Abstract
Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating disorder characterized by persistent fatigue that is unresponsive to rest. Despite extensive intervention research, no gold standard treatment for ME/CFS has yet been identified, although Cognitive-Behavioral Therapy (CBT)-based intervention approaches have shown some promise. This dissertation evaluated Cognitive Behavioral Stress Management (CBSM) for patients diagnosed with CFS and their partners. CBSM is based on a neuroimmune model of CFS, in which symptoms are seen as prompting distress reactions and cyclically intensifying symptoms. CBSM is intended to facilitate the development of stress management skills to interrupt this cycle. Previous trials of CBSM for patients diagnosed with CFS have yielded mixed results.
We explored whether symptomatic and intervention-specific heterogeneity influenced CBSM efficacy. First, variations in ME/CFS case definitions yield a heterogeneous patient group. Notably, despite that post-exertional malaise (PEM) is considered a cardinal feature of the disorder, it is not a required symptom according to the commonly applied 1994 Centers for Disease Control and Prevention case definition for CFS. We considered whether patients' PEM status moderated effects of CBSM. Second, therapist adherence and competence in terms of delivering interventions are likely to impact outcomes. We adapted a fidelity rating system for audio recordings of group CBT to video recordings of group CBSM, with sessions double-coded to assess interrater reliability. We then evaluated whether adherence and competence variables were associated with patient outcomes at follow-up.