Fig. 2From: Road traffic noise and registry based use of sleep medicationSplines with 95% confidence limits of the associations between nighttime road traffic noise shown from 35Â dB and sleep medication use for the total year. The vertical lines on the x-axis indicate number of observations. General additive model adjusted for age, sex, educational level, household income, population density, marital status, alcohol use, smoking status, physical activity, night shift work, and rail traffic noiseBack to article page