Confounding Issues

Question 1

How confounding can be?

Answer 1

if the distribution of age is incomparable between case and control and age is associated with test results, then age could be a confounder. The confounder leads the location of ROC curve deviates (poikkeamaan) from its true location in ROC space. Thus, it results over or under estimate in ROC diagnostic accuracy. Restriction and matching in design and using adjustment methods in statistical analysis help that confounding be prevented.

Question 2

What is said in summary?

Answer 2

Vaikka Roc analyysilla in diagnostic test evaluation on fantastiset mahdollisuuset (features) ja relevantit tulkinta of AUC a kunnon design with broad spectrum of case and control and avoidance of bias and control for confounding are necessary for a valid and reliable conclusion in the assessment=evaluation of performance of diagnostic tests.

Spectrum and bias should be considered with careful consideration in study design while confounding can be controlled in analysis as well.

Question 3

What is widely used in etiologic studies? And versus medical?

Answer 3

adjustment of confounding

little attention has been focused for the control of confounding in ROC analysis of medical published diagnostic studies.