Sample size in prognostic factor research

thank you all for the input! actually this was the intention of my question, i do not want a sample size calculation to justify my observation is powered etc, i wanted it to choose the number of confounders to adjust without overfitting (in an explanatory model to show the association of a prognostic factor with an outcome). For now my strategy was to include established and well-known risk factors (e.g. age and comorbidities) and then it is okay to adjust too much (more than the rule of thumb with 10 EPV). > here it would be amazing to have something like the pmsampsize package from Riley et al.