Table 1

Criteria for assigning a level of evidence to recommendations

Level of Evidence


Level 1

Randomized control trials without important limitations

Level 2

Randomized control trials with important limitations

Observational studies (non-randomized clinical trials or cohort studies) with overwhelming evidence

Level 3

Other observational studies (prospective cohort studies, case-control studies, case series)

Level 4

Inadequate or no data in population of interest

Anecdotal evidence or clinical experience

Kesäniemi et al. International Journal of Behavioral Nutrition and Physical Activity 2010 7:41   doi:10.1186/1479-5868-7-41

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