Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2016 Apr;24(4):772-80.
doi: 10.1002/oby.21255.

Weight change among people randomized to minimal intervention control groups in weight loss trials

Affiliations
Meta-Analysis

Weight change among people randomized to minimal intervention control groups in weight loss trials

David J Johns et al. Obesity (Silver Spring). 2016 Apr.

Abstract

Objective: Evidence on the effectiveness of behavioral weight management programs often comes from uncontrolled program evaluations. These frequently make the assumption that, without intervention, people will gain weight. The aim of this study was to use data from minimal intervention control groups in randomized controlled trials to examine the evidence for this assumption and the effect of frequency of weighing on weight change.

Methods: Data were extracted from minimal intervention control arms in a systematic review of multicomponent behavioral weight management programs. Two reviewers classified control arms into three categories based on intensity of minimal intervention and calculated 12-month mean weight change using baseline observation carried forward. Meta-regression was conducted in STATA v12.

Results: Thirty studies met the inclusion criteria, twenty-nine of which had usable data, representing 5,963 participants allocated to control arms. Control arms were categorized according to intensity, as offering leaflets only, a single session of advice, or more than one session of advice from someone without specialist skills in supporting weight loss. Mean weight change at 12 months across all categories was -0.8 kg (95% CI -1.1 to -0.4). In an unadjusted model, increasing intensity by moving up a category was associated with an additional weight loss of -0.53 kg (95% CI -0.96 to -0.09). Also in an unadjusted model, each additional weigh-in was associated with a weight change of -0.42 kg (95% CI -0.81 to -0.03). However, when both variables were placed in the same model, neither intervention category nor number of weigh-ins was associated with weight change.

Conclusions: Uncontrolled evaluations of weight loss programs should assume that, in the absence of intervention, their population would weigh up to a kilogram on average less than baseline at the end of the first year of follow-up.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Weight change over time, control group category A.
Figure 2
Figure 2
Weight change over time, control group category B.
Figure 3
Figure 3
Weight change over time, control group category C.
Figure 4
Figure 4
95% prediction intervals for weight loss at 3, 6, and 12 months.

Comment in

References

    1. Hartmann‐Boyce J, Johns D, Aveyard P, et al. Managing Overweight and Obese Adults: The Clinical Effectiveness of Long‐term Weight Management Schemes for Adults. Oxford: University of Oxford; 2013.
    1. Tsai AG, Wadden TA. Systematic review: an evaluation of major commercial weight loss programs in the United States. Ann Inter Med 2005;4142:56‐66. - PubMed
    1. Carvajal R, Wadden TA, Tsai AG, Peck K, Moran CH. Managing obesity in primary care practice: a narrative review. Ann N Y Acad Sci 2013;1281:191‐206. - PMC - PubMed
    1. JH Lavin, A Avery, SM Whitehead, et al. Feasibility and benefits of implementing a slimming on referral service in primary care using a commercial weight management partner. Public Health 2006;120:872‐881. - PubMed
    1. Hajek P, Humphrey K, McRobbie H. Using group support to complement a task‐based weight management programme in multi‐ethnic localities of high deprivation. Patient Educ Counsel 2010;80:135‐137. - PubMed

Publication types

MeSH terms