The SHARE survey utilised by OECD is more restrictive in its usage of chronic diseases compared to EHIS2, as it includes chronic diseases associated with the modifiable risks mentioned throughout the article. EHIS2 does not discriminate between chronic diseases, and thus Norwegian results may be biased upwards. 

Definition: Chronic diseases are defined for these purposes as illnesses and diseases that have lasted for at least six months, or are expected to last at least six months. People with chronic diseases here includes those with at least one or more.