Table 3. Regression models predicting the semantic severity of words describing anxious and sad feelings from the year of publication and Mental Health Index (MHI).

Keywords and model		F test (df)	P value	Year		MHI
				β	P value	β	P value
Fear
	Severity ~ year	1.40 (1, 23,567)	.24	—a	—	—	—
	Severity ~ year + MHI	113.60 (2, 23,566)b	<.001	—	.77	1.93	<.001
Worried
	Severity ~ year	38.10 (1, 4145)	.05	—	—	—	—
	Severity ~ year + MHI	44.12 (2, 4144)	<.001	—	.40	2.48	<.001
Worry
	Severity ~ year	16.72 (1, 11,647)	<.001	.002	<.001	—	—
	Severity ~ year + MHI	114.10 (2, 11,646)	<.001	.001	.01	2.22	<.001
Grief
	Severity ~ year	0.06 (1, 2344)	.80	—	—	—	—
	Severity ~ year + MHI	19.10 (2, 2343)	<.001	—	.60	3.09	<.001
Sad
	Severity ~ year	0.00 (1, 4881)	.99	—	—	—	—
	Severity ~ year + MHI	60.05 (2, 4880)	<.001	—	.59	3.30	<.001
Sadness
	Severity ~ year	0.00 (1, 2643)	.96	—	—	—	—
	Severity ~ year + MHI	5.96 (2, 2642)	.002	—	.79	1.54	<.001
Sorrow
	Severity ~ year	25.17 (1, 6774)	<.001	−.004	<.001	—	—
	Severity ~ year + MHI	235.30 (2, 6773)	<.001	−.004	<.001	6.08	<.001
Unhappy
	Severity ~ year	3.81 (1, 2574)	.05	—	—	—	—
	Severity ~ year + MHI	12.61 (2, 2573)	<.001	−.002	.02	1.64	<.001

^aNot applicable.

^bValues in italics format indicate statistically significant results.