Epiville

Screening

Data Collection

The SussStat procedure tests for irregularities in the DNA, called DNA adducts , that are formed when a chemical contained in Glop Indutstry's Superclean product bonds to DNA. It is this process which researchers suspect may lead to Susser Syndrome.

You receive a spreadsheet with the DNA adduct data from the laboratory, and now must use these data to categorize each subject into the categories of 'Test Positive' and 'Test Negative' for Susser Syndrome. The manufacturer of SussStat suggests that levels of DNA adducts lie on a continuum. The manufacturer suggests dichotomizing SussStat level at 12 × 10-8. Those who test at 12 × 10-8 or higher will be considered screened "positive," and everyone else will be considered screened "negative." You use this manufacturer-suggested cutpoint to categorize your subjects into Test Positive and Test Negative for SS.

When each subject returns for the one-year clinic visit, the clinician evaluates them and uses the diagnostic criteria put forth by the EDOH to categorize each subject into Disease Positive and Disease Negative. After receiving these data from the study physician, you are now ready to compare the SussStat results to the Clinician Gold Standard! In order to prepare the data for analysis, you classify each subject into a 2×2 table:

Gold Standard
Positive Negative Total
SussStat Positive 90 40 130
Negative 10 860 870
100 900 1000

[ Click here for the Interactive Exercise . ]