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THE RELATIVE RISK
Author(s) -
SAARI K. M.
Publication year - 1984
Publication title -
acta ophthalmologica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.534
H-Index - 87
eISSN - 1755-3768
pISSN - 1755-375X
DOI - 10.1111/j.1755-3768.1984.tb03082.x
Subject(s) - relative risk , ankylosing spondylitis , abo blood group system , medicine , disease , human leukocyte antigen , gastroenterology , risk factor , immunology , antigen , confidence interval
A relative risk (RR) indicates how many times more frequent the disease is in individuals carrying the factor (HLA antigen) relative those who lack it. RR values are calculated by the formula RR=ad:bc where a and b are the numbers of patients carrying and lacking the factor (antigen), respectively, and c and d the corresponding numbers of controls. Associations between HLA and disease may be much stronger (e.g. RR=90 in ankylosing spondylitis and RR=5.2 to 53 in acute anterior uveitis) than the classical association between blood group O and duodenal ulcer (RR=1.33) indicating a more important involvement of HLA in many diseases than of ABO in duodenal ulcer.