Table 3.

Spearman correlations between major depressive disorder symptom severity at baseline and at episode recurrence at 2-, 4-, 6- and 9-year follow-up^a

IDS symptom		2 years (n = 302)	4 years (n = 229)	6 years (n = 190)	9 years (n = 154)
Core symptoms
Depressed mood	Baseline	0.34	0.34	0.28	0.32
	2 years	−	0.43	0.29	0.31
	4 years	−	−	0.25	0.26
	6 years	−	−	−	0.56
Anhedonia	Baseline	0.39	0.39	0.36	0.26
	2 years	−	0.45	0.45	0.24
	4 years	−	−	0.45	0.44
	6 years	−	−	−	0.58
Non-core symptoms
Fatigue/loss of energy	Baseline	0.39	0.32	0.28	0.21
	2 years	−	0.45	0.41	0.26
	4 years	−	−	0.51	0.32
	6 years	−	−	−	0.40
Appetite/weight change
Appetite increase	Baseline	0.55	0.47	0.31	0.49
	2 years	−	0.60	0.43	0.44
	4 years	−	−	0.46	0.46
	6 years	−	−	−	0.42
Appetite decrease	Baseline	0.42	0.28	0.28	0.32
	2 years	−	0.42	0.23	0.16
	4 years	−	−	0.17	0.07
	6 years	−	−	−	0.45
Weight increase	Baseline	0.25	0.23	.27	0.30
	2 years	−	0.34	0.35	0.33
	4 years	−	−	0.44	0.26
	6 years	−	−	−	0.42
Weight decrease	Baseline	0.24	0.09	0.20	0.13
	2 years	−	0.03	0.36	0.07
	4 years	−	−	0.28	0.33
	6 years	−	−	−	0.15
Sleep disturbance
Insomnia	Baseline	0.56	0.59	0.59	0.60
	2 years	−	0.66	0.69	0.55
	4 years	−	−	0.64	0.56
	6 years	−	−	−	0.65
Hypersomnia	Baseline	0.48	0.53	0.50	0.35
	2 years	−	0.51	0.55	0.35
	4 years	−	−	0.60	0.47
	6 years	−	−	−	0.57
Psychomotor disturbance
Psychomotor agitation	Baseline	0.48	0.21	0.43	0.26
	2 years	−	0.37	0.56	0.28
	4 years	−	−	0.46	0.31
	6 years	−	−	−	0.31
Psychomotor retardation	Baseline	0.41	0.42	0.29	0.37
	2 years	−	0.41	0.51	0.46
	4 years	−	.	0.59	0.42
	6 years	−	−	−	0.45
Worthlessness/guilt	Baseline	0.40	0.37	0.34	0.31
	2 years	−	0.40	0.42	0.38
	4 years	−	−	0.47	0.47
	6 years	−	−	−	0.45
Concentration difficulties	Baseline	0.40	0.26	0.24	0.28
	2 years	−	0.29	0.24	0.10
	4 years	−	−	0.52	0.17
	6 years	−	−	−	0.45
Suicidal ideation	Baseline	0.46	0.48	0.36	0.48
	2 years	−	0.49	0.53	0.39
	4 years	−	−	0.39	0.45
	6 years	−	−	−	0.55

IDS, Inventory of Depressive Symptomatology

^a.Interpretation of correlation coefficients based on r = 0.50 indicating large, r = 0.30 medium, and r = 0.10 small correlations.²³ Significant correlations based on P < 0.005 are indicated in bold.