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An empirical study validating a measure of service support for CBT and a systematic review of the prevalence of co-occurring Post-traumatic Stress Disorder and Obsessive-Compulsive Disorder

Evans, Ffion 2020. An empirical study validating a measure of service support for CBT and a systematic review of the prevalence of co-occurring Post-traumatic Stress Disorder and Obsessive-Compulsive Disorder. ClinPsy Thesis, Cardiff University.
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The following large-scale research project (LSRP) comprises of two papers which are thematically distinct. The first half of the LSRP presents an empirical paper which validates a measure of service support for Cognitive Behavioural Therapy (CBT). The second paper is focused on establishing the prevalence of co-occurring PTSD and OCD. Both papers are unrelated to an initial LSRP project planned in 2018-19, which fell through due to service issues. A second empirical project was designed which focused on predictors of therapist competence and NHS ethical approval and sought to recruit practitioners delivering CBT for PTSD as part of a randomised controlled trial. This project used a novel measure of service support for CBT. This measure had not been previously validated and as a result preliminary tests of validity were embedded within the study design. As a result of delays in NHS ethics and recruitment for this project, a third study was designed, which focused primarily on the validation of this measure. This study was approved by Cardiff University’s ethics committee. The systematic review was devised when the second project was in preparation, and as a result is thematically linked to PTSD. CBT has become more widely available to the public through the National Health Service (NHS).. The evidence-base for the effectiveness of CBT is extensive and is predicated on the availability of supports for therapists. The degree to which the delivery of CBT is supported by appropriate infrastructure and resource is not yet clear. The first paper aims to address this issue through validating a measure of service support for CBT. An existing measure is reviewed by a panel of experts before being piloted with a diverse sample of CBT therapists. The resulting measure is shorter and is comprised of six thematically distinct components: access to physical resources; suitability of the clinical environment; clinical supervision; time to offer flexible sessions and prepare; working outside the clinic; professional development. It has demonstrated good content validity, temporal stability and internal consistency. Construct validity is demonstrated through positive correlations with work engagement and practitioner wellbeing. Therapist recruitment stalled during the development of the COVID-19 pandemic and a smaller sample was recruited than planned. The study confirmed that the measure is a valid and reliable index of service support and extends the application of the Job-Demands-Resources (JDR) model (a model of occupational stress) to CBT practitioners. The JDR model suggests that job resources stimulate work engagement which in turn predicts positive organisational outcomes such as work performance. The study confirmed that support for the delivery of CBT was associated with better engagement with work and greater practitioner wellbeing. Future research may therefore wish to address whether job resources can influence practitioner competence or clinical outcomes. The second paper is focused on establishing the prevalence of co-occurring PTSD and OCD. Information available to the public indicates that PTSD and OCD commonly co-occur. However, it is not clear whether this is supported by high quality research evidence. Related systematic reviews have indicated that trauma may lead to the development of OCD, with some authors suggesting that the presence or absence of PTSD is not relevant. This review therefore aimed to clarify the prevalence of co-occurring OCD and PTSD through a systematic review of the literature. A broad search strategy was devised, and four relevant databases were searched. Data was extracted from twenty-five relevant articles, which were quality assessed and reviewed. This review highlighted that there are few studies which address this research question. Most report rates of co-morbidity across multiple psychiatric disorders. As a result, most studies recruit samples which are too small to estimate the prevalence of co-occurring PTSD and OCD specifically. Furthermore, significant methodological differences across studies make it difficult to compare across groups and a wide range of current and lifetime prevalence rates are reported. The review suggested that some populations may show higher rates of co-morbidity, including those accessing specialist treatment, women and veterans. Some studies indicated that OCD is more prevalent among those with diagnoses of PTSD than those with an experience of trauma (but no PTSD). Several studies indicate that a majority of people develop OCD after PTSD, and that this group may also experience more severe symptoms. Both reviews make contributions to clinical practice. The first paper refines and validates an index of service support for CBT which may be used for clinical audit and service development. It also suggests that service providers concerned with employee engagement and wellbeing may look to workplace resources to support staff. The second paper indicates that specific groups may be more vulnerable to developing co-morbid PTSD and OCD and require a thorough assessment to inform treatment planning.

Item Type: Thesis (DClinPsy)
Date Type: Completion
Status: Unpublished
Schools: Psychology
Subjects: B Philosophy. Psychology. Religion > BF Psychology
Date of First Compliant Deposit: 30 September 2020
Last Modified: 30 Sep 2021 01:30

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