This is a silly attitude. Maybe you should do some salutations to the sun god Ra if evidence isn't significant.
> Catching cancer early is of great importance. Hence the yearly breast control checks.
Breast cancer screening isn't annual (in women or men).
The shaman does their useless ritual once a year and people are satisfied they are protected from black magic until the next annual checkup.
Feel free to do salutation to the false god of large scale metastudies :).
Here you already know causation. Early diagnosis is proven of great benefit for many diseases. It's more effective to specially study different groups of people and see what does and doesn't work.
Btw here breast cancer is biannual indeed, annual if you had it. Might differ per country.