Background: Interventions for young children with autism are increasingly delivered through parents. This thesis investigated baseline and process variables associating with quality of parent-therapist alliance in a parent-mediated intervention for autism, including variables relating to parents' causal beliefs and perspectives. Participants: 77 parents and 6 therapists from a RCT of a parent-mediated intervention for autism (PACT). Method: A sequential exploratory mixed methods approach, with an intermediary instrument development phase. Baseline variables, investigated for the full sample of 77 cases, comprised demographic variables, parental dichotomous causal belief variables, and a therapist average fidelity variable. Thematic analysis of intervention session transcripts informed the development of the Parental Perspectives Coding Scheme (PPCS), a video-based scheme for rating the quality of parent 'Expression' and therapist 'Integration' of parental perspectives during intervention. 5 overarching themes were initially identified, these were collapsed into three items for the PPCS; Interpretation of the Child (IOC), Parent Actions and Strategies (PAS) and Parental Self Disclosures (PSD). Item inter-rater reliabilities were satisfactory to good. Parent-therapist dialogue, for a sub-sample of 20 cases, was coded using the PPCS to create process variables for the Expression and Integration of parental perspectives. Initial analyses identified baseline and process variables with significant univariate associations with alliance; these were included in separate multivariate models of parent-rated alliance and therapist-rated alliance. Results: Parent-rated and therapist-rated alliance did not correlate. PPCS Expression and Integration scores were higher in the high parent-rated alliance group but the difference was non-significant. Parents who cited MMR as a possible cause of their child's autism rated the alliance significantly lower than those who did not. Parents with no post-16 qualifications rated the alliance significantly higher than those with higher qualifications. Each factor contributed independently to a multiple regression model, together explaining 18.3% of variance in parent-rated alliance. Therapist-rated alliance significantly correlated positively with therapist fidelity and with PPCS variables for parent Expression and therapist Integration; together these explained 58.8% of variance in therapist-rated alliance. Conclusions: Therapists should be aware that parents may rate the alliance differently from themselves and that different factors associate with their ratings. Parents' causal beliefs and level of education may influence their ratings of alliance in specific interventions.

This dissertation uses a modified systematic literature review to look at working with parents and carers within child and adolescent psychotherapy, and to consider this tasks relationship to therapeutic outcomes for children and adolescents. The topic is important because psychotherapy with children and adolescents inevitably involves additional relationships. The literature indicates the way this undertaking has been regarded has varied through the history of psychodynamic child and adolescent psychotherapy. Numerous writers reflect on the ongoing neglect and absence of systematic thinking in relation to the task of work with parents and carers. This lack of attention is understood to have been influenced by the traditional model of child and adolescent psychotherapy where the source of the child or adolescent’s distress or difficulty was regarded as being primarily intrapsychic. What is now known regarding the current and active nature of the child or adolescent’s relationship with the parent or carer, and the power and persistence of the parent-child bond has resulted in an acknowledgement of the need for a more equitable balance of focus between internal and external factors. In acknowledging that the external can no longer be seen as peripheral there are compelling clinical reasons to work with parents and carers. This undertaking should not be seen as dependant on the therapist’s orientation or interest. The significant scope of possibilities for work with parents and carers within child and adolescent psychotherapy is explored; however there is a lack of data relating to the clinical effectiveness of these approaches. The future need is for systematic thinking, and the development of practice guidelines for this clinical task.