A single case experimental design: how do different psychological outcome measures capture the experience of a client undergoing CBT for chronic pain

Abstract

Introduction: Reports suggest that many people who experience chronic pain also experience associated mental health difficulties. Currently the first line psychotherapeutic intervention for people who experience anxiety and depression within the context of chronic pain is Cognitive Behaviour Therapy. Anecdotal clinical reports suggest that commonly used psychological outcome measures do not truly reflect the experience and improvement of clients who experience chronic pain following CBT. The present study therefore aimed to compare the outcomes of a CBT intervention within one client's journey through CBT. Methods: A single case experimental design (SCED) was used to evaluate generic measures of mood, pain specific measures of wellbeing and client specific cognitions. Results: All outcome measures suggested that the CBT intervention had been at least somewhat successful. Results suggest that the more specific the measure was to the client's experience; the more improvement was demonstrated on the measure.

Cognitive-behavioural therapy for chronic pain: determining what works for the person in front of you

“…Single-case designs provide the opportunity to tailor assessment measures to the priorities of the individual participant which may not be adequately captured by standardised measures used in RCTs. 8,11 This collaborative assessment approach is arguably more empowering to participants and is consistent with recommendations for involving people with the condition under study as active research partners. 12,13 The frequency of idiographic assessment enables more precise investigation of the time-course of changes in treatment process and outcome, which can be used to refine treatment.…”

“…12,13 The frequency of idiographic assessment enables more precise investigation of the time-course of changes in treatment process and outcome, which can be used to refine treatment. 8,11,14,15 The flexible, person-centred approach of single-case designs may be more appropriate to test the effects of psychotherapy for people with multiple comorbidities. 16 Therefore, single-case methods may be useful for participants traditionally excluded from RCTs of CBT for chronic pain due to the complexity of their mental health or medical needs.…”

“…There is a growing resurgence of interest in single-case designs as a rigorous methodological approach to address some of the identified challenges surrounding RCTs. 8–10 In this issue, Jones and Hurrell 11 report a single-case AB design consisting of repeated baseline assessments (‘A’ phase) followed by CBT during which repeated assessments were also collected (‘B’ phase) with a participant with chronic pain and depression. Jones and Hurrell collected standardised measures of psychological symptoms, pain catastrophizing and self-efficacy before and after CBT.…”

“…The study by Jones and Hurrell 11 is a useful example of the benefits of single-case designs in contrast to RCTs. Single-case designs provide the opportunity to tailor assessment measures to the priorities of the individual participant which may not be adequately captured by standardised measures used in RCTs.…”