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. 2026 May;30(35):1–174. doi: 10.3310/GJHS2715

Effects and costs of a group-based educational intervention to reduce opioid use in people with chronic pain: I-WOTCH RCT.

Harbinder K Sandhu, Katie Booth, Sheeja Manchira Krishnan, Charles Abraham, Sharisse Alleyne, Shyam Balasubramanian, Lauren Betteley, Tom Bromilow, Dawn Carnes, Andrea D Furlan, Vijay S Gc, Kirstie L Haywood, Maddy Hill, Cynthia P Iglesias-Urrutia, Ranjit Lall, Andrea Manca, Dipesh Mistry, Joe We Moss, Sian Newton, Vivien P Nichols, Jennifer Noyes, Emma Padfield, Anisur Rahman, Kate Seers, Jane Shaw, Nicole Ky Tang, Stephanie Jc Taylor, Colin Tysall, Martin Underwood, Sam Eldabe
PMCID: PMC13200030  PMID: 42138313

Abstract

BACKGROUND

The long-term use of strong opioids for chronic non-cancer pain puts people at risk of serious harm.

OBJECTIVES

To test the effectiveness and cost-effectiveness of a multicomponent intervention targeting opioid use for the treatment of chronic pain.

DESIGN

A multicentred randomised controlled trial with embedded process evaluation.

SETTING

Primary care.

PARTICIPANTS

Adults using strong opioids for non-malignant chronic.

INTERVENTIONS

Participants were randomised 1 : 1 (using a minimisation programme stratified by geographical locality, baseline pain intensity score and baseline morphine equivalent dose) to either usual care (an educational booklet and relaxation compact disc) or usual care plus the I-WOTCH intervention; 3 day-long group sessions delivered by a nurse and lay facilitator, plus a one-to-one session and ongoing telephone contact from the nurse to support opioid tapering.

MAIN OUTCOME MEASURES

The two primary outcomes were Patient-Reported Outcomes Measurement Information System Pain Interference Short Form (8A), and proportion using no opioids, at 12 months.

RESULTS

We randomised 608 people. At 12 months, there was no between-group difference in Patient-Reported Outcomes Measurement Information System Pain Interference Short Form (8A) scores; mean difference, -0.52 (95% confidence interval -1.94 to 0.89). At 12 months, 65/225 (29%) of people in the intervention group and 15/208 (7%) of people in usual-care group reported using no opioids [odds ratio 5.55 (95% confidence interval 2.80 to 10.99)], absolute difference, 21.7% (95% confidence interval 14.8 to 28.6). Over a lifetime horizon, I-WOTCH is on average associated with an incremental cost of £9277 per person, and provides an additional 0.314 quality-adjusted life-years. The deterministic incremental cost per quality-adjusted life-year gained was £29,543. The I-WOTCH intervention may be cost-effective compared to best usual care. The process evaluation suggested group support and shared experience were important to those trying to taper.

LIMITATIONS

The opioid use analysis is based solely on participant self-report. The findings only apply to people willing to consider opioid reduction and may not apply to a more complex secondary care population. The results may not be applicable to people using very high opioid doses.

CONCLUSIONS

The I-WOTCH intervention helps substantially more people stop opioids than best usual care without adversely affecting pain interference.

FUTURE WORK

The I-WOTCH intervention should be tested in different healthcare settings and other populations.

TRIAL REGISTRATION

This trial is registered as Current Controlled Trials ISRCTN49470934.

FUNDING

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 14/224/04) and is published in full in Health Technology Assessment; Vol. 30, No. 35. See the NIHR Funding and Awards website for further award information.

Plain language summary

Many people use strong opioid drugs to help them to live with chronic (long-lasting) pain. But they are addictive and can have serious side effects. Does the I-WOTCH support programme for people using strong opioid drugs for chronic pain both help people live better with their pain and reduce their opioid use? We worked with 191 general practices in England to find people taking strong opioid drugs for non-cancer pain. Using a computer, we randomly allocated participants into two groups. Both received best current care including an advice booklet and relaxation compact disc. The other group were also offered the I-WOTCH intervention. This consists of 3-day-long group discussion/education sessions on pain management and opioid use, led by a nurse and someone with pain who had stopped using opioids, followed by a 1-hour session with a nurse to discuss opioid dose reduction, and ongoing telephone support. One year after receiving treatment, we wanted to know if people had reduced their opioid drugs and if we had changed how pain affected their lives. In total, 608 people joined the study. At 1 year, there was no difference between the groups in how pain affected their lives. In the best usual-care group, 1 in 14 people (7%) were taking no opioids at 1 year. While in the I-WOTCH group, one in four people (29%) were taking no opioids at 1 year. How pain affected people was neither better nor worse in either group. The I-WOTCH intervention may represent good value for the NHS. The I-WOTCH intervention can help people living with chronic non-malignant pain stop using strong opioids without affecting how pain interferes with their lives.

Full text of this article can be found in Bookshelf.

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