wie erkenne ich, ob ein selbsttest wissenschaftlich fundiert ist? — what are common causes?

To assess whether a self-test is scientifically sound, check these criteria: 1) Has the test been validated in independent, peer-reviewed studies? 2) Are the effect sizes of measured biomarkers or genetic variants clinically relevant (not just statistically significant)? 3) Does the test have regulatory approval or CE marking for medical diagnostics? 4) Are results interpreted by a qualified healthcare professional? 5) Is the study population representative of you? Common causes of unsoundness include: small sample sizes, lack of control groups, overinterpretation of weak associations (e.g., single gene variants with tiny effects), commercial bias without transparency, and absence of replication studies. Many DNA tests for skin aging or weight loss rely on marketing rather than solid evidence. Don't be fooled by colorful reports – ask for the underlying studies and check if the findings are reproducible in the general population.