Developing a measure of informed choice in cancer screening

Abstract

The principle of informed choice has recently become incorporated into cancer screening policy. However, there has been limited empirical or theoretical work on informed choice in this particular context. The main aim of this thesis is to develop an instrument/approach that could be used to measure informed choice in both research and service settings. The principal research question is, 'What are the key domains of informed choice in cancer screening, and how best can they be measured?'Systematic reviews were undertaken to identify the relevant qualitative and quantitative studies. A qualitative study (nine focus groups and 15 individual interviews) was undertaken with people who had different experiences of screening (for breast, cervical or colorectal cancer). The purpose of the study was to identify the key domains of informed choice. Data from the qualitative study were used to define the items in the questionnaire. The questionnaire was piloted initially by sending it to a sample of 150 screening invitees and 54 replied (36%). It was then further refined and sent to 1292 people who had been invited to participate in one of the three types of screening. Of these, 553 returned a completed questionnaire (43%).Findings from the systematic reviews suggested that lay people define and conceptualise informed choice differently from researchers and policy makers. These findings were substantiated in the data from the qualitative study. The study also found that information on the disease was as important to people as information on the risks and limitations of screening. However, information may have little part to play in the choices people make. It may have more impact on outcomes such as satisfaction and anxiety. Analysis of the questionnaire data found that people had limited knowledge of the risks and consequences of screening. In addition, perceived informedness was strongly predicted by attitudes rather than the knowledge of the risk and benefits. High levels of knowledge were not a predictor of the level of choice people had.The main policy reason for promoting informed choice is to enhance autonomy and to prevent people being deceived or coerced. However, this research shows that the provision of evidence-based information alone does not necessarily mean that an informed choice is made. People may not read, want, or understand the information, and, additionally, people may not be able to carry out their intended choice. For example, people may feel that they do not have the choice to refuse screening, even though they might wish to do so. Moreover, there may be personal barriers, such as physical or mental health problems and language, or organisational barriers, such as the availability of the service/intervention and access. This research identifies the complexity of the relationship between information and choice, revealing a number of reasons why the concept of 'informed choice' requires more subtle understanding in the context of cancer screening.