Table 1.

Nine homogeneity of variances tests across 9-year intervals to assess increases in the variance of GHQ-12 scores among 16–24 years between 1991 and 2008 (BHPS)

Comparison A–B	Men			Women
	Standard deviation		Ha: ratio <1	Standard deviation		Ha: ratio <1
	A	B	p values	A	B	p values
1991–2000	4.14	4.77	<0.005	5.11	5.82	<0.005
1992–2001	4.31	4.88	<0.005	4.91	5.61	<0.005
1993–2002	4.80	5.17	0.04	5.03	5.91	<0.005
1994–2003	4.58	5.05	0.01	5.34	5.69	0.07
1995–2004	4.72	4.75	0.44	5.44	6.16	<0.005
1996–2005	4.85	5.35	0.01	5.70	6.42	<0.005
1997–2006	4.91	4.96	0.40	5.64	5.91	0.13
1998–2007	4.85	5.27	0.03	5.39	6.34	<0.005
1999–2008	4.87	5.08	0.16	5.12	6.30	<0.005