Most fieldwork, whether done by telephone or personal interviewing, is done by individuals recruited and organized to do fieldwork for a wide variety of research studies. Some research organizations maintain a staff of field workers on national basis; others contract out the fieldwork to organizations specializing in that phase only. Some fieldwork organizations maintain a national organization, while others have lists of independent supervisors who have groups of interviewers in their local areas. This discussion will not deal with the problems of recruiting these interviewers and maintaining the organization. When a project is approaching the fieldwork stage, the organization to be used is alerted. If it is believed that certain types of interviewers are required (e.g. men or women younger than 30) that will be stated but to a significant degree it is necessary to use those field workers who are available.
Personal interview surveys on a national basis may require hundreds of interviewers at dispersed areas around the country, supervisors who oversee their work directly, and field coordinators who control the whole process. A national telephone survey could be organized in a similar manner using the same or similar interviewers with local telephone service. The WATS service, however, however, makes it feasible to handle the telephone survey from one central location. This permits the development of a small group of full-time skilled interviewers who can be used on many projects and can be supervised closely. As a result, the data-collection process is done better on telephone surveys and this is a main reason for the growth of telephone interviewing.
For the centralized telephone project a much smaller number of interviewers (e.g. 10–40) are sufficient. If many are new interviewers, they must be given general instructions on interviewing techniques. All interviewers are then assembled for training on the specific features of the project at hand. Sometimes these are brief sessions; but for major projects of particular importance, the training session may take as long as two days. Each interviewer does a practice interview, which is then discussed with a supervisor.
For personal interview projects such centralized training is not practical. The usual procedure is to send written instructions and questionnaires to the local supervisors, who are expected to conduct the training. This means that there is considerable variation in the amount and quality of training the various interviewers receive.
To ensure that fieldwork is started and proceeds on schedule researchers establish starting and completion dates and quotas for completion by certain intervals. When materials are mailed to the fieldwork supervisors, a list of all materials is included along with a postcard to be returned, acknowledging receipt. Interviewers turn in their completed questionnaires daily to local supervisors. These are tabulated to provide a running total of completed interviews by interviewer and for the project. If the project falls behind schedule, the director can identify those who must be speeded up. Additional interviewers may be added if necessary.
As completed questionnaires begin to come in, they are edited to be sure the interviewers are proceeding properly. Any mistakes can be corrected before further interviews are made. Since most projects are on a tight schedule in the field, it is important that problems be identified as early as possible and proper action taken. In personal interviews these tabulations and checks are done by the local supervisors, with the resulting delays and variables.
Minimizing fieldwork errors:
There are many points at which errors can creep into marketing research studies during the field work phase as described above. There are general administrative and control procedures also which can improve the overall quality of fieldwork while holding costs at acceptable levels. Most research organizations pay particular attention to five factors:
1. Selection and training of field workers – interviewers or observers
2. Administrative procedures for handling projects in the field.
3. Supervision of field workers and the data collection process
4. Quality and cost control procedures
5. Validation of fieldwork
Training and supervisions of field workers has been emphasized above.