ReviewPain research & management
A comparison between enriched and nonenriched enrollment randomized withdrawal trials of opioids for chronic noncancer pain.
Review in Pain research & management. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 54 papers, 14 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
54 citing papers in PubMed, 14 syntheses or guidelines pooled it, 123 citations in OpenAlex.
- Impact of treatment duration on the effectiveness of opioid analgesia: a systematic review and meta-analysis.The British journal of general practice : the journal of the Royal College of General Practitioners · 2026Pooled it
- Drug treatments for fibromyalgia: systematic review and network meta-analysis of randomised trials.BMJ medicine · 2026Pooled it
- Pooled it
- Comparative effectiveness and safety of analgesic medicines for adults with acute non-specific low back pain: systematic review and network meta-analysis.BMJ (Clinical research ed.) · 2023Pooled it
- CDC Clinical Practice Guideline for Prescribing Opioids for Pain - United States, 2022.MMWR. Recommendations and reports : Morbidity and mortality weekly report. Recommendations and reports · 2022Guideline
- [Recommendations of the second update of the LONTS guidelines : Long-term opioid therapy for chronic noncancer pain].Schmerz (Berlin, Germany) · 2020Pooled it
- [Method report of the second update of the guidelines on long-term opioid therapy for chronic noncancer pain].Schmerz (Berlin, Germany) · 2020Guideline
- Pooled it
- Comparison of effect sizes between enriched and nonenriched trials of analgesics for chronic musculoskeletal pain: a systematic review.British journal of clinical pharmacology · 2017Pooled it
- Pharmacologic management of chronic neuropathic pain: Review of the Canadian Pain Society consensus statement.Canadian family physician Medecin de famille canadien · 2017Pooled it
- Pharmacologic interventions for treating phantom limb pain.The Cochrane database of systematic reviews · 2016Pooled it
- [Methodology of the development of the updated LONTS guidelines for long-term administration of opioids in noncancer pain].Schmerz (Berlin, Germany) · 2015Pooled it
- Opioids compared to placebo or other treatments for chronic low-back pain.The Cochrane database of systematic reviews · 2013Pooled it
- Pharmacological management of chronic neuropathic pain: revised consensus statement from the Canadian Pain Society.Pain research & managementGuideline
- The MOBILE Study-A Phase IIa Enriched Enrollment Randomized Withdrawal Trial to Assess the Analgesic Efficacy and Safety of ASP8477, a Fatty Acid Amide Hydrolase Inhibitor, in Patients with Peripheral Neuropathic Pain.Pain medicine (Malden, Mass.) · 2017Trial
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- Trial
- Methodological considerations for analyzing enriched enrolment randomized withdrawal trials.Clinics (Sao Paulo, Brazil) · 2026Article
- Chronic pain in older adults with chronic diseases: prevalence, perceived interference, and management strategies.BMC geriatrics · 2025Article
- Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundAn enriched enrollment randomized withdrawal (EERW) design excludes potential participants who are nonresponders or who cannot tolerate the experimental drug before random assignment. It is unclear whether EERW design has an influence on the efficacy and safety of opioids for chronic noncancer pain (CNCP).
objectivesThe primary objective was to compare the results from EERW and non-EERW trials of opioids for CNCP. Secondary objectives were to compare weak versus strong opioids, subgroups of patients with different types of pain, and the efficacy of opiods compared with placebo versus other drugs.
methodsMEDLINE, EMBASE and CENTRAL were searched up to July 2009, for randomized controlled trials of any opioid for CNCP. Metaanalyses and meta-regressions were conducted to compare the results. Treatment efficacy was assessed by effect sizes (small, medium and large) and the incidence of adverse effects was assessed by a clinically relevant mean difference of 10% or greater.
resultsSixty-two randomized trials were included. In 61 trials, the duration was less than 16 weeks. There was no difference in efficacy between EERW and non-EERW trials for both pain (P=0.6) and function (P=0.3). However, EERW trials failed to detect a clinically relevant difference for nausea, vomiting, somnolence, dizziness and dry skin⁄itching compared with non-EERW. Opioids were more effective than placebo in patients with nociceptive pain (effect size=0.60, 95% CI 0.49 to 0.72) and neuropathic pain (effect size=0.56, 95% CI 0.38 to 0.73).
conclusionEERW trial designs appear not to bias the results of efficacy, but they underestimate the adverse effects. The present updated meta- analysis shows that weak and strong opioids are effective for CNCP of both nociceptive and neuropathic origin.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.