Table 2 Neuropsychiatric inventory measure of sleep disturbance (NPI)
Frequency score | Severity score | ||||
|---|---|---|---|---|---|
1 | Occasionally | Less than once per week | 1 | Mild | Night-time behaviours occur but they are not particularly disruptive |
2 | Often | About once per week | 2 | Moderate | Night-time behaviours occur and disturb the participant and the sleep of the caregiver, more than one type of night-time behaviour may be present |
3 | Frequently | Several times per week but less than every day | 3 | Marked | Night-time behaviours occur; several types of night-time behaviour may be present; the participant is very distressed during the night and the caregiver’s sleep is markedly disturbed |
4 | Very frequently | Once or more per day | |||