Table 2

Binary logistic regression analysis of factors associated with negative symptoms in patients with schizophrenia (n=7678)

Factor	Group	Number in sample	Prevalence of two or more negative symptoms (%)	Association with two or more negative symptoms: OR (95% CI), p value
Factor	Group	Number in sample	Prevalence of two or more negative symptoms (%)	Unadjusted		Adjusted model (n=7676)*
Age (years)	16–19	203	27.6	0.35 (0.25 to 0.49)	<0.001	0.50 (0.35 to 0.71)	<0.001
	20–29	1337	52.0	Reference		Reference
	30–39	1775	47.0	0.82 (0.71 to 0.94)	0.006	0.85 (0.73 to 0.99)	0.033
	40–49	1983	42.6	0.69 (0.60 to 0.79)	<0.001	0.71 (0.61 to 0.82)	<0.001
	50–59	1137	37.2	0.55 (0.47 to 0.64)	<0.001	0.56 (0.47 to 0.67)	<0.001
	60–69	654	29.1	0.38 (0.31 to 0.46)	<0.001	0.39 (0.31 to 0.48)	<0.001
	70+	589	18.0	0.20 (0.16 to 0.26)	<0.001	0.22 (0.17 to 0.28)	<0.001
Gender	Male	4592	45.3	Reference		Reference
Gender	Female	3084	34.7	0.64 (0.59 to 0.71)	<0.001	0.77 (0.70 to 0.85)	<0.001
Marital status (most recent)	Single	5795	44.6	Reference		Reference
	Married/cohabiting	785	31.6	0.57 (0.49 to 0.67)	<0.001	0.76 (0.64 to 0.90)	0.002
	Divorced/separated	776	33.4	0.62 (0.53 to 0.73)	<0.001	0.85 (0.71 to 1.00)	0.054
	Widowed	208	21.2	0.33 (0.24 to 0.47)	<0.001	0.77 (0.53 to 1.12)	0.178
Employment (most recent)	Unemployed	4956	47.9	Reference		Reference
	Employed	341	39.6	0.71 (0.57 to 0.89)	0.003	0.68 (0.54 to 0.86)	0.001
	In education	311	39.6	0.71 (0.56 to 0.90)	0.004	0.81 (0.63 to 1.03)	0.089
	Retired	7	14.3	0.18 (0.02 to 1.51)	0.114	0.40 (0.04 to 3.52)	0.405
ADL impairment	Absent	4700	41.9	Reference		Reference
ADL impairment	Present	2283	46.3	1.20 (1.08 to 1.32)	<0.001	1.35 (1.21 to 1.52)	<0.001
Social impairment	Absent	4432	42.7	Reference		Reference
Social impairment	Present	2533	44.4	1.07 (0.97 to 1.18)	0.158	0.94 (0.84 to 1.05)	0.240
Delusions/hallucinations	Absent	3904	41.9	Reference		Reference
Delusions/hallucinations	Present	3077	45.0	1.14 (1.03 to 1.25)	0.009	1.19 (1.07 to 1.31)	0.001
Depression	Absent	4976	45.2	Reference		Reference
Depression	Present	2014	38.8	0.77 (0.69 to 0.85)	<0.001	0.74 (0.66 to 0.82)	<0.001

*Results adjusted for all the factors reported in this table; two cases with no recorded data on gender were dropped.
ADL, activities of daily living.