Table 3. Pittsburgh Sleep Quality Index (PSQI) (N=33).

	Study population	Healthy controlsa
Sleep indicators	Mean±s.e.	Mean±s.e.
Sleep quality	1.7±0.18	0.35±0.07
Sleep latency	1.6±0.22	0.56±0.10
Sleep duration	1.3±0.22	0.29±0.07
Sleep efficiency	1.3±0.24	0.1±0.04
Sleep disturbance	2.3±0.12	1.0±0.05
Sleep medication	0.9±0.19	0.04±0.04
Daytime dysfunction	1.5±0.27	0.35±0.07
Global sleep quality score	10.6±0.95	2.67±0.23

^aOwen et al (1999) 26, 1649–1651.