Table 1. Demographic and Clinical Characteristics by Clusters.

	Healthy Controla (n=57)		Cluster 1 (n=13)		Cluster 2 (n=71)		Cluster 3 (n=30)		Cluster 4 (n=49)		Cluster 5 (n=26)		F / Chi-Squared	P	Post-hocb
Mean|SD(Percentage)
Age	67.0	6.8	69.2	11.4	66.9	7.2	72.2	8.3	62.9	5.9	66.1	7.6	7.5	0.0	3-2,4,5 2-4
Gender (Male)	28	49%	40%		50%		50%		40%		50%			0.7
Caucasian	50	88%	90%		90%		90%		90%		70%			0.1
Education (Years)	15.2	2.8	12.0	3.1	15.3	2.9	12.9	2.8	14.0	2.2	13.0	2.3	8.1	0.0	2-1,3,5
SES per-capitac	29.6	15.4	21.3	19.9	25.7	21.5	15.2	17.6	16.3	12.8	22.8	20.5	12.2	0.0	2-3,4
Hamilton depression scale (without suicide item) d	2.4	1.9	24.1	6.2	16.3	3.9	18.5	5.9	21.4	3.9	17.9	5.0	13.8	0.0	1-2,3,5 2-4 3-5
IQ	108.6	12.2	95.2	12.5	110.0	14.8	97.4	18.9	105	14.1	97.5	18.2	6.1	0.0	2-1,3,5
Age of Onset of First Depressive Episode	N/A	N/A	55.6	20.5	50.5	19.9	47.4	22.4	37.7	19.1	39.5	22.0	4.3	0.0	4-1,2
Physical Illness Burdend	6.6	3.9	9.5	3.5	8.7	4.4	10.7	3.6	8.2	3.6	8.1	3.1	2.4	0.1
Ideation (Current) d	0.2	0.1	20.2	6.3	9.4	11.4	17.5	10.5	15.6	10.9	11.7	9.9	5.6	0.0	2-1,3,4
Ideation (Lifetime) d	0.2	0.1	21.9	7.2	11.9	12.0	21.1	10.3	22.5	9.0	17.1	12.3	8.8	0.0	2-1,3,4
Anxiety Disorder (Current)	0%		60%		40%		10%		60%		40%			0.0	3-1,2,4
Anxiety Disorder (Lifetime)	1.8%		70%		50%		20%		60%		40%			0.0	1-3,4
Substance Abuse (Current)	0%		20%		10%		10%		10%		20%			0.1
Substance Abuse (Lifetime)	0%		40%		30%		40%		40%		50%			0.7
History of attempt at baseline	NA		76%		32%		60%		51%		50%		13.197	0.0	1-2

^aPlease note that ANOVA was only performed in the depressed participants, HC group is only included as a benchmark.

^bPost-hoc comparisons were done to communicate significant between-cluster differences

^cSES data is reported in thousands.

^dHigher scores indicative of more pathology.