PH 1700 Homework 6
10.14: A 1980 study investigated the relationship between the use of OCs and the
development of endometrial cancer . The researchers found that of 117 endometrial-
cancer patients, 6 had used the OC Oracon at some time in their lives, whereas 8 of the 395
controls had used this agent. Test for an association between the use of Oracon and the
incidence of endometrial cancer, using a two-tailed test.
Used OC Oracon
Never used OC
10.20: Otolaryngology Many children have tympanostomy tubes surgically inserted in their
ears to reduce hearing loss associated with persistent otitis media and prevent recurrences
of episodes of otitis media after tubes are inserted. However, acute otorrhea (a discharge
from the external ear indicating inflammation of the external or middle ear), where middle
ear fluid drains through the tube, is a common side effect with tympanostomy tubes. A
clinical trial was conducted (Van Dongen et al. ) among children 1-10 years of age with
prior symptoms of otorrhea comparing efficacy of (i) antibiotic eardrops, (ii) oral
antibiotics, and (iii) observation without treatment, referred to below as observation.
Children were seen at home by study physicians at 2 weeks and 6 months after
randomization. The primary outcome was the presence of otorrhea at 2 weeks observed by
study physicians. The results are given in Table 10.22. Provide a point estimate and a 95%
CI for the prevalence of otorrhea in the ear drop group.
The point estimate for the prevalence of otorrhea in the ear drop group is 0.053.