Abstract
BACKGROUND: This paper provides three illustrations of how the "person-based approach" can be used to assess and enhance the acceptability and feasibility of an intervention during the early stages of development and evaluation. The person-based approach involves using mixed methods research to systematically investigate the beliefs, attitudes, needs and situation of the people who will be using the intervention. The in-depth understanding of users' perspectives derived from this research then enables intervention developers to design or modify the intervention to make it more relevant, persuasive, accessible and engaging. METHODS: The first illustration describes how relevant beliefs and attitudes of people with asthma were identified from the existing qualitative and quantitative literature and then used to create guiding principles to inform the design of a web-based intervention to improve quality of life. The second illustration describes how qualitative "think-aloud" interviews and patient and public involvement (PPI) input are used to improve the acceptability of a booklet for people with asthma. In the third illustration, iterative think-aloud methods are used to create a more accurate and accessible activity planner for people with diabetes. RESULTS: In the first illustration of the person-based approach, we present the guiding principles we developed to summarise key design issues/objectives and key intervention features to address them. The second illustration provides evidence from interviews that positive, non-medical messages and images were preferred in booklet materials for people with asthma. The third illustration demonstrates that people with diabetes found it difficult to complete an online activity planner accurately, resulting in incorrect personalised advice being given prior to appropriate modification of the planner. CONCLUSIONS: The person-based approach to intervention development can complement theory- and evidence-based development and participant input into intervention design, offering a systematic process for systematically investigating and incorporating the views of a wide range of users.