Introductory Biostatistics

1.10 Table E1.10 provides the proportions of currently married women hav-
ing an unplanned pregnancy. (Data are tabulated for several di¤erent
methods of contraception.) Display these proportions in a bar chart.

TABLE E1.10

Method of

Contraception

Proportion with

Unplanned Pregnancy

None 0.431

Diaphragm 0.149

Condom 0.106

IUD 0.071

Pill 0.037

1.11 Table E1.11 summarizes the coronary heart disease (CHD) and lung
cancer mortality rates per 1000 person-years by number of cigarettes
smoked per day at baseline for men participating in the MRFIT (Multi-
ple Risk Factor Intervention Trial, a very large controlled clinical trial
focusing on the relationship between smoking and cardiovascular dis-
eases). For each cause of death, display the rates in a bar chart.

TABLE E1.11

CHD Deaths Lung Cancer Deaths

Total N Rate/1000 yr N Rate/1000 yr

Never-smokers 1859 44 2.22 0 0

Ex-smokers 2813 73 2.44 13 0.43

Smokers

1–19 cig./day 856 23 2.56 2 0.22

20–39 cig./day 3747 173 4.45 50 1.29

b40 cig./day 3591 115 3.08 54 1.45

1.12 Table E1.12 provides data taken from a study on the association be-
tween race and use of medical care by adults experiencing chest pain in
the past year. Display the proportions of the three response categories
for each group, blacks and whites, in a separate pie chart.

TABLE E1.12

Response Black White

MD seen in past year 35 67

MD seen, not in past year 45 38

MD never seen 78 39

Total 158 144

38 DESCRIPTIVE METHODS FOR CATEGORICAL DATA