Study objectives: "Sleep quality" is poorly defined yet ubiquitously used by researchers, clinicians and patients. While poor sleep quality is a key feature of insomnia, there are few empirical investigations of sleep quality in insomnia patients. Accordingly, our aim was to investigate the subjective meaning of sleep quality among individuals with insomnia and normal sleepers.
Design: Cross sectional between groups (insomnia vs. good sleeper). Analyses were conducted across three outcome variables: (1) a "Speak Freely" procedure in which participants' descriptions of good and poor sleep quality nights were analysed, (2) a "Sleep Quality Interview" in which participants judged the relative importance of variables included in previous research on sleep quality and (3) a sleep quality diary completed over seven consecutive nights.
Setting: University Department of Psychiatry.
Participants: Individuals with insomnia (n = 25) and normal sleepers (n = 28).
Results: Both the insomnia and normal sleeper groups defined sleep quality by tiredness on waking and throughout the day, feeling rested and restored on waking, and the number of awakenings they experienced in the night. The insomnia group had more requirements for judging sleep to be of good quality.
Conclusion: The meaning of sleep quality among individuals with insomnia and normal sleepers was broadly similar. A comprehensive assessment of a patient's appraisal of their sleep quality may require an assessment of waking and daytime variables.