Methodology
The 5-level evidence system
Levels compare topics inside this database only. They are not medical approval or endorsement.
- Level A
Stronger Clinical Evidence
542 studies in databaseRelatively higher-quality human studies compared with other topics in this database, e.g. multiple RCTs or systematic reviews. This does not mean it is standard or approved care.
- Level B
Emerging Clinical Evidence
499 studies in databaseSeveral human studies exist, but sample sizes, methodology, or follow-up remain limited, so conclusions are not firm.
- Level C
Early Human Research
2896 studies in databaseEarly human evidence such as case series or small samples, often without a control group.
- Level D
Preclinical Evidence
21191 studies in databaseEvidence comes from animal or laboratory studies and has not been confirmed in humans.
- Insufficient
Insufficient Evidence
3213 studies in databaseThere is currently not enough data to draw conclusions about benefit or risk for this topic.
What levels do not tell you
- • They do not mean SVF is approved to treat that condition.
- • They do not predict that you would get the outcomes seen in studies.
- • They do not replace assessment by your treating physician.