TABLE 1.

Comparison of Clustering in Kawasaki Syndrome and Simulated Data Sets

	Kawasaki Syndrome
Geographic Region/Time Period	Cluster Size*	Percent of Cases in Clusters	No. Clusters	No. Simulated Clusters (Mean ± SD)
Eastern Japan; January to June (n = 20,085)	≥39	4.9	162	129.8 (±6.7)
Eastern Japan; July to December (n = 18,743)	≥36	5.1	166	136.9 (±6.8)
Western Japan; January to June, (n = 24,089)	≥46	4.9	164	128.9 (±6.7)
Eastern Japan; July to December (n = 21,912)	≥41	5.6	179	150.7 (±6.7)

^*The cluster size was arbitrarily defined as the number of cases during a 4-day period that represented approximately 5% of the Kawasaki syndrome sample for 2 time-periods and 2 geographic regions.

SD indicates standard deviation.