A systematic search and qualitative review of reporting bias of lifestyle interventions in randomized controlled trials of diabetes prevention and management

Abstract

BackgroundScholars have documented presumptions regarding the relationships between diet, exercise, weight, and type 2 diabetes. However, it is unclear to what extent researchers contribute to these presumptions, and how often these relationships are thoroughly delineated within the context of randomized controlled trials (RCTs). Thus, the aim was to conduct a systematic search and qualitative, thematic analysis of RCTs focusing on lifestyle interventions for diabetes prevention or management, to examine how researchers discuss body weight in 1) the rationale and design of their RCTs; and 2) their presentation and interpretation of their findings.MethodsWe completed an electronic search for records published between 2007 and November 2016. Selection criteria included: RCTs with a follow-up period of ≥12 months; adult participants with type 2 diabetes/pre-diabetes; lifestyle interventions classified as dietary, exercise, and/or behavioural; primary outcomes of incident diabetes and complications, mortality, cardiovascular disease, and quality of life; and secondary outcomes of glycemic control and blood pressure. Nineteen articles were identified for inclusion and subject to thematic content analysis.ResultsObesity and weight loss figured prominently in the rationale and outcomes of the majority of the articles, despite intentional exclusion of “weight loss” and “obesity” as search terms. There was ambiguity over whether weight loss was classified as inclusive to the intervention, an outcome, or a measure of adherence. Results revealed that authors frequently engaged in “spin reporting” by pooling data from intervention and control groups to test the relationship between weight lost and outcomes and in their presentation of results.ConclusionsResearchers need to be aware of their biases and assumptions regarding body weight in designing, analyzing, and interpreting lifestyle interventions for diabetes prevention and management.

Exploring attitudes toward taxation of sugar-sweetened beverages in rural Michigan

“…Dietary behavior change interventions have produced mixed results [ 98 ]. Indeed, reporting issues may limit drawing conclusions of nutrition/lifestyle interventions [ 99 , 100 ]. Educational interventions that focus on SSB have produced at best short-term, mixed results [ 101 ].…”

“…A SSB tax is framed as a policy response to “obesity”, which itself is commonly framed as a product of personal irresponsibility [ 14 ]. However, concerns over economic well-being, equity, free choice, and stigmatization are competing frames in the SSB taxation debate [ 6 , 15 ].…”

Media, ‘Fat Panic’ and Public Pedagogy: Mapping Contested Terrain

“…Traditional mass media and digital media constitute a vital part of this jigsaw ‐ interlocking with policy, prejudice and public health pedagogies in complex and as yet only partially understood ways ‐ but they do not constitute the whole picture. Hence, ongoing efforts to challenge the war on obesity (Greenhalgh, ) need to be multi‐pronged and diverse in scope, ranging from updated critiques of science and epidemiology (Bombak, ; Bombak, Riediger, Bensley, Ankomah, & Mudryj, ; Riediger, Bombak, Mudryj, Bensley, & Ankomah, ) to re‐framing studies of weight‐related stigma with reference to macro‐social structures (Monaghan, ). Finally, it follows that when seeking to develop competency to critique the weight‐centred health paradigm (O'Hara & Taylor, ), or at least foster greater reflexivity when discussing obesity, interested parties may wish to acknowledge and learn from some of the above scholarship.…”