondents and obtaining an extra feel for what is behind the reply.
Despite these limitations, the advantages of the telephone in data collection are considerable and the method is likely to continue to make inroads against face-to-face interviews.
The factor that influences the response rate of a postal survey more than anything else is the interest that respondents have in the subject. A postal or e-survey of customers is likely to achieve a higher response than one of non-customers because there is an interest in and a relationship between customers and the sponsor of the study.
Response rates of 30% and higher from a single mailing are quite common when the survey is on behalf of a company with some apparent authority such as British Gas or a major national water company. In contrast, respondents receiving a questionnaire through the post enquiring about the type of pen they use would most probably yield a low response (less than 5 per cent is likely), because the subject is not compelling.
This fundamental point means that researchers should avoid using postal surveys except when respondents are highly motivated to answer.
Self-completion surveys depend on suitable databases containing the correct names and postal or e-mail addresses of respondents. If lists are out-of-date, contain inaccuracies in spelling of the names and addresses, or are made up of unsuitable respondents, the questionnaires will fall on stony ground and the response rates will be low.
Web surveys, or e-mail surveys as they are sometimes known, first found their place in research by replacing the slower and more expensive methodology of self-completion postal surveys. Now, with technological advancements, they have become the preferred data collection method for many customer satisfaction and staff satisfaction surveys, as well as product and service feedback and conference evaluations within many business-to-business markets.
There are many different reasons for conducting online surveys including cost savings, time savings and improved data accuracy levels through automatic routing.
Today, most e-surveys are completed by invitation and this would typically be through an e-mailed invitation. Therefore, if you are thinking about carrying out an e-survey you first need to check the following details:
If you have answered yes to all the above then an online e-survey may be the right technique for collecting your data.