source("http://192.38.117.59/~linearpredictors/datafiles/readVitaminD.R")

women <- subset(vitaminD, category == 2)
women$bmigroup <- (women$bmi >= 25) + (women$bmi >= 30)

## Poland is used as reference group in the linear regressions

model1 <- lm(log10(vitd) ~ relevel(country, ref = "6"), data = women)
round(confint(model1), digits = 3)

model2 <- lm(log10(vitd) ~ relevel(country, ref = "6") + bmi, data = women)
round(confint(model2), digits = 3)