Grades of recommendations and levels of evidence from the Canadian Task Force on Preventive Health Care
| GRADE OR LEVEL | RECOMMENDATION OR EVIDENCE |
|---|---|
| A | There is good evidence to recommend the clinical preventive action |
| B | There is fair evidence to recommend the clinical preventive action |
| C | The existing evidence is conflicting and does not allow a recommendation for or against the use of the clinical preventive action; however, other factors might influence decision making |
| D | There is fair evidence to recommend against the clinical preventive action |
| E | There is good evidence to recommend against the clinical preventive action |
| F | There is insufficient evidence (in quantity or quality) to make a recommendation; however, other factors might influence decision making |
| I | At least 1 properly conducted randomized controlled trial, systematic review, or meta-analysis |
| II | Other comparison trials, non-randomized studies, cohort studies, case-control studies, or epidemiologic studies, and preferably more than 1 study |
| III | Expert opinion or consensus statements |
Adapted from the Canadian Task Force on Preventive Health Care.1