How much does not having advanced notice of your daily or weekly schedule affect your mental and physical health? For those who work in the retail sector, the answer is quite a bit.

Kristen Harknett, an adjunct associate professor in the Department of Sociology in the School of Arts & Sciences, studies economic influences on families. Along with Daniel Schneider from the University of California, Berkeley, she decided to look at scheduling practices for eight of the largest retailers in the United States, focusing on how much lead time workers get before they have to clock in and how much their schedules change daily and weekly.

The researchers published their results in a new working paper from the Washington Center for Equitable Growth.

“If you have more advanced notice of your work schedule, then you’re less likely to report psychological distress, you’re less likely to report poor health, you’re less likely to report poor sleep quality,” Harknett says. “Simply having at least two weeks’ advanced notice is associated with all these benefits.”

To draw this conclusion, the sociologists built their own dataset after discovering that none available considered the intersection of health and scheduling practices they sought. Using an online questionnaire they created as well as targeted advertising, they recruited nearly 6,000 18- to 50-year-old participants via Facebook, concentrating on people who worked for one of the selected retailers.

After controlling for factors such as low wages and overall income, they confirmed what anecdotal evidence to date has shown about variable schedules: These practices cause harm and difficulty, particularly for working parents, who lose any ability to plan ahead.

“You can’t have a second job, you can’t go to school, you can’t have a regular child-care arrangement. Everything has to be arranged at the last minute,” Harknett says. “We think this will have implications for children, too.”

The researchers hypothesize that technology has had a hand in taking these practices to the extreme, allowing employers to use software to add or cancel shifts last minute without accounting for the human element. Companies, and perhaps more importantly cities, have begun to understand the downsides to this, and have enacted laws around scheduling.

San Francisco and Seattle have already passed legislation, and San Jose, Calif., Washington, D.C., and New York City are considering it. Though each city’s statute looks slightly different, they all address aspects of scheduling aimed at improving the situation for employees.

“There’s a stark difference between people who have low wages but their schedules are stable, and their counterparts who have the same types of jobs and wages but crazy schedules that bounce all around,” Harknett says.