dental {dstat}

Dental Problems Caused by Smoking

Description

Data from NHANES 2011-2012 containing 441 matched pairs of a daily cigarette smoker and a never smoker, recording the extent of periodontal disease. Pairs were matched for sex, age, black race, education in five categories, and ratio of family income to the poverty level.

Usage

data("dental")

Format

A data frame with 441 observations on the following 5 variables.

smoker

Periodontal disease in the daily-smoker

control

Periodontal disease in the never smoker

y

Smoker-minus-control pair difference

age

Age <= 50 > 50

dose

Cigarettes smoked per day by the smoker <10 >=10

Details

Excluding wisdom teeth, 6 measurements are taken for each tooth that is present, up to 28 teeth. Following Tomar and Asma (2000), a measurement indicates periodontal disease if either there is a loss of attachment of at least 4mm or a pocket depth of at least 4mm. The first individual has 11 measurements indicative of periodontal disease, out of 106 measurements, so pcteither is 100*11/106 = 10.38 percent.

Source

Data are from the National Health and Nutrition Examination Survey 2011-2012 and were used as an example in Rosenbaum (2017). In the second edition of Design of Observational Studies, these data are discussed in the chapter entitled Evidence Factors. Although the same 2x441 individuals were used here and in Rosenbaum (2017), the pairing was slightly changed to be exact for age>50.

References

Rosenbaum, P. R. (2017) The general structure of evidence factors in observational studies. Statist Sci 32, 514-530. <doi:10.1214/17-STS621>

Tomar, S. L. and Asma, S. (2000) Smoking attributable periodontitis in the US: Findings from NHANES III. J Periodont 71, 743-751.

US National Health and Nutrition Examination Survey 2011-2012. www.cdc.gov/nchs/nhanes/index.htm

Examples

data(dental)
attach(dental)
boxplot(y~dose:age)
abline(h=0)
detach(dental)
rm(dental)