Methodological limitations of biomedical research on the SR

The weakness of the evidence (#93) has specific methodological causes. The main ones:

• Confounders: weather, geomagnetic activity, time of day/year, lifestyle and psyche act simultaneously and it is difficult to separate them from the influence of the SR.
• Difficult isolation of exposure: the SR field is ubiquitous and very weak; it cannot simply be "switched off" and "switched on", so a clean control condition is lacking.
• Risk of publication bias: studies with a "positive" finding are published more easily than null findings, which skews the overall picture.
• Low statistical power: small samples and low replicability increase the proportion of false-positive results.

These limitations do not refute the possibility of a biological action of the SR — but they point out why existing claims must be approached critically and why no health recommendations can be derived from the current data. Well-designed, pre-registered and replicated studies with clear control of exposure are still lacking.

*Cluster M file — part of the Schumann resonance knowledge base.*