UWRLD99, a new serum biomarker, is being studied for the early identification of pancreatic cancer. UWRLD99 concentrations (measured in international units [IU] per dL) have been reported to be increased in pancreatic cancer patients. The image below depicts test results from 200 volunteers ("healthy") and 190 patients with biopsy-proven pancreatic cancer ("diseased"). The researchers used a threshold of 200 IU/dL to establish the sensitivity and specificity of UWRLD99 for pancreatic cancer (indicated by the solid vertical line). Which of the following would most likely be observed if they had selected a lower cutoff, as indicated by the dashed vertical line?

Question

UWRLD99, a new serum biomarker, is being studied for the early identification of pancreatic cancer. UWRLD99 concentrations (measured in international units [IU] per dL) have been reported to be increased in pancreatic cancer patients. The image below depicts test results from 200 volunteers ("healthy") and 190 patients with biopsy-proven pancreatic cancer ("diseased"). The researchers used a threshold of 200 IU/dL to establish the sensitivity and specificity of UWRLD99 for pancreatic cancer (indicated by the solid vertical line).  Which of the following would most likely be observed if they had selected a lower cutoff, as indicated by the dashed vertical line?

Quizplus · Accepted Answer

Eductional Objective: The cutoff value of a quantitative diagnostic test determines whether a given result is interpreted as positive or negative.  Lowering the cutoff point typically causes more patients with the disease to test positive, decreasing the number of false negatives and increasing test sensitivity.  Consequently, more patients without the disease will also test positive, resulting in an increased number of false positives and decreased specificity.

UWRLD99, a New Serum Biomarker, Is Being Studied for the Early