This thesis covers key issues within clinical and health psychology over three chapters. Chapter 1 examines coeliac disease and its impact in older people to help provide much needed insight into the problems encountered. Coeliac disease in older age has often been ignored within the literature and thus, little is known of its impact. This literature review provides a clearer understanding of what is already known as well as highlighting areas which need further exploration. Chapter 2 centers on the recruitment process of a larger study which examined the neurological and psychological overlap between autism and psychosis. This detailed the importance of building a good rapport between researchers and external services to gather participants, as well as the obstacles which may present when working with this particular clinical group. Chapter 3 looks more specifically at the impact childhood abuse can have on experiencing psychosis, particularly in how it may affect symptomatology. Positive symptoms, such as hallucinations, have been heavily studied with findings indicating a strong link with childhood abuse. However, the presence of negative symptoms has received little attention. Thus, this chapter seeks to address this problem