The Effects of Light Therapy on Sleep, Depression, Neuropsychiatric Behaviors, and Cognition Among People Living With Dementia: A Meta-Analysis of Randomized Controlled Trials

•What is the primary question addressed by this study?The effects of light therapy on sleep, depression, neuropsychiatric behaviors, and cognition among people living with dementia is still contested.•What is the main finding of this study?This meta-analysis demonstrates that light therapy is effective in improving sleep, cognition, and decreasing depression and neuropsychiatric behaviors for PLWD. Administering light therapy twice a day is more advantageous and effective in improving depression and neuropsychiatric behaviors compared to once a day.•What is the meaning of the finding?Light therapy is a low-cost, safe, and nonpharmacological intervention that may be used to improve sleep, depression, neuropsychiatric behaviors, and cognition for PLWD.