Stephen J.LurieMD, PhD, Senior Editor
To the Editor: Graves disease is the most common cause of hyperthyroidism in the United States, yet early events in its pathogenesis remain unknown.1 A cluster of 8 Graves disease cases over 21 months within a US Army Special Forces group provided an opportunity to investigate potential initiators of this disorder.
A case-control study was used to compare each patient to 6 control Special Forces subjects matched for age and sex. Patients and controls were interviewed and administered a detailed questionnaire followed by physical examination and laboratory testing. Medical and immunization records were reviewed. Nominal data were compared between cases and controls by testing that the common odds ratio equaled 1 using the uniformly most powerful unbiased test based on the conditional distribution derived from Gart, with exact P values computed as 2 times the exact 1-sided P value.2,3 Continuous and ordinal data were compared using analysis of variance. To reduce the risk of committing a type I error by comparing multiple variables, P values were adjusted with a Bonferroni correction.
Burch HB, Bernet VJ, Plotkin FR, McCord CF, Howard RS, Solomon BL, Magdycz WP, Craig SC. Graves Disease in a US Army Special Forces Group. JAMA. 2002;288(23):2975-2976. doi:10.1001/jama.288.23.2975-JLT1218-7-1