Evaluation of the impact of fibromyalgia on patients' sleep and the content validity of two sleep scales

Table 2 MOS Sleep Scale Subscales and Scoring^a

Subscale	Number of Items	Brief Description (Item Number on Scale)	Scoring Range^b
Sleep disturbance	4	Trouble falling asleep (7); time to fall asleep (1); restless sleep (3); awaken during sleep (8)	0 to 100
Snoring	1	Snore during sleep (10)	0 to 100
Awaken short of breath or with headache	1	Awaken short of breath or with headache (5)	0 to 100
Quantity of sleep	1	Quantity of sleep (2)	0 to 24
Optimal sleep	1	"Optimal" sleep (2)^c	0 or 1^c
Sleep adequacy	2	Enough sleep to feel rested (4); amount of sleep needed (12)	0 to 100
Somnolence	3	Feel drowsy during day (6); trouble staying awake during day (9); take naps (11)	0 to 100
Sleep Problem Index II^d	9	Trouble falling asleep (7); time to fall asleep (1); restless sleep (3); awaken during sleep (8); awaken short of breath or with headache (5); enough sleep to feel rested (4); amount of sleep needed (12); feel drowsy during day (6); trouble staying awake during day (9)	0 to 100

^a See Additional file 1 for full MOS-Sleep Scale.
^b Higher scores indicate more of the concept being measured (e.g., higher Sleep Disturbance scores indicate greater sleep disturbances). Quantity of Sleep scores are the patient-reported number of hours of sleep per night.
^c If the patient reports 7 or 8 hours of sleep per night, the Optimal Sleep score is 1; otherwise the Optimal Sleep score is 0.
^d Nine-item summary score, sometimes referred to as Sleep Index II. The 6-item summary scale (Sleep Index I) includes the same items, with the exception of item 1 (time to fall asleep), item 3 (restless sleep), and item 6 (feel drowsy during the day), and was developed as a briefer alternative to the 9-item index.

ISSN: 1477-7525