Sleep health, its intraindividuality, and perceived stress in college students during the COVID-19 pandemic.

To describe the changes in sleep health domains and examine the associations between the repeated measures and intraindividual variability (IIV) of these domains and perceived stress. : A diverse racial and ethnic group of first-year college students ( = 23, 78.3% female, aged 17-18) attending in-person classes during the COVID-19 pandemic. : Sleep health domains were determined using 7-day wrist actigraph and daily sleep diaries, and perceived stress scale was completed at 1-month intervals across 3 months. : Sleep timing, regularity, and alertness during daytime demonstrated statistically significant changes between three timepoints. Greater stress was associated with more irregularity ( = 2.25 [.87-3.62],  < .001), more dissatisfaction in sleep ( = .04 [.02-.19],  < .01), alertness during daytime ( = .18 [.05-.31],  < .001), and greater IIV (ie, fluctuations) in sleep satisfaction ( = .083 [.02, .15],  < .01). : These findings offer insights for future researchers to facilitate intervention development to promote mental and sleep health among college students.