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History of the concept of ‘levels of evidence’ and their current status in relation to primary prevention through lifestyle interventions

Published online by Cambridge University Press:  02 January 2007

A Kroke ,
H Boeing ,
K Rossnagel  and
SN Willich
A Kroke*
Affiliation:
Institute of Social Medicine, Epidemiology, and Health Economics, Charité, Berlin, Germany Department of Epidemiology, German Institute of Human Nutrition, Potsdam–Rehbrücke, Germany Research Institute of Child Nutrition, Heinstück 11, D-44225 Dortmund, Germany
H Boeing
Affiliation:
Department of Epidemiology, German Institute of Human Nutrition, Potsdam–Rehbrücke, Germany
K Rossnagel
Affiliation:
Institute of Social Medicine, Epidemiology, and Health Economics, Charité, Berlin, Germany
SN Willich
Affiliation:
Institute of Social Medicine, Epidemiology, and Health Economics, Charité, Berlin, Germany
*
*Corresponding author: Email Kroke@fke-do.de
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Abstract

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Primary prevention is a major option to reduce the burden of chronic disease in populations. Because lifestyle interventions have proved to be effective, lifestyle recommendations including nutritional advice are made abundantly. However, both their credibility and their effectiveness are often considered not to be high. Therefore, scientific evidence should form the basis of recommendations and, as in clinical medicine, a rational approach should be followed for the evaluation of evidence. In this paper, the development and current concepts of ‘levels of evidence’ as they are applied in clinical medicine are outlined and their impact on evidence-based recommendations is discussed. Next, the question is raised as to how far the existing schemes are applicable to the evaluation of issues pertaining to primary prevention through lifestyle changes. Current schemes were developed mainly for clinical research questions and therefore place major emphasis on randomised controlled trials as the main and most convincing evidence in the evaluation process. These types of study are rarely available for lifestyle-related factors and might even not be feasible to obtain. Arguments are advanced to support the notion that a modification of currently existing ‘levels of evidence’ as developed for clinical research questions might be necessary. Thereby, one might be able to accommodate the specific aspects of evidence-related issues of recommendations for primary prevention through lifestyle changes, like dietary changes.

Keywords

Public health nutritionEvidenceEpidemiology
Type
Research Article
Information
Public Health Nutrition , Volume 7 , Issue 2 , April 2004 , pp. 279 - 284
Copyright
Copyright © CAB International 2004

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