title: A mortality study of the significance of extrasystoles in an insured population.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D005117:Cardiac Complexes, Premature / Q000401:mortality*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007352:Insurance, Life; D008297:Male; D008875:Middle Aged