Weak associations between prognostic biomarkers and disease in preliminary studies illustrates the breach between statistical significance and diagnostic discrimination

RR or OR should be expressed as diagnostic sensitivity/specificity plots. Usually predictive values will identify whether or not there is potential diagnostic value that is economically reasonable. Very weak diagnostic relationships produce very low positive predictive values. Great caution should be exercised when considering weak associations for diagnostic use, especially if the biomarker is not a modifiable risk factor.