Abstract
This thesis explores how general groups of people think about predictive genetic testing. Psychological research into individual decision-making prior to the consulting room is scarce, with our knowledge of the types of factors that influence the decision to request this service barely investigated. The research presented undertakes this task by identifying salient factors influential in the contemplation of this new health choice. The research then examines how these factors impact on genetic-testing decision-making processes and intentions in more detail. The aim is to increase scientific understanding of early decision-making in this area, by exploring the motivations of individuals who intend to request this service and also the decision-making of those individuals who will never be seen at a genetic clinic. The thesis is comprised of four studies. The first study uses an exploratory qualitative methodology, gathering focus group data to discover how groups of people who have not directly experienced predictive genetic testing think about this service. The findings suggest that people are primarily concerned with their perceived control over genetic testing decision-making processes and their risk of genetic diseases. The second and third studies use repeated measures experimental designs to manipulate perceived control (self- efficacy) over genetic-testing decisions and perceptions of disease risk. The findings revealed a complex relationship between self-efficacy in these domains, global self- efficacy, perceptions of risk and intention to undergo testing. Study two showed that when specific efficacy in these domains was experimentally decreased global perceptions of self-efficacy also reduced, alongside the desire to maintain control over these domains. Study three showed that a lack of intention to undergo genetic testing was predicted by perceptions of high disease risk, high levels of health-specific self-efficacy and the importance of this efficacy - but not levels of general self-efficacy. Additionally the results from the third study revealed that intention to undergo testing was higher when people were given no information about the genetic inheritability of a disease, indicating that that as a disease becomes 'geneticized' both control over that disease and general control may become eroded. The final study again uses a qualitative methodology, using interview data from individuals at high and low risk of disease to further examine the role of risk and self- efficacy in genetic testing decision-making, and to identify which areas of self-efficacy have most impact on intentions. The study also examines how people make sense of their 'genetic risk', how they conceptualise self-efficacy within this domain, and how they perceive these two concepts to be related. Findings from the last study suggest that levels of general self-efficacy may be relevant to decision-making when the individual's confidence is extremely high, in that the person feels confident to cope with the test result regardless of any possibility of cure or prevention. Attitudes and intentions towards genetic testing also appeared to be strongly determined by levels of disease-risk anxiety, with the attraction of testing appearing to wane when the emotional consequences of genetic testing were reflected upon. To conclude, these findings suggest that a lack of perceived control over genetic testing decision-making and disease risk has wide-reaching consequences in negatively impacting on overall perceptions of competence and well-being. The findings also suggest that for people at extremely high risk of disease, who feel both in control of any potential symptoms and value this control, genetic testing is unattractive, in robbing them of the potential for control in the future. Diseases perceived as being genetic were largely viewed as immutable and uncontrollable. On deeper reflection, decision-making in this area was often perceived as anxiety provoking and conceptualised by ambivalent and complex thinking.