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Questionnaires in health psychology consist of a standard set of questions with accompanying instructions concerning attitudes, beliefs, perceptions or values concerned with health, illness or health care. Ideally, a questionnaire will have been demonstrated to be a reliable and valid measure of the construct(s) it purports to measure.

Questionnaires vary in objectives, content (especially in their generic versus specific content), question format, the number of items, and sensitivity or responsiveness to change. Questionnaires may be employed in cross-sectional and longitudinal studies. When looking for changes over time, the responsiveness of a questionnaire to clinical and subjective changes is a crucial feature. A questionnaire’s content, sensitivity and extent, together with its reliability and validity, influence a questionnaire’s selection. Guides are available to advise users on making a choice that contains the appropriate generic measure or domain of interest (e.g., Bowling, 2001, 2004). These guides are useful as they include details on content, scoring, validity and reliability of dozens of questionnaires for measuring all of the major aspects of psychological well-being and quality of life, including disease-specific and domain-specific questionnaires and more generic measures.

The investigator must ask: What is it that I want to know? The answer will dictate the selection of the most relevant and useful questionnaire. The most important aspect of questionnaire selection is therefore to match the objective of the study with the objective of the questionnaire. For example, are you interested in a disease-specific or broad-ranging research question? When this question is settled, you need to decide whether there is anything else that your research objective will require you to know. Usually the researcher needs to develop a specific block of questions that will seek vital information concerning the respondents’ socio-demographic characteristics. This block of questions can be placed at the beginning or the end of the main questionnaire.

Questionnaire content may vary from the highly generic (e.g., How has your health been over the last few weeks? Excellent, Good, Fair, Poor, Very Bad) to the highly specific (e.g., Have you had any arguments with people at work in the last two weeks?). Questionnaires vary greatly in the number of items that are used to assess the variable(s) of interest. Single-item measures use a single question, rating or item to measure the concept or variable of interest. For example, the now popular single verbal item to evaluate health status: During the past four weeks how would you rate your health in general? Excellent, Very good, Good, Fair, Poor. Single items have the obvious advantages of being simple, direct and brief.

Questionnaires remain one of the most useful and widely applicable research methods in health psychology. A few questionnaire scales have played a dominant role in health psychology research over the last few decades. Figure 7.4 shows the number of items in the ISI Web of Knowledge database for three of the most popular scales. Over the 20-year period 1990–2009, usage of scales designed to measure health status has been dominated by three front-runners: the McGill Pain Questionnaire (Melzack, 1975), the Hospital Anxiety and Depression Scale (HADS; Zigmond and Snaith, 1983), and the SF-36 Health Survey (Brazier et al., 2002). The SF-36 is by far the most utilized scale in clinical research, accounting for around 50% of all clinical studies (Figure 7.3).

Figure 7.3 Trends in numbers of health psychology studies using different research measures and methods, 1990–2009

Source: Marks (2013)