Scoping activities and research question development

NHMRC conducted initial scoping activities during 2021 to refine the scope of the review of 2013 Australian Dietary Guidelines (the 2013 Guidelines). These included stakeholder surveys, limited literature searches and a review of international food-based dietary guidelines. A wide-ranging list of potential research topic areas were identified for consideration during this initial scoping period.

The Dietary Guidelines Expert Committee (the Expert Committee) prioritised this preliminary list of potential topics over a series of meetings. Topics were prioritised based on the impact on public health and wellbeing and on the likelihood that the evidence-base has changed enough since the release of the 2013 Guidelines to change the recommendations. Topics also needed to be related to whole foods, food groups or dietary patterns.

The following table lists the broad research questions identified as a priority for review and their respective level of priority using the process outlined in the Prioritisation Process Report.

Very high priority High priority Moderate priority Low priority

Intake/exposure and health outcomes for:

  • dietary patterns relevant at a population level
  • animal vs plant sources of protein
  • high vs low/no intake of ultra-processed foods

 

Relationship between dietary patterns and/or food intakes and sustainability outcomes was identified as a very high priority and is intended to be addressed via a separate process.

Intake/exposure and health outcomes for:

  • meal patterns (frequency of eating)
  • red vs white meat intake
  • high vs low/no intake of legumes/pulses

Contextual factors and consumption aligned with guidelines, including:

  • eating environment/context (e.g. family meals, use of technology during meal times, school/workplace/community factors)
  • food literacy/skills
  • food security
  • Interventions/strategies to improve dietary patterns and eating behaviours aligned with the guidelines across the life course. Identified as a high priority, however may be addressed separately as relates to implementation.

High vs low/no intake and health outcomes for:

  • beverages (including sugar-sweetened, artificially-sweetened, fruit juice, water, tea/coffee)
  • dairy
  • dairy alternatives
  • added sugar

Intake/exposure and health outcomes for:

  • aspects of macronutrient source/quality
  • food source and type of fat in the diet
  • meal patterns (other than frequency of eating)
  • food processing, preparation and cooking (excluding ultra-processed foods)

High vs low intakes and health outcomes for:

  • red meat
  • poultry
  • fish and/or seafood
  • egg
  • nut and/or seeds
  • fats and oils
  • total sugars intake
  • grains and cereals
  • fruit
  • vegetables

Contextual factors and consumption aligned with guidelines, including:

  • key barriers and enablers (excluding eating environment, food literacy/skills and food security)
  • cultural factors

 

The topic areas prioritised for review of the evidence do not necessarily reflect the priority of the recommendations within the guidelines. Lower priority research questions may include topics critical to national dietary guideline recommendations. These may be considered using:

  • existing evidence from the 2013 Guidelines where the evidence is not likely to have changed enough to change the recommendations since their release
  • systematic reviews published by recognised international groups.

Further information on the scoping activities, topic prioritisation, research question development and how lower priority research questions will be addressed is available in the Prioritisation Process Report.

Current activities

NHMRC is undertaking additional evidence scoping and mapping activities to make the most effective use of limited resources and avoid duplication of existing quality research.

Recent, high-quality published systematic reviews will be used (where available) to address the high and very high priority research questions in the table above.

Relevant systematic reviews will be identified through:

  1. literature searches for systematic reviews (targeted database searches and identification of reviews published by key international groups)
  2. a public call for systematic reviews which was open from 1 August to 11 September 2023.
     

Following the completion of both the literature search and public call for systematic reviews, next steps include:

  • screening the evidence (check alignment with eligibility criteria, including methodology criteria)
  • mapping eligible reviews against the high and very high priority research questions
  • identifying the ‘most relevant’ reviews (based on scope, currency and risk of bias) for each research question and gaps in the systematic review literature
  • seeking the advice of the Expert Committee to select appropriate reviews to be used to update the evidence underpinning the 2013 Guidelines, with the aim of achieving good coverage across high and very high priority questions
  • seeking the advice of the Expert Committee to prioritise critical gaps in the evidence where new evidence reviews may be required.

Visit the Priority research questions page for more detail about the research questions and for existing systematic reviews considered in the evidence review process.

To select existing systematic reviews for use in the evidence review process and identify critical gaps where new evidence reviews may be required, the Expert Committee will consider a range of factors including:

  • whether the identified existing systematic reviews are appropriate for the research question
  • whether the identified systematic reviews are sufficiently methodologically robust that their findings can be relied upon to answer the research question
  • the impact on public health and wellbeing
  • the likelihood that the evidence-base has changed enough to change recommendations since the development of the 2013 Guidelines.

Due to finite project resources, only a limited number of new reviews may be commissioned to address gaps in the priority research questions. Any priority research questions that remain unaddressed will be noted as evidence gaps to inform future reviews.