Clients rarely present with prototypical presentations for which an “off the shelf” cognitive-behavioural therapy (CBT) approach can be used, and the most frequently cited rationale for case conceptualisation is matching clients’ unique presentations and therapy goals with available theory and research. In this, it is argued that case conceptualisation guides therapy by ensuring that individual cognitive and behavioural processes are targeted, thereby maximising therapy efficacy. Therefore, therapists who are competent in case conceptualisation should achieve better outcomes. However, little is known about the relationship between competency in case conceptualisation and general CBT competence, or how competency in case conceptualisation is linked to therapy outcome. Forty audiotapes selected from an ongoing study (CoBalT: Cognitive Behavioural Therapy as an adjunct to Pharmacotherapy for Treatment Resistant Depression in Primary Care: a randomised controlled trial) were rated for competency in case conceptualisation and competence in CBT using the Collaborative Case Conceptualisation – Rating Scale (CCC-RS) and Cognitive Therapy Scale – Revised (CTS-R) respectively. The assessment of competence was carried out by independent groups of researchers with expertise in these assessments, blind to treatment outcome. Therapy outcome was measured using The Beck Depression Inventory II (BDI-II). The results showed that 1) competence in case conceptualisation shared a strong and positive relationship with general CBT competence and, 2) that competence (in case conceptualisation and general CBT competence) was associated with better treatment outcome for depression. The results highlight competence in case conceptualisation as an important facet of therapist CBT competence, and indicate that investing in the training and selection of therapists competent in case conceptualisation as well as CBT competence has the potential to enhance treatment outcomes.

The need to provide effective Cognitive Behavioural Therapy (CBT) treatments in routine clinical practice necessitates effective methods of CBT training, which are scalable and can be disseminated in populations without ready access to specialist trainers or large scale funding. This thesis seeks to add theoretical and empirical guidance to the development of evidence-based CBT training. The first chapter reviews the current literature on effective CBT training, and suggests theoretical and methodological guidance for future research on evidence-based training practices. Cohort studies (Chapters 2 – 4) examine data from former trainees for guidance on accurate CBT competence measurement and effective CBT training components. The fifth and sixth chapters report randomised-controlled trials examining the effects of internet-based training (IBT) on therapists’ competence and patient outcomes (Chapter 6). Findings from the literature review (Chapter 1) and Chapter 2 suggested the need for training effectiveness trials using treatment trial methodology, which includes ‘blind’ observer ratings of therapist behaviour as the measure of competence. Chapter 3 found that extensive training led to significant improvement in competence for trainees with a range of individual baseline characteristics. Since such extensive training is not accessible to the majority of practicing therapists, Chapter 4 examined which elements of extensive training were perceived by trainees as having the greatest positive effect on competence; thus providing empirical guidance in planning more scalable forms of training, such as IBT. Findings from the first four chapters provided guidance in planning the two randomised controlled trials outlined in Chapters 5 and 6, resulting in rigorous empirical data showing significant positive effects of IBT on therapists’ competence and on their patients’ clinical outcomes. Finally, the results of this thesis are related to the framework for developing evidence-based training, which was suggested in Chapter 1 and suggestions for future research are made.

In order to continue to improve the effectiveness of psychotherapy, researchers must identify key change processes. Unfortunately, there are disparate views in the field about the relative importance and potency of specific techniques versus relationship factors. Few measures have been developed to examine the relative contribution of these factors, particularly for child-focused treatment. The Common-Factor Therapist Competence Scale for Youth Psychotherapy (COMP-CF) was developed to address this deficit. For this study, 142 video-taped sessions of child CBT for anxiety were observed and rated by independent coders using the COMP-CF. The measure demonstrated good reliability and internal consistency. Significant between-therapist and between-session differences were noted that warrant further exploration. The COMP-CF also demonstrated initial validity when compared to other observer-rater measures of therapeutic processes such as alliance, CBT-specific competence, and adherence. Recommendations for further development and refinement are discussed. Used in conjunction with adherence measures, the competence measure developed here may help improve our understanding of the therapeutic process.