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Published on: August 8, 2019
Who Works Non-Day Shifts? An Investigation of Population and Within-Cohort Trends
Gawon Cho1, Joshua Chodosh, Jennifer Hill
1From the Department Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut (G.C.); Department of Social and Behavioral Sciences, School of Global Public Health, New York University, New York, New York (G.C., V.W.C.); Grossman School of Medicine, New York University, New York, New York (J.C., V.W.C.); VA New York Harbor Healthcare System, New York, New York (J.C.); and Department of Applied Statistics, Social Science, and Humanities, Steinhardt School of Culture, Education, and Human Development, New York University, New York, New York (J.H.).
Objectives:
We examined trends in the socioeconomic distribution of work schedules from 1990s to 2010s and how early adulthood disadvantages are associated work schedules over working age.
Methods:
In a representative sample of US workers (Midlife in the U.S. Study (MIDUS), N = 3328), we calculated recycled predictions of day, evening, night, and long shift prevalence associated with time period. Logistic regression was used to analyze the association of non-day shifts with age and its variations by early adulthood disadvantage in US baby boomers (National Longitudinal Survey of Youth 79 (NLSY79), N = 10,293).
Results:
In U.S. workers, between 1990s-2010s, evening shifts increased in adults without college education and night shifts increased in the lowest income quartile. Day shifts decreased in both groups. In US baby boomers, the odds of working non-day shifts decreased with age. However, being Black, not attending college, and poverty were associated with higher odds of non-day shiftwork throughout working age.
Conclusions:
Evening and night shifts may have replaced day shifts in socioeconomically disadvantaged populations between 1990s-2010s. Early adulthood disadvantages may have sustained effects on work schedules.
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