A physical examination was used to screen for breast cancer

A physical examination was used to screen for breast cancer in 2,500 women with biopsy-proven adenocarcinoma of the breast and in 5,000 age- and race-matched control women. The results of the physical examination were positive (i.e., a mass was palpated) in 1,800 cases and in 800 control women, \\ all of whom showed no evidence of cancer at biopsy. The sensitivity of the physical examination was:

Solution

Answer: Sensitivity in physical examination is defined as the proportion of patients with the condition who are test positive. The sensitivity can be calculated by dividing the number of patients who are test positive with the condition, by the total number of patients which are used to screen for condition.

Here, the total number of patients with biopsy proven adenocarcinoma of the breast are 2500 while number of patients who are test positive with breast cancer are 1800, sensitivity can be calculated as,

(1800/2500)x100 = 72%

Hence the sensitivity of physical examination was 72%.