Summary of findings 1. Summary of findings table ‐ Light therapy compared to usual care for sleep disturbances in people with dementia.

Light therapy compared to usual care for sleep disturbances in people with dementia
Patient or population: sleep disturbances in people with dementia Setting: nursing home Intervention: light therapy Comparison: usual care
Outcomes	Anticipated absolute effects* (95% CI)		Relative effect (95% CI)	№ of participants (studies)	Certainty of the evidence (GRADE)	Comments
	Risk with usual care	Risk with light therapy
Total nocturnal sleep time (minutes)	The mean total nocturnal sleep time in the control group was 512 minutes (Dowling 2005), 496 minutes (Figueiro 2019), 430 minutes (Fontana Gasio 2003), and 248 minutes (Sloane 2014). Total nocturnal sleep time between groups was 33 minutes lower (103.54 lower to 37.54 higher) in Dowling 2005, 20.40 minutes lower (63.29 lower to 22.49 higher) in Figueiro 2019, 110.00 minutes higher (19.36 higher to 200.64 higher) in Fontana Gasio 2003, and there was no clear difference in Sloane 2014 (0.23 minutes higher, 12.75 lower to 12.28 higher).			82 (4 RCTs)	⊕⊝⊝⊝ Very lowa,b,c	2 studies found a difference in favour of the control group (Dowling 2005; Figueiro 2019). Fontana Gasio 2003 found differences in favour of the intervention. Sloane 2015 found no clear difference between groups.
Consolidated sleep ‐ not measured	‐	‐	‐	‐	‐	‐
Sleep efficiency	The mean sleep efficiency in the control group was 71.14% (Dowling 2005), 85.43% (Figueiro 2019), 59.9% (Fontana Gasio 2003), 78.1% (McCurry 2011), 90.84% (Nowak 2008), and 68.9% (Sloane 2014). 1 study reported no data. Sleep efficiency between groups was 4.50% lower (14.34 lower to 5.34 higher) in Dowling 2005, 2.21% lower (5.17 lower to 0.75 higher) in Figueiro 2019, 16.60% higher (6.49 higher to 26.71 higher) in Fontana Gasio 2003, 6.20% higher (0.04 lower to 12.44 higher) in McCurry 2011, and 5.60% higher (0.47 higher to 10.73 higher) in Nowak 2008. 2 studies found no difference between groups, 0% (3.45 lower to 3.45 higher) in Sloane 2014, Ancoli‐Israel 2003 reported no data.			133 (7 RCTs)	⊕⊝⊝⊝ Very lowa,b,c	Dowling 2005 reported differences between groups in favour of the control group using actigraphy after 11 weeks. 3 studies found small improvements in the intervention group after 10 weeks, and 2 months and 2 weeks (Fontana Gasio 2003; McCurry 2011; Nowak 2008). 2 studies found no difference between groups after 15 days and 6 weeks (Ancoli‐Israel 2003; Sloane 2014)
Total wake time at night (minutes)	The mean night‐time total wake time in the control group was 207 minutes (Dowling 2005) and 123 minutes (McCurry 2011), 1 study did not offer this information. Night‐time total wake time between groups was 32.00 minutes higher (38.54 lower to 102.54 higher) in Dowling 2005 and 39.00 minutes lower (74.40 lower to 3.60 lower) in McCurry 2011. 1 study found no difference between groups, but no further information was reported.			205 (3 RCTs)	⊕⊝⊝⊝ Very lowa,b,c	Dowling 2005 reported a small improvement in the control group and McCurry 2011 found a small improvement in the intervention group using actigraphy after 11 weeks and 2 months. Ancoli‐Israel 2002 found no differences between groups after 15 days.
Number of nocturnal awakenings	The mean night‐time number of awakenings in the control group was 37.99 (Dowling 2005), 14.9 (Sloane 2014), 17.6 (McCurry 2011), and 4.6 (Nowak 2008). Night‐time number of awakenings for light therapy was 4.89 higher (3.31 lower to 13.09 higher) in Dowling 2005, 2.90 lower (7.09 lower to 1.29 higher) in McCurry 2011, and 2.31 lower (4.17 lower to 0.45 lower) in Nowak 2008. Sloane 2014 found no clear difference between groups (0.81 lower, 2.64 lower to 1.03 higher).			136 (4 RCTs)	⊕⊝⊝⊝ Very lowa,b,c	Dowling 2005 reported small improvements in the control group after 11 weeks and 2 studies reported a small improvement in the intervention group after 2 weeks and 2 months (McCurry 2011; Nowak 2008). Sloane 2015 found no difference between groups.
Sleep onset latency	The mean sleep onset latency in the control group was 12.32 minutes (Figueiro 2019), 1 minute (Fontana Gasio 2003), and 24 minutes (Sloane 2015). Sleep onset latency between groups was 6.05 minutes higher (0.60 lower to 12.70 higher) in Figueiro 2019, 1.02 minutes lower (3.34 lower to 1.30 higher) in Fontana Gasio 2003, and 3.72 minutes lower (9.54 lower to 2.10 higher) in Sloane 2015.			(3 RCTs)	⊕⊕⊝⊝ Lowc,d	3 studies reported no clear differences between groups after 3, 4, and 6 weeks (Figueiro 2019; Fontana Gasio 2003; Sloane 2015).
Adverse events	None of the studies reported any unexpected or serious adverse events			318 (7 RCTs)	⊕⊝⊝⊝ Very lowa,b,c	‐
*The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval
GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.
See interactive version of this table: https://gdt.gradepro.org/presentations/#/isof/isof_question_revman_web_424365942749483426.

^a Downgraded one level for risk of bias: unclear risk of bias in several studies; high risk of bias in blinding participants and personnel in one study (McCurry 2011).
^b Downgraded one level for inconsistency: inconsistent results between studies.
^c Downgraded one level for imprecision: wide confidence intervals in individual studies.
^d Downgraded one level for risk of bias: unclear risk of selection bias in all studies, high risk of reporting bias in one study (Figueiro 2019).