Evidence - Based Dietetics and Applied Nutrition (EBDAN): a tool for dietitians best practice

Evidence - Based Dietetics and Applied Nutrition
(EBDAN): a tool for dietitians best practice
Baladia E, Manera M, Basulto J.
Review and Position Statement Group of the Spanish Association of Dietitians and Nutritionists,
C/Consell de Cent 314 Pral B. 08007 Barcelona (Spain) www.grep-aedn.es / info@grep-
aedn.es
Introduction
Dietitians should work on the basis of the best practice knowledge. The great amount of published data on dietetics
and nutrition has created the need to summarize findings and conclusions based on the best available empirical
evidence.
Objectives
Methods
To develop a practical classification system of evidence levels for dietetics and applied nutrition science research
that will enable dietitians to make evidence-based recommendations and prescriptions.
A review was conducted to identify articles evaluating different methods of classifying studies in light of evidence
based criteria. Databases consulted included PubMed, Embase, Scopus, FSTA and Scielo. Selected articles
included those published in English, Spanish, French, Italian and German.
Results
In despite of technical literature available addressing the classification of scientific evidence, only a few authors
provide clear descriptions and even fewer studies are specifically applicable to the fields of dietetics and applied
nutrition. Moreover, only a limited number of publications take into account that one has to evaluate: the type of
study design, the quality of individual studies selected to be included in the review, the sample size and the length
of the intervention. In addition, none of the papers selected in the present review considered that the evaluation
methodology of the studies should be practical and adapted to the dietitians’ theoretical knowledge. The currently
developed tool, Evidence-Based Dietetics and Applied Nutrition (EBDAN), is surely the first system of evidence
based classification that takes all these factors into account.
Conclusions
EBDAN is a new practical tool, to be applied by dietitians, based on rational evidence in order to develop and review
guidelines, validate nutrition and health claims, establish a wide variety of recommendations as well as to apply in
preventive and therapeutic decision-making.
1. Formulate a good question
and perform a search query
2. Establish the quality
of the study
Low
Middle
High
Reject
Experimental Studies1
Observational Studies2
Level IIb
3. Establish the level of evidence and
the recommendation grade (tables 1&2)
Table 1. Level of evidence classification
Table 2. Recommendation grade
* Randomized Controlled Trial,
1 Detsky et al. System: Detsky AS, Naylor CD, O’Rourke K, et al. Incorporating variations in the quality of individual randomized trials into metaanalysis. J Clin Epidemiol. 1992;45:255-65.
2 CRD System: Khan KS, Riet G, Glanville J, Sowden AJ, Kleijnen J. Undertaking systematic reviews of research on effectiveness: CRD’s Guidance for those Carrying Out or Commissioning Reviews. Center of
Reviews and Dissemination (CRD) Report Number 4. 2.a ed. York: March; 2001.
LEVEL OF
EVIDENCE
STUDY DESIGN
RECOM.
GRADE
Ia
- Systematic review of RCT* (with statistics)
- Meta-analysis of RCT* A1
Ib
- Systematic review of RCT (without statistics)
- Review of RCT*
- RCT* (sample of more than 100 subjects)
A2
IIa
- Systematic review of Prospective Cohort Studies
- Meta-analysis of Prospective Cohort Studies B1
IIb
- RCT* (sample less than 100 subjects)
- Controlled Clinical Trials (systematic reviews, meta-
analysis, review)
- Review of Prospective Cohort Studies
- Case-Control Studies (systematic reviews, meta-analysis,
review)
- Studies (all types) with controversial results
B2
III
- Clinical Trials
- Cohort Studies (other than Prospective)
- Studies (all types) catalogued as “middle quality”
C
IV
- Expert Opinions
- Reviews (other types)
- Other types of documents
D
RECOM.
GRADE
RECOMMENDATION TYPE
A1 Recommendations with extremely unlikely variations along
the time
A2 Recommendations with unlikely variations along the time
B1 In case it is not possible to approve Ia or Ib study design, it
can be considered this group as a A2 recommendation type.
On the contrary, it will be considered as B2
B2 Recommendations with probable variations along the time
C There are limited studies or they are not supported by
enough studies. A recommendation cannot be established.
D Studies have not been found.
Póster presentado en el 3er Congreso de Dietitians Improving the
Education and Training Standards (DIETS)
Lisboa, septiembre de 2009