title: Observer variation in grading sacroiliac radiography in HLA-B27 positive individuals.
mesh_terms: D000328:Adult; D001168:Arthritis / Q000000981:diagnostic imaging*; D005260:Female; D006680:HLA Antigens / Q000032:analysis*; D015796:HLA-B27 Antigen; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012446:Sacroiliac Joint / Q000000981:diagnostic imaging*
chemical_list: D006680:HLA Antigens; D015796:HLA-B27 Antigen