Celestina Barbosa-Leiker1, Sterling McPherson2, Mary Rose Mamey3, G Leonard Burns3, Matthew E Layton4, John Roll5, Walter Ling6. 1. College of Nursing, Washington State University, Spokane, WA, United States; Department of Psychology, Washington State University, Pullman, WA, United States; Program of Excellence in Addictions Research, Washington State University, Spokane, WA, United States; Translational Addictions Research Center, Washington State University, Spokane, WA, United States. Electronic address: celestina@wsu.edu. 2. College of Nursing, Washington State University, Spokane, WA, United States; Department of Psychology, Washington State University, Pullman, WA, United States; Program of Excellence in Addictions Research, Washington State University, Spokane, WA, United States; Translational Addictions Research Center, Washington State University, Spokane, WA, United States. 3. Department of Psychology, Washington State University, Pullman, WA, United States. 4. Program of Excellence in Addictions Research, Washington State University, Spokane, WA, United States; Translational Addictions Research Center, Washington State University, Spokane, WA, United States; Washington State University Medical Sciences, Spokane, WA, United States. 5. College of Nursing, Washington State University, Spokane, WA, United States; Program of Excellence in Addictions Research, Washington State University, Spokane, WA, United States; Translational Addictions Research Center, Washington State University, Spokane, WA, United States. 6. Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, United States; Integrated Substance Abuse Programs, University of California, Los Angeles, CA, United States.
Abstract
BACKGROUND: The Clinical Opiate Withdrawal Scale (COWS) is used to assess withdrawal in clinical trials and practice. The aims of this study were to examine the inter-item correlations and factor structure of the COWS in opioid-dependent men and women. METHODS: This is a secondary data analysis of the National Drug Abuse Treatment Clinical Trials Network 0003, a randomized clinical trial that compared buprenorphine/naloxone tapering strategies. The trial included 11 sites in 10 US cities. Participants were opioid-dependent individuals (n=516) that had data on the COWS. The COWS at study baseline was analyzed in this study. RESULTS: Inter-item correlations showed weak to moderate relationships among the items. A 1-factor model did not fit the data for men (comparative fit index (CFI)=.801, root mean square error of approximation (RMSEA)=.073, weighted root mean square residual (WRMR)=1.132) or women (CFI=.694, RMSEA=.071, WRMR=.933), where resting pulse rate was not related to withdrawal for men, and yawning and gooseflesh skin was not related to withdrawal for women. A reduced model comprised of only the 8 items that were significantly related to the construct of withdrawal in both men and women, and an exploratory 2-factor model, were also assessed but not retained due to inconsistencies across gender. CONCLUSIONS: When traditional psychometric models are applied to the COWS, it appears that the scale may not relate to a single underlying construct of withdrawal. Further research testing the hypothesized factor structure in other opioid-dependent samples is needed.
BACKGROUND: The Clinical Opiate Withdrawal Scale (COWS) is used to assess withdrawal in clinical trials and practice. The aims of this study were to examine the inter-item correlations and factor structure of the COWS in opioid-dependent men and women. METHODS: This is a secondary data analysis of the National Drug Abuse Treatment Clinical Trials Network 0003, a randomized clinical trial that compared buprenorphine/naloxone tapering strategies. The trial included 11 sites in 10 US cities. Participants were opioid-dependent individuals (n=516) that had data on the COWS. The COWS at study baseline was analyzed in this study. RESULTS: Inter-item correlations showed weak to moderate relationships among the items. A 1-factor model did not fit the data for men (comparative fit index (CFI)=.801, root mean square error of approximation (RMSEA)=.073, weighted root mean square residual (WRMR)=1.132) or women (CFI=.694, RMSEA=.071, WRMR=.933), where resting pulse rate was not related to withdrawal for men, and yawning and gooseflesh skin was not related to withdrawal for women. A reduced model comprised of only the 8 items that were significantly related to the construct of withdrawal in both men and women, and an exploratory 2-factor model, were also assessed but not retained due to inconsistencies across gender. CONCLUSIONS: When traditional psychometric models are applied to the COWS, it appears that the scale may not relate to a single underlying construct of withdrawal. Further research testing the hypothesized factor structure in other opioid-dependent samples is needed.
Authors: Douglas M Ziedonis; Leslie Amass; Marc Steinberg; George Woody; Jonathan Krejci; Jeffrey J Annon; Allan J Cohen; Nancy Waite-O'Brien; Susan M Stine; Dennis McCarty; Malcolm S Reid; Lawrence S Brown; Robert Maslansky; Theresa Winhusen; Dean Babcock; Greg Brigham; Joan Muir; Deborah Orr; Betty J Buchan; Terry Horton; Walter Ling Journal: Drug Alcohol Depend Date: 2008-09-20 Impact factor: 4.492
Authors: Kelly E Dunn; Elise M Weerts; Andrew S Huhn; Jennifer R Schroeder; David Andrew Tompkins; George E Bigelow; Eric C Strain Journal: Addict Biol Date: 2018-10-08 Impact factor: 4.280