Effects of Exercise Interventions and Physical Activity Behavior on Cancer Related Cognitive Impairments: A Systematic Review

Table 1

Oxford levels of evidence and grades of recommendation.

Level	Content	Grade of recommendation
1a	Systematic reviews with homogeneity in the case of randomized controlled trials	A
1b	Individual randomized controlled trials (with narrow confidence interval)
2a	Systematic reviews with homogeneity of cohort studies	B
2b	Individual cohort study (including low-quality, randomized controlled trials)
3a	Systematic reviews with homogeneity of case-control studies
3b	Individual case-control study
4	Case series (and poor-quality cohort and case-control studies)	C
5	Expert opinion without explicit critical appraisal	D