16. An epidemiologic study of
breast cancer among elderly women followed 1,000 women, 65-79 years
of age, without evidence of breast cancer over several years. Every
two years the investigators examined the women for breast cancer.
The results were as follows: 12 new cases at the first evaluation,
11 new cases at the second evaluation, 23 new cases at the third
evaluation, and 28 new cases at the fourth (and final) evaluation.
The investigators also noted that 40 women had...