Table 5.

Age and gender differences in scores on the simplified Japanese version of the Athens Insomnia Scale (AIS‐SJ) and its subscales (n = 50,547)

Scales	Younger (aged 16–64 years)		Older (aged 65 years or older)
	Men	Women	Men	Women
Total (0–8)	2.79 (2.42)	3.19 (2.41)	2.82 (3.39)	3.49 (2.51)
Nocturnal (0–5)	1.77 (1.61)	1.96 (1.62)	1.84 (1.61)	2.29 (1.71)
Daytime (0–3)	1.02 (1.11)	1.23 (1.12)	0.98 (1.08)	1.20 (1.15)

Means (standard deviations) were shown in each cell. As a result of two‐way analyses of variance (with age group and gender as factors), interaction terms for AIS‐SJ and Nocturnal scores were significant (F(1, 50,543) = 32.06, p < 0.01, partial η² = 0.00063; F(1, 50,543) = 64.28, p < 0.01, partial η² = 0.00127). Main effects of age and gender for Daytime score were significant (F(1, 50,543) = 7.86, p < 0.01, partial η² = 0.00016; F(1, 50,543) = 371.94, p < 0.01, partial η² = 0.00731).