Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-20T14:33:38.307Z Has data issue: false hasContentIssue false
  • English
  • Français

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 [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

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

References

1Canadian Task Force on the Periodic Health Examination. The periodic health examination. Canadian Medical Association Journal 1979; 121: 1193–254.Google Scholar
2Goldbloom, RB. Weighing the evidence: the Canadian experience. American Journal of Clinical Nutrition 1997; 65(Suppl. 2): 584S–6S.CrossRefGoogle ScholarPubMed
3Clark, M, Oxman, AD, eds. Cochrane Reviewers' Handbook 4.1.0. In: The Cochrane Library, Issue 2, 2003.Google Scholar
4Canadian Task Force on the Periodic Health Examination. http://ctfphc.org. Accessed 9 December 1999.Google Scholar
5Oxford Centre for Evidence-based Medicine. Levels of Evidence and Grades of Recommendations. Available at http://www.cebm.jr2.ox.ac.uk/docs/level.html. Accessed 31 August 2001.CrossRefGoogle Scholar
6US Preventive Services Task Force. Guide to Clinical Preventive Services, 2nd ed. Washington, DC: US Department of Health and Human Services, 1996.Google Scholar
7Ärztliche Zentralstelle für Qualitätssicherung (ÄZQ)/Arbeitsgemeinschaft wissenschaftlichen medizihischen Fachgesechaften (AWMF). Das Leitlinien-Manval. Köln, ÄZQ/AWMF, 2000.Google Scholar
8Eccles, M, Freemantle, N, Mason, J. North of England evidence based guideline development project: guideline on the use of aspirin as secondary prophylaxis for vascular disease in primary care. North of England Aspirin Guideline Development Group. British Medical Journal 1998; 316: 1303–9.CrossRefGoogle ScholarPubMed
9Hadorn, DC, Baker, D, Hodges, JS, Hicks, N. Rating the quality of evidence for clinical practice guidelines. Journal of Clinical Epidemiology 1996; 49: 749–54.CrossRefGoogle ScholarPubMed
10Lohr, KN, Carey, TS. Assessing ‘best evidence’: issues in grading the quality of studies for systematic reviews. Joint Commission Journal on Quality Improvement 1999; 25: 470–9.Google ScholarPubMed
11Benson, K, Hartz, AJ. A comparison of observational studies and randomized, controlled trials. American Journal of Ophthalmology 2000; 30: 688.CrossRefGoogle Scholar
12Concato, J, Shah, N, Horwitz, RI. Randomized, controlled trials, observational studies, and the hierarchy of research designs. New England Journal of Medicine 2000; 342: 1887–92.Google Scholar
13Hill, A. The environment and disease: association or causation? Proceedings of the Royal Society of Medicine 1965; 58: 295–300.Google Scholar
14Rothman, KJ, Greenland, S. Modern Epidemiology. Philadelphia, PA: Lippincott-Raven, 1998.Google Scholar
15Dickersin, K. Systematic reviews in epidemiology: why are we so far behind? International Journal of Epidemiology 2002; 31: 6–12.CrossRefGoogle ScholarPubMed
16Black, N. Why we need observational studies to evaluate the effectiveness of health care. British Medical Journal 1996; 312: 1215–18.Google Scholar
17Scottish Intercollegiate Guidelines Network (SIGN). SIGN 50: A Guideline Developer's Handbook. Section 6 [online]. Available at http://www.sign.ac.uk/guidlines/fulltext/50/ sections5.html. Accessed 23 November 2001.Google Scholar