title: Do sugar-sweetened beverages cause adverse health outcomes in adults? A systematic review protocol.
abstract: BACKGROUND
  Chronic diseases, such as cardiovascular disease and type 2 diabetes, impose significant burden to public health. Most chronic diseases are associated with underlying preventable risk factors, such as elevated blood pressure, blood glucose, and lipids, physical inactivity, excessive sedentary behaviours, overweight and obesity, and tobacco usage. Sugar-sweetened beverages are known to be significant sources of additional caloric intake, and given recent attention to their contribution in the development of chronic diseases, a systematic review is warranted. We will assess whether the consumption of sugar-sweetened beverages in adults is associated with adverse health outcomes and what the potential moderating factors are.
  
  
  METHODS
  Of interest are studies addressing sugar-sweetened beverage consumption, taking a broad perspective. Both direct consumption studies as well as those evaluating interventions that influence consumption (e.g. school policy, educational) will be relevant. Non-specific or multi-faceted behavioural, educational, or policy interventions may also be included subject to the level of evidence that exists for the other interventions/exposures. Comparisons of interest and endpoints of interest are pre-specified. We will include randomized controlled trials, controlled clinical trials, interrupted time series studies, controlled before-after studies, prospective and retrospective comparative cohort studies, case-control studies, and nested case-control designs. The MEDLINE, Embase, The Cochrane Library, CINAHL, ERIC, and PsycINFO databases and grey literature sources will be searched. The processes for selecting studies, abstracting data, and resolving conflicts are described. We will assess risk of bias using design-specific tools. To determine sets of confounding variables that should be adjusted for, we have developed causal directed acyclic graphs and will use those to inform our risk of bias assessments. Meta-analysis will be conducted where appropriate; parameters for exploring statistical heterogeneity and effect modifiers are pre-specified. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach will be used for determining the quality of evidence for outcomes.
  
  
  BACKGROUND
  PROSPERO CRD42014009638.
authors.forename: Candyce
authors.initials: C
authors.lastname: Hamel
authors.forename: Adrienne
authors.initials: A
authors.lastname: Stevens
authors.forename: Kavita
authors.initials: K
authors.lastname: Singh
authors.forename: Mohammed T
authors.initials: MT
authors.lastname: Ansari
authors.forename: Esther
authors.initials: E
authors.lastname: Myers
authors.forename: Paula
authors.initials: P
authors.lastname: Ziegler
authors.forename: Brian
authors.initials: B
authors.lastname: Hutton
authors.forename: Arya
authors.initials: A
authors.lastname: Sharma
authors.forename: Lise M
authors.initials: LM
authors.lastname: Bjerre
authors.forename: Shannon
authors.initials: S
authors.lastname: Fenton
authors.forename: David C W
authors.initials: DC
authors.lastname: Lau
authors.forename: Kathryn
authors.initials: K
authors.lastname: O'Hara
authors.forename: Robert
authors.initials: R
authors.lastname: Reid
authors.forename: Erinn
authors.initials: E
authors.lastname: Salewski
authors.forename: Ian
authors.initials: I
authors.lastname: Shrier
authors.forename: Noreen
authors.initials: N
authors.lastname: Willows
authors.forename: Mark
authors.initials: M
authors.lastname: Tremblay
authors.affiliation: Clinical Epidemiology Program, Centre for Practice-Changing Research, Ottawa Hospital Research Institute, 501 Smyth Road, Box 201B, Ottawa, ON K1H 8L6, Canada. dmoher@ohri.ca.
authors.forename: David
authors.initials: D
authors.lastname: Moher
mesh_terms: D001628:Beverages / Q000009:adverse effects*; D002318:Cardiovascular Diseases / Q000209:etiology; D003731:Dental Caries / Q000209:etiology; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology; D019422:Dietary Sucrose / Q000009:adverse effects*; D002149:Energy Intake; D006073:Gout / Q000209:etiology; D006266:Health Education; D006801:Humans; D024821:Metabolic Syndrome / Q000209:etiology; D009369:Neoplasms / Q000209:etiology*; D009765:Obesity / Q000209:etiology; D051436:Renal Insufficiency, Chronic / Q000209:etiology; D012107:Research Design; D013549:Sweetening Agents / Q000009:adverse effects*; D000078202:Systematic Reviews as Topic; D015201:Meta-Analysis as Topic
chemical_list: D019422:Dietary Sucrose; D013549:Sweetening Agents