When relevant, highlight the differing experiences of Shiites, Sunni Muslims, ethnic Kurds, Assyrian Christians and women.
When relevant, however, some data are presented by organizational categories.
When relevant (e.g., for Latvia), we also included the burning of harvest residues after a clearcut.
When relevant, WHO malignant cases are separately specified.
When relevant, concrete advice for policy makers was included.
When relevant, the odds ratio will be calculated.
When relevant data was unavailable, values were based on expert clinical opinion.
When relevant, we also included unpublished research (e.g., manuscripts under review, peer-reviewed conference presentations).
When relevant information was missing, we contacted study authors by email.
When relevant, post-hoc analysis was performed using the Games-Howell test (Games and Howell, 1976).
When relevant, there are practical information sheets providing information about how different examinations are performed.
