Dowling 2008.

Methods	RCT, 3 parallel treatment groups
Participants	Number of participants: 50 completed study (33 contributed data to this review) Country: USA Setting: 2 large long‐term care facilities Diagnosis: probable AD (NINCDS‐ADRDA criteria) Sleep‐related inclusion criteria: rest‐activity rhythm disruptions including insomnia, frequent night‐time awakenings, wandering at night, unusually early morning awakenings, sundowning, excessive daytime sleepiness. Gender: 43 women, 7 men Age: 86 ± 8 years (range 60 to 100) Severity of dementia: MMSE 9.3 ± 7.9, no significant difference between groups
Interventions	Duration of treatment: 10 weeks Treatment group 1 (15 participants): 5 mg melatonin in the evening combined with bright light exposure in the morning (light for 1 h, > 2500 lux, at gaze height, 5 days a week) Treatment group 2 (18 participants): lactose placebo in the evening combined with bright light exposure in the morning Both treatment groups: Route of administration: oral Time of administration: 5 to 6 PM (bedtime at 8 PM) Additional treatment groups, not included in review: Usual light only, no drug or placebo, 17 participants
Outcomes	All outcomes measured using actigraphy over a 108‐h monitoring period (Monday 8 PM to Saturday 8 AM) Outcome time points: baseline and end of treatment (10 weeks) Sleep/wake: Night‐time outcomes sleep time number of awakenings sleep bout duration wake bout duration Daytime outcomes sleep time sleep bout duration wake bout duration number of sleep bouts day total activity Subsidiary measures: Additional circadian outcomes were computed to quantify each participant’s 24‐h rest‐activity rhythm, and this was then used to assess: interdaily stability: the degree of resemblance between activity patterns of individual days intradaily variability: the fragmentation of periods of rest and activity L5: sequence of the 5 least‐active hours in the 24‐h average activity profile. Average activity during L5 provides an indication of trough or nadir of the rhythm (i.e. regularity and restfulness of sleep periods) M10: sequence of the 10 most‐active hours in the 24‐h average activity profile. Average activity during M10 provides an indication of the peak of the rhythm (how active and regular the activity (wake) periods are) amplitude: the difference between the most‐active 10‐h period and the least‐active 5‐h period in an average 24‐h pattern relative amplitude: reflects the normalized difference between the most‐active 10‐h period and the least active 5‐h period in an average 24‐h pattern
Notes	Placebo and melatonin groups did not differ significantly in bright light received No mention was made of adverse events Non‐commercial funding
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Subjects were randomly assigned to one of the three groups." No information on randomisation method provided
Allocation concealment (selection bias)	Unclear risk	No information provided
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"The University of California, San Francisco Drug Product Services Laboratory provided melatonin (5 mg) and identically appearing lactose placebo capsules." "Study staff, nursing home staff, and subjects were all blinded to melatonin treatment group assignment."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"Study staff . . . were all blinded to melatonin treatment group assignment." Outcomes were actigraphy data (objective)
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	"Fifty subjects completed the study." No mention of how many participants were randomised, so unclear if there were any dropouts. Those completing the study were reported to have tolerated the procedures well. There was a target of 108 h of data at each time point. Valid data at baseline: mean 105 h (range 75 to 108); valid data at the end of intervention: mean 107 h (range 90 to 108); "no significant differences between the groups."
Selective reporting (reporting bias)	Low risk	Results reported for all listed outcome measures
Other bias	Low risk	None identified