On 2015 Aug 07, Ivan Oransky commented:

Here's a second look at this study by F. Perry Wilson of Yale: http://www.medpagetoday.com/Endocrinology/Obesity/52492

On 2015 Aug 01, DAVID ALLISON commented:

Video Exaggerates Effects.

In 1954, Huff [1] showed that representing data with 2D graphics of 3D objects could mislead if geometric principles were neglected. In the video accompanying this article [2] describing liraglutide weight loss results, at 1 minute, 26 seconds, a cartoon patient injects liragultide and shrinks in size. We measured an 11.4% reduction in depicted ‘waist diameter’. If waist perimeters approximate circles, this implies an approximately equivalent percent reduction in waist circumference (WC). Yet, the investigators report only a 7.3% reduction (not placebo corrected) in mean WC with liragultide. This alone indicates that the video exaggerates average change among treated patients. Further, a simplifying approximation of the human body as a cylinder of uniform mass [3] and empirical observations [4] suggest that weight scales to WC to the power of lambda, with lambda > 1. This implies that the 11.4% waist reduction shown portrays a figure with an implied weight reduction >11.4%. Yet, mean intervention body weight dropped only 7.9%.

Concerns exist about misleading before and after photographs in weight loss advertisements [5]. Standards for weight loss drawings similarly need to avoid inadvertently misleading clinicians and patients.

David B. Allison, University of Alabama at Birmingham

Diana M. Thomas, Montclair State University

Steven B. Heymsfield, Pennington Biomedical Research Center

References

1) Huff D. How to lie with statistics. New York: Norton; 1993.

2) Pi-Sunyer X, Astrup A, Fujioka K, et al. A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management. N Engl J Med 2015;373:11-22.

3) Heymsfield SB, Martin-Nguyen A, Fong TM, Gallagher D, Pietrobelli A. Body circumferences: clinical implications emerging from a new geometric model. Nutr Metab (Lond) 2008;5:24.

4) Heymsfield SB, Heo M, Pietrobelli A. Are adult body circumferences associated with height? Relevance to normative ranges and circumferential indexes. Am J Clin Nutr 2011;93:302-7.

5) Weight Loss Advertising: An Analysis of Current Trends: A Federal Trade Commission staff report. Federal Trade Commission: https://www.ftc.gov/reports/weight-loss-advertisingan-analysis-current-trends [accessed 8/1/15].

On 2015 Aug 01, DAVID ALLISON commented:

Video Exaggerates Effects.

In 1954, Huff [1] showed that representing data with 2D graphics of 3D objects could mislead if geometric principles were neglected. In the video accompanying this article [2] describing liraglutide weight loss results, at 1 minute, 26 seconds, a cartoon patient injects liragultide and shrinks in size. We measured an 11.4% reduction in depicted ‘waist diameter’. If waist perimeters approximate circles, this implies an approximately equivalent percent reduction in waist circumference (WC). Yet, the investigators report only a 7.3% reduction (not placebo corrected) in mean WC with liragultide. This alone indicates that the video exaggerates average change among treated patients. Further, a simplifying approximation of the human body as a cylinder of uniform mass [3] and empirical observations [4] suggest that weight scales to WC to the power of lambda, with lambda > 1. This implies that the 11.4% waist reduction shown portrays a figure with an implied weight reduction >11.4%. Yet, mean intervention body weight dropped only 7.9%.

Concerns exist about misleading before and after photographs in weight loss advertisements [5]. Standards for weight loss drawings similarly need to avoid inadvertently misleading clinicians and patients.

David B. Allison, University of Alabama at Birmingham

Diana M. Thomas, Montclair State University

Steven B. Heymsfield, Pennington Biomedical Research Center

References

1) Huff D. How to lie with statistics. New York: Norton; 1993.

2) Pi-Sunyer X, Astrup A, Fujioka K, et al. A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management. N Engl J Med 2015;373:11-22.

3) Heymsfield SB, Martin-Nguyen A, Fong TM, Gallagher D, Pietrobelli A. Body circumferences: clinical implications emerging from a new geometric model. Nutr Metab (Lond) 2008;5:24.

4) Heymsfield SB, Heo M, Pietrobelli A. Are adult body circumferences associated with height? Relevance to normative ranges and circumferential indexes. Am J Clin Nutr 2011;93:302-7.

5) Weight Loss Advertising: An Analysis of Current Trends: A Federal Trade Commission staff report. Federal Trade Commission: https://www.ftc.gov/reports/weight-loss-advertisingan-analysis-current-trends [accessed 8/1/15].

On 2015 Aug 07, Ivan Oransky commented:

Here's a second look at this study by F. Perry Wilson of Yale: http://www.medpagetoday.com/Endocrinology/Obesity/52492