J A Dawson1, K A Kaiser2,3, O Affuso3,4, G R Cutter5, D B Allison2,3. 1. Department of Nutritional Sciences, College of Human Sciences, Texas Tech University, Lubbock, TX, USA. 2. Office of Energetics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL, USA. 3. Nutrition Obesity Research Center, University of Alabama at Birmingham, Birmingham, AL, USA. 4. Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, AL, USA. 5. Section on Research Methods and Clinical Trials, Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL, USA.
Abstract
BACKGROUND: It has not been established whether control conditions with large weight losses (WLs) diminish expected treatment effects in WL or prevention of weight gain (PWG)-randomized controlled trials (RCTs). SUBJECTS/ METHODS: We performed a meta-analysis of 239 WL/PWG RCTs that include a control group and at least one treatment group. A maximum likelihood meta-analysis framework was used to model and understand the relationship between treatment effects and control group outcomes. RESULTS: Under the informed model, an increase in control group WL of 1 kg corresponds with an expected shrinkage of the treatment effect by 0.309 kg (95% confidence interval (-0.480, -0.138), P=0.00081); this result is robust against violations of the model assumptions. CONCLUSIONS: We find that control conditions with large WLs diminish expected treatment effects. Our investigation may be helpful to clinicians as they design future WL/PWG studies.
BACKGROUND: It has not been established whether control conditions with large weight losses (WLs) diminish expected treatment effects in WL or prevention of weight gain (PWG)-randomized controlled trials (RCTs). SUBJECTS/ METHODS: We performed a meta-analysis of 239 WL/PWG RCTs that include a control group and at least one treatment group. A maximum likelihood meta-analysis framework was used to model and understand the relationship between treatment effects and control group outcomes. RESULTS: Under the informed model, an increase in control group WL of 1 kg corresponds with an expected shrinkage of the treatment effect by 0.309 kg (95% confidence interval (-0.480, -0.138), P=0.00081); this result is robust against violations of the model assumptions. CONCLUSIONS: We find that control conditions with large WLs diminish expected treatment effects. Our investigation may be helpful to clinicians as they design future WL/PWG studies.
Authors: David B Allison; Mai A Elobeid; Mark B Cope; David W Brock; Myles S Faith; Stephanie Vander Veur; Robert Berkowitz; Gary Cutter; Theresa McVie; Kishore M Gadde; Gary D Foster Journal: Med Decis Making Date: 2009-08-12 Impact factor: 2.583
Authors: O Affuso; K A Kaiser; T L Carson; K H Ingram; M Schwiers; H Robertson; F Abbas; D B Allison Journal: Obes Rev Date: 2013-09-30 Impact factor: 9.213
Authors: Linda C Tapsell; Maureen Lonergan; Marijka J Batterham; Elizabeth P Neale; Allison Martin; Rebecca Thorne; Frank Deane; Gregory Peoples Journal: BMJ Open Date: 2017-07-13 Impact factor: 2.692
Authors: Elizabeth P Neale; Linda C Tapsell; Allison Martin; Marijka J Batterham; Cinthya Wibisono; Yasmine C Probst Journal: Food Nutr Res Date: 2017-07-03 Impact factor: 3.894