Nutrition & Dietetics
Access the evidence
Evidence-based practice resources
The most time-efficient and systematic way of seeking research evidence to answer clinical questions is to follow the Haynes '5S' (or 5 sources) model . This model organises research into pre-appraised, synthesised (i.e. secondary) evidence and primary studies requiring critical appraisal before they can be applied in practice.
Using this approach, clinicians access 5 distinct types of evidence-based resources. They start with the most efficient resources, as these contain more mature evidence, and work their way through to the level of individual studies only if they don't find an answer.
The 5 categories are (in order of searching precedence):
- Systems (still largely hypothetical)
These are integrated computerised decision-support systems designed to improve clinician decision making. These systems, which are by no means ubiquitous, generally integrate an electronic patient health record system with some sort of evidence-based practice guidelines to generate point-of-care, patient-specific treatment recommendations.
These are online evidence summaries which are regularly updated as new evidence is generated and appraised. Conceptually similar to traditional textbooks in that they are usually arranged by clinical topic (e.g. diabetes, heart failure) for the purpose of patient management. Examples include point-of-care tools UpToDate and Best Practice, as well as evidence-based clinical practice guidelines.
Synopses are short structured abstracts of individual studies (or syntheses). They provide a brief summary and critical appraisal of a piece of research, often making recommendations for practice based on the study's quality or findings. In doing so they relieve the clinician of having to read the full article and make a judgment of its methodological quality and implications for practice.
These resources contextualise and integrate the research findings of individual studies within the larger body of knowledge of the topic. Syntheses include systematic reviews (such as those produced by the Cochrane Collaboration), the published results from consensus conferences or expert panels, meta-analyses of quantitative research, meta-syntheses of qualitative research, and critically appraised topics (CATs).
If none of the foregoing sources can provide an answer to your question, you'll need to go to the vast body of individual studies to seek evidence. This can be a time-consuming, frustrating experience if you don't know the basics of searching or the most efficient resources to use. The resources with the greatest prevalence of peer-reviewed research literature in your field should be your starting point. This should include Medline, PubMed, Embase (only available via Scopus at Flinders University) and the Cochrane Central Register of Controlled Trials (CENTRAL).
Work through the tabs above to find evidence for your topic, starting at Summaries and ending with Studies.
For a good overview of your topic, start with the TRIP database:
1. Haynes RB. Of studies, syntheses, synopses, summaries, and systems: the "5S" evolution of information services for evidence-based healthcare decisions. Evidence Based Medicine. 2006; 11:162-4.
Syntheses include systematic reviews and meta-analyses. Start with the Cochrane Database of Systematic Reviews.
Important to note: Systematic reviews are also published in general medical and allied health journals so you will also need to look for them in databases such as Medline and CINAHL.
Other subject-specific resources
Useful multidisciplinary databases