TwinsLungs: TwinsLungs


Comparing lung function for twins between rural and urban environments


A dataset with 14 observations on the following 3 variables.

Pair Code for the twin pair: A - G
Environ Living environment: Rural or Urban
Percent Percentage of radioactivity remaining in lungs


This dataset is from a study to compare the effect of living environment (rural or urban) on human lung function, where the researchers were able to locate seven pairs of twins with one twin in each pair living in the country, the other in a city. To measure lung function, twins inhaled an aerosol of radioactive Teflon particles. By measuring the level of radioactivity immediately and then again after an hour, the scientists could measure the rate of “tracheobronchial clearance." The percentage of radioactivity remaining in the lungs after an hour told how quickly subjects' lungs cleared the inhaled particles.


“Urban factor and tracheobronchial clearance" by Per Camner and Klas Philipson in Archives of Environmental Health, V. 27 (1973), page 82. Data can be found in Introduction to Mathematical Statistics and its Applications, 2nd Edition by Richard J. Larson and Morris L. Marx. Englewood Cliffs, NJ: Prentice Hall, p. 548.

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