Effectiveness of Acceptance and Commitment Therapy for Chronic Non-Malignant Pain: A Randomized Controlled Trial

This study is evaluating whether Acceptance and Commitment Therapy (ACT) helps adults with chronic non-malignant pain (pain lasting 3 months or longer that is not caused by cancer). Sixty adult participants (ages 18-60) were randomly placed into one of three groups: ACT, Cognitive Behavioral Therapy (CBT), or Treatment as Usual (TAU, standard medical care only). Both ACT and CBT are delivered over 10 weekly sessions by a trained therapist. ACT focuses on helping people accept pain-related thoughts and feelings, become less controlled by unhelpful thinking patterns, and take action toward things that matter to them despite pain. CBT focuses on changing unhelpful thoughts about pain and building coping skills such as pacing and relaxation. The TAU group continues usual medical care without added psychological treatment. Participants complete questionnaires before and after treatment measuring pain intensity, pain acceptance, pain-related disability, psychological flexibility, catastrophic thinking about pain, anxiety, depression, and quality of life. The goal is to find out whether ACT works as well as, or better than, CBT, and whether either treatment works better than standard care alone.

Study Overview

• Status: Active, not recruiting
• Conditions: Chronic Non-Malignant Pain (Chronic Musculoskeletal Pain, Chronic Widespread Pain)
• Intervention / Treatment: Behavioral: Acceptance and Commitment Therapy (ACT); Behavioral: Cognitive Behavioral Therapy (CBT)

Detailed Description

Chronic non-malignant pain (CNMP) is associated with significant psychological distress, functional impairment, and reduced quality of life, and pharmacological treatment alone often provides limited relief. This study uses a three-arm, single-blind randomized controlled trial with a pretest-posttest parallel-group design to compare Acceptance and Commitment Therapy (ACT) against Cognitive Behavioral Therapy (CBT, active comparator) and Treatment as Usual (TAU, control).

Sixty adults (aged 18-60) with a physician-confirmed diagnosis of chronic non-malignant musculoskeletal or widespread pain (duration ≥3 months) were enrolled using purposive sampling and randomly allocated to ACT, CBT, or TAU (n=20 per group) using manual simple randomization (fishbowl method). Eligible participants scored ≥4 on the Numerical Rating Scale (pain intensity), ≥4 on the Brief Pain Inventory interference subscale, and ≥20 on the Pain Catastrophizing Scale, and were willing/able to attend all sessions. Individuals with severe psychiatric disorders, severe cognitive/neurological impairment, concurrent structured psychological treatment for pain, or unstable medical conditions were excluded.

The ACT intervention, delivered over 10 weekly sessions using a manual-based protocol adapted for chronic pain, targets the six core processes of the psychological flexibility model: acceptance, cognitive defusion, present-moment awareness, self-as-context, values clarification, and committed action. The CBT intervention, also delivered over 10 weekly sessions, targets maladaptive pain-related cognitions and behaviors through cognitive restructuring, behavioral activation, activity pacing, relaxation training, problem-solving, and coping skills. The TAU group continues routine medical/pharmacological care without structured psychological intervention.

Outcome assessors are blinded to group allocation; participants and therapists could not be blinded given the nature of the interventions. Outcomes are assessed at baseline and post-intervention using the Numerical Rating Scale (pain intensity), Chronic Pain Acceptance Questionnaire (pain acceptance), Brief Pain Inventory (pain interference), Acceptance and Action Questionnaire-II (psychological flexibility), Pain Catastrophizing Scale, Hospital Anxiety and Depression Scale, and WHOQOL-BREF (quality of life). Data collection is complete for the majority of participants; a small number of participants are currently in their final follow-up sessions before post-intervention assessment.

The study aims to (1) evaluate within-group change in ACT and CBT from pretest to posttest across all outcomes; (2) compare ACT versus CBT on post-intervention outcomes, with primary focus on pain acceptance, psychological flexibility, and pain interference; (3) examine whether change in psychological flexibility predicts change in pain interference and catastrophizing across both treatment groups; (4) compare ACT and CBT on anxiety, depression, and quality of life; and (5) compare ACT and CBT against TAU on all outcome measures. Findings are expected to clarify the comparative efficacy and mechanism of action of ACT relative to an established active treatment, contributing evidence for non-pharmacological, mechanism-informed pain management, particularly within an under-studied Pakistani population.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Pakistan
  • Punjab Province
    • Guiranwala, Punjab Province, Pakistan, 52250
      • DHQ Hospital, Gujranwala (Orthopedic Department)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Chronic non-malignant musculoskeletal pain or chronic widespread pain persisting for at least three months, without evidence of malignant pathology Aged between 18 and 60 years Current pain severity of ≥4 on the Numerical Rating Scale (NRS) Pain-related functional interference of ≥4 on the Brief Pain Inventory (BPI) interference subscale Pain catastrophizing score of ≥20 on the Pain Catastrophizing Scale (PCS) Availability and willingness to attend all intervention sessions (10 weekly sessions for either ACT or CBT) Diagnosis medically confirmed by a qualified physician (e.g., orthopedic consultant or pain specialist) prior to inclusion

Exclusion Criteria:

Presence of severe psychiatric disorders, including but not limited to psychotic disorders, schizophrenia, or bipolar disorder Severe cognitive impairment or neurological disorders that may interfere with understanding or completing study assessments Concurrent participation in other structured psychological interventions for chronic pain (e.g., CBT, ACT) Uncontrolled or unstable medical conditions that may compromise safe participation in the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ACT (Acceptance and Commitment Therapy); Participants in this arm receive Acceptance and Commitment Therapy delivered over 10 weekly sessions using a manual-based protocol adapted for chronic pain. The intervention targets six core processes: acceptance, cognitive defusion, present-moment awareness, self-as-context, values clarification, and committed action.	Behavioral: Acceptance and Commitment Therapy (ACT); A 10-session, manual-based psychological intervention targeting psychological flexibility through acceptance, cognitive defusion, present-moment awareness, self-as-context, values clarification, and committed action, delivered weekly by a trained therapist.
Active Comparator: CBT (Cognitive Behavioral Therapy); Participants in this arm receive Cognitive Behavioral Therapy delivered over 10 weekly sessions, targeting maladaptive pain-related cognitions and behaviors through cognitive restructuring, behavioral activation, activity pacing, relaxation training, problem-solving, and coping skills.	Behavioral: Cognitive Behavioral Therapy (CBT); A 10-session, manual-based psychological intervention targeting maladaptive pain-related cognitions and behaviors through cognitive restructuring, behavioral activation, activity pacing, relaxation training, problem-solving, and coping skills, delivered weekly by a trained therapist.
No Intervention: TAU (Treatment as Usual); Participants in this arm continue their routine medical/pharmacological care for chronic pain without receiving any structured psychological intervention as part of the study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Pain Acceptance	Pain acceptance will be assessed using the Chronic Pain Acceptance Questionnaire (CPAQ), a 20-item self-report measure rated on a 7-point Likert scale (0 = "never true" to 6 = "always true"), with higher scores indicating greater acceptance.	Baseline and post-intervention (Week 10)
Change in Psychological Flexibility	Psychological flexibility will be assessed using the Acceptance and Action Questionnaire-II (AAQ-II), a 7-item self-report measure rated on a 7-point Likert scale (1 = "never true" to 7 = "always true"), with higher scores indicating greater flexibility.	Baseline and post-intervention (Week 10)
Change in Pain Interference	Pain interference will be assessed using the Pain Interference subscale of the Brief Pain Inventory (BPI), rated on a 0-10 scale, with higher scores indicating greater interference with daily functioning, mood, and social activities.	Baseline and post-intervention (Week 10)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Pain Intensity	Pain intensity will be assessed using the Numerical Rating Scale (NRS), a single-item measure ranging from 0 ("no pain") to 10 ("worst imaginable pain").	Baseline and post-intervention (Week 10)
Change in Pain Catastrophizing	Pain catastrophizing will be assessed using the Pain Catastrophizing Scale (PCS), a 13-item measure rated on a 5-point scale, with higher scores indicating greater catastrophizing.	Baseline and post-intervention (Week 10)
Change in Anxiety Symptoms	Anxiety will be assessed using the anxiety subscale of the Hospital Anxiety and Depression Scale (HADS-A), a 7-item measure rated on a 0-3 scale.	Baseline and post-intervention (Week 10)
Change in Depression Symptoms	Depression will be assessed using the depression subscale of the Hospital Anxiety and Depression Scale (HADS-D), a 7-item measure rated on a 0-3 scale.	Baseline and post-intervention (Week 10)
Change in Quality of Life	Quality of life will be assessed using the WHOQOL-BREF, a self-report measure assessing physical, psychological, social, and environmental domains of quality of life.	Baseline and post-intervention (Week 10)

Collaborators and Investigators

• Sponsor: GIFT University
• Investigators: Study Director: Ather Mujitaba, Phd, GIFT University

Study record dates

Study Major Dates

• Study Start (Actual): May 13, 2026
• Primary Completion (Estimated): July 26, 2026
• Study Completion (Estimated): July 31, 2026

Study Registration Dates

• First Submitted: July 12, 2026
• First Submitted That Met QC Criteria: July 12, 2026
• First Posted (Actual): July 16, 2026

Study Record Updates

• Last Update Posted (Actual): July 16, 2026
• Last Update Submitted That Met QC Criteria: July 12, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Depression; Acceptance and Commitment Therapy; Quality of Life; Anxiety; Randomized Controlled Trial; Cognitive Behavioral Therapy; Pain Catastrophizing; Chronic Widespread Pain; Psychological Flexibility; Chronic Non-Malignant Pain; Chronic Musculoskeletal Pain; Pain Acceptance
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Mental Disorders; Behavioral Symptoms; Pathological Conditions, Signs and Symptoms; Behavior; Signs and Symptoms; Anxiety Disorders; Chronic Pain; Depression; Behavior Therapy; Psychotherapy; Behavioral Disciplines and Activities; Cognitive Behavioral Therapy; Acceptance and Commitment Therapy
• Other Study ID Numbers: GIFT/PSY/MS/2025/002

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: A formal data-sharing plan has not yet been established. This is a student thesis-based clinical trial, and decisions regarding individual participant data (IPD) sharing will depend on institutional policy, ethical approval conditions, and participant consent terms at the time of study completion.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No