Table 3.

Accuracy of individual loneliness items in classifying mental health problems.

“How often do you feel alone?”		Age-18 Sample		Age-38 Sample
	Response	Sensitivity	Specificity	Sensitivity	Specificity
Depression	Hardly ever	1.00	0.00	1.00	0.00
	Some of the time	0.60	0.75	0.63	0.75
	Often	0.20	0.96	0.17	0.98
Anxiety	Hardly ever	1.00	0.00	1.00	0.00
	Some of the time	0.70	0.71	0.70	0.71
	Often	0.25	0.95	0.22	0.97
Self-harm/suicide attempt	Hardly ever	1.00	0.00	1.00	0.00
	Some of the time	0.66	0.74	0.45	0.71
	Often	0.24	0.96	0.11	0.97
“How often have you felt lonely in the past month?”		Age-18 sample		Age-38 sample
	Response	Sensitivity	Specificity	Sensitivity	Specificity
Depression	Hardly ever	1.00	0.00	1.00	0.00
	Some of the time	0.61	0.77	0.35	0.93
	Often	0.25	0.97	0.12	0.99
Anxiety	Hardly ever	1.00	0.00	1.00	0.00
	Some of the time	0.68	0.72	0.41	0.90
	Often	0.29	0.94	0.15	0.98
Self-harm/suicide attempt	Hardly ever	1.00	0.00	1.00	0.00
	Some of the time	0.64	0.75	0.29	0.91
	Often	0.27	0.96	0.10	0.98