Multi-stratified multiple regression tests of the linear/no-threshold theory of radon-induced lung cancer

Conference · Thu Dec 31 04:00:00 EST 1992

OSTI ID:44919

Cohen, B L ^[1]

---

1. Univ. of Pittsburgh, PA (United States)

A plot of lung-cancer rates versus radon exposures in 965 US counties, or in all US states, has a strong negative slope, b, in sharp contrast to the strong positive slope predicted by linear/no-threshold theory. The discrepancy between these slopes exceeds 20 standard deviations (SD). Including smoking frequency in the analysis substantially improves fits to a linear relationship but has little effect on the discrepancy in b, because correlations between smoking frequency and radon levels are quite weak. Including 17 socioeconomic variables (SEV) in multiple regression analysis reduces the discrepancy to 15 SD. Data were divided into segments by stratifying on each SEV in turn, and on geography, and on both simultaneously, giving over 300 data sets to be analyzed individually, but negative slopes predominated. The slope is negative whether one considers only the most urban counties or only the most rural; only the richest or only the poorest; only the richest in the South Atlantic region or only the poorest in that region, etc., etc.,; and for all the strata in between. Since this is an ecological study, the well-known problems with ecological studies were investigated and found not to be applicable here. The {open_quotes}ecological fallacy{close_quotes} was shown not to apply in testing a linear/no-threshold theory, and the vulnerability to confounding is greatly reduced when confounding factors are only weakly correlated with radon levels, as is generally the case here. All confounding factors known to correlate with radon and with lung cancer were investigated quantitatively and found to have little effect on the discrepancy.

• OSTI ID: 44919
• Report Number(s): CONF-901010--Pt.2
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
CARCINOGENESIS
CORRELATIONS
DISEASE INCIDENCE
DOSE-RESPONSE RELATIONSHIPS
LUNGS
NEOPLASMS
RADON
REGRESSION ANALYSIS