Glossary · Methodology
Case report and case series
In short
A case report describes what happened to a single person; a case series summarizes several such cases without a comparison group. Both are the weakest form of human data — and often the first warning.
Case reports cannot show that something works: without a comparison group it remains open whether the person would have fared the same without treatment. For side effects, on the other hand, they are valuable. Rare, serious events go unnoticed in small studies, but not in the sum of reported individual cases.
Especially for substances without marketing authorization, case reports are often the only safety data in humans. That there are few of them does not mean the problem is rare — it is just rarely written up.
In the BK-Score, case reports and uncontrolled series sit in the range of 2 to 3 for human evidence.
One case proves no effect, but it can signal a danger.
Where this comes up in the fact checks
Sources
Related terms: Observational study · SARM · BK-Score
Information only, not medical advice. The BK-Score is a subjective assessment according to disclosed rules – not a scientific evaluation. Scoring rules