TABLE 2—

Final Cluster Centers Obtained Using K-Means Cluster Analysis

	Cluster
	1	2
Number of respondents	591	387
Percent of sample	60.4	39.6
Mood/memory/fatigue symptoms	.81	2.12
Musculoskeletal symptoms	.73	2.08
Gastrointestinal symptoms	.43	1.47
Throat/breathing symptoms	.42	1.29

Note. Factor values are interpretable as mean symptom scores on a scale of 0 (not present), 1 (mild), 2 (moderate), and 3 (severe).