Table 2. Trend in adjusted lung cancer rates in 37 municipalities of Rio Grande do Sul by radon exposure.

Adjusted lung cancer rates	Coef.a	95%CIb	p-valuec	Trend
Incidence rate (2013–2021)
Municipalities with low exposure probabilityd	0.27	−0.13; 0.68	0.153	Stationary
Municipalities with increased probability to exposured	1.01	0.22; 1.81	0.020	Growing
Hospitalisation rate (2000–2021)
Municipalities with low exposure probabilityd	0.46	0.08;0.85	0.021	Growing
Municipalities with increased probability to exposured	1.15	0.70; 1.60	<0.001	Growing
Total mortality rate (2000–2021)
Municipalities with low exposure probabilityd	−0.16	−0.33; 0.01	0.058	Stationary
Municipalities with increased probability to exposured	0.02	−0.33; 0.37	0.899	Stationary

Caption:

^aPrais–Winsten regression coefficient indicating the average annual change in the rate

^b95% Confidence Interval (CI) for the regression coefficient

^cStatistical significance of the trend, based on the Prais–Winsten regression

^dMunicipalities grouped based on estimated radon exposure probability derived from airborne gamma spectrometry (eU concentrations):

– Low exposure probability: lower eU levels

– Increased exposure probability: higher eU levels, indicating greater radon susceptibility