Abstract
STUDY OBJECTIVES: The current study was designed to examine if improvements in high school graduation and attendance rates persist 4 years after start times later than 8:30 am. Socioeconomic status and race were accounted for in the graduation analysis. METHODS: School-wide attendance and graduation records (n = 28 schools) from 1999-2017 were analyzed in August of 2021 using a repeated-measures analysis of variance at 5 points in time, 1 year predelay and 4 consecutive years postdelay start times. RESULTS: Graduation rates for students in grade 12 (n > 47,000) after postdelay year 4 increased from 80% to 90% (P < .001) and attendance rates in grades 9-12 (n > 80,000) improved from 90% to 93% (P = .012). CONCLUSIONS: Attendance and graduation rates for all students improved after 4 years following a delayed start. Economically disadvantaged students and Black students showed significant changes in graduation rates postdelay year 4 and White students significantly improved postdelay years 2, 3, and 4. Adolescent students, especially economically and racially disadvantaged students, have a vulnerability for obtaining adequate sleep. Delaying high school start times is a cost-effective intervention that could promote sufficient sleep and boost graduation and attendance rates. CITATION: McKeever PM, Dodd R, O'Sullivan DM. Delayed high school start times and graduation and attendance rates over 4 years: the impact of race and socioeconomics. J Clin Sleep Med. 2022;18(11):2537-2543.