Health Psychology. Michael Murray
may often be missing. It is therefore almost impossible for new investigators to repeat a published intervention with any exactitude in their own settings.
Interviews (Semi-structured)
Semi-structured interviews are designed to explore the participant’s view of things with the minimal amount of assumptions from the interviewer. A semi-structured interview is more open-ended than a structured interview and allows the interviewee to address issues that he/she feels are relevant to the topics raised by the investigator (see Qualitative research methods below). Open-ended questions are useful in this kind of interview. They have several advantages over closed-ended questions. The answers will not be biased by the researcher’s preconceptions as much as closed-ended questions can be. The respondents are able to express their opinions, thoughts and feelings freely, using their own words in ways that are less constrained by the particular wordings of the question. The respondents may have responses that the structured interview designer has overlooked. They may have in-depth comments that they wish to make about the study and the topics that it is covering that would not be picked up using the standard questions in a structured interview.
In preparing for the interview the researcher should develop an interview guide. This can include a combination of primary and supplementary questions. Alternatively, the researcher may prefer to have a list of themes to be explored. However, it is important that the researcher does not formally follow these in the same order but rather introduces them at the appropriate time in the interview. Prior to the interview, the researcher should review these themes and order them from the least invasive to the more personal.
Interviews (Structured)
A structured interview schedule is a prepared, a standard set of questions that are asked in person, or perhaps by telephone, of a person or group concerning a particular research issue.
Literature Search
An essential skill in any research project is to carry out a literature search. Usually this will be best achieved using keywords. The key data in all scholarly publications consist of the title, the abstract, which is a summary of 100 to 250 words, and the keywords that are listed with the data about the article. By inserting keywords into any search engine, it is possible to obtain a comprehensive list of scholarly research reports, dissertations and conference papers, books and monographs. One popular search engine is Google Scholar. Another major database for researchers is the ‘ISI Web of Knowledge’. This contains a large selection of peer-reviewed publications from journals with a proven track record of high-quality publications. Examples of the results from searches of the health psychology literature are shown in Figures 7.1 and 7.4.
Longitudinal Designs
Longitudinal designs involve measuring responses of a single sample on more than one occasion. The measurements may be prospective or retrospective. Prospective longitudinal designs allow greater control over the sample, the variables measured and the times when the measurements take place. Such designs are superior to cross-sectional designs because one is better able to investigate hypotheses of causation when the associations between variables are measured over time. Longitudinal designs are among the most powerful designs available for the evaluation of treatments and of theories about human experience and behaviour, but they are also the most expensive in terms of labour, time and money.
Meta-analysis
Meta-analysis is the use of statistical techniques to combine the results of primary studies addressing the same question into a single pooled measure of effect size, with a confidence interval. The analysis is often based on the calculation of a weighted mean effect size in which each primary study is weighted according to the number of participants. A meta-analysis follows a series of steps, as follows: (1) develop a research question; (2) identify all relevant studies; (3) select studies on the basis of the issue being addressed and methodological criteria; (4) decide which dependent variables or summary measures are allowed; (5) calculate a summary effect; and (6) reach a conclusion in answer to the original research question.
Mixed Methods Research
Methodology that involves collecting, analysing and integrating quantitative and qualitative research. Examples can be found in Creswell and Clark (2007), Johnson et al. (2007), Lucero et al. (2016) and Kuenemund et al. (2016).
Narrative Approach
This approach is concerned with the desire to seek insight and meaning about health and illness through the acquisition of data in the form of stories concerning personal experiences. The narrative approach assumes that human beings are natural storytellers and that the principal task of the psychologist is to explore the different stories being told (Murray and Ziegler, 2015). The most popular source of material for the narrative researcher is the interview. The focus of the narrative interview is the elicitation of storied accounts from the interviewee. This can take various forms. The life-story interview is the most extended form of interview. As its name implies, the life-story interview seeks to obtain an extended account of the person’s life. The primary aim is to make the participant at ease and encourage him/her to tell their story at length.
Narrative analysis (NA) can take various forms. It begins with a repeated reading of the text to identify the story or stories within it. The primary focus is on maintaining the narrative integrity of the account. The researcher may develop a summary of the narrative account that will help identify the structure of the narrative, its tone and the central characters. It may be useful to engage in a certain amount of thematic analysis to identify some underlying themes. But this does not equate with narrative analysis. NA involves trying to see the interconnections between events rather than separating them. Having analysed one case, the researcher can then proceed to the next, identifying similarities and differences in the structure and content of the narratives.
Observational Studies
The term ‘observational study’ is used to describe research carried out to evaluate the effect of an intervention or treatment that does not have the advantages of a control group. A single group of patients is observed at various points before, during and after the treatment in an attempt to ascertain the changes that occur as a result of the treatment. There are strict limitations on the conclusions that can be reached as a consequence of the lack of a control group (e.g., see Randomized controlled trials below). However, there are occasions when a randomized controlled trial is impossible to carry out because of ethical or operational difficulties.
Participatory Action Research
Participatory action research (PAR) is a version of action research (see above) that deliberately seeks to provoke some form of social or community change.
Power and Power Analysis
Power refers to the ability of a study to find a statistically significant effect when a genuine effect exists. The power (1–ß) of a statistical test is the complement of ß, the Type II or beta error probability of falsely retaining an incorrect H0. Statistical power relies on three parameters: (1) the significance level (i.e., the Type I error probability or α level); (2) the size(s) of the sample(s); and (3) an effect size parameter defining H1 and thus indicating the degree of deviation from H0 in the underlying population.
Cohen (1973) found that psychology studies had about a 50% chance of finding a genuine effect owing to their lack of statistical power. The situation has changed in the last 40 years but it remains problematic. This lack of power is caused by study samples being too small to permit definite conclusions. Given the easy availability of free software online, there can be little excuse for not doing a power analysis before embarking on a research project. Funding agencies, ethics boards, research review panels and journal editors