摘要：Objectives. We compared work and lifestyle activities for workers who work in 1 job with those who work in multiple jobs during a 1-week period. Methods. We used information from the 2003–2011 American Time Use Survey to classify workers into 6 work groups based on whether they were a single (SJH) or multiple (MJH) job holder and whether they worked their primary, other, multiple, or no job on the diary day. Results. The MJHs often worked 2 part-time jobs (20%), long weekly hours (27% worked 60+ hours), and on weekends . The MJHs working multiple jobs on the diary day averaged more than 2 additional work hours (2.25 weekday, 2.75 weekend day; P < .05), odd hours (more often between 5 pm and 7 am ), with more work travel time (10 minutes weekday, 9 minutes weekend day; P < .05) and less sleep (–45 minutes weekday, −62 minutes weekend day; P < .05) and time for other household ( P < .05) and leisure ( P < .05) activities than SJHs. Conclusions . Because of long work hours, long daily commutes, multiple shifts, and less sleep and leisure time, MJHs may be at heightened risk of fatigue and injury. Over the past 5 decades, there have been revolutionary changes in the organization and nature of work in the United States. The implications of those changes on the health and safety of workers are discussed in a report that describes a national agenda for research on this topic 1 with a focus on a shift in the organization of work centered on employer-restructuring activities. For instance, contracting out specific work tasks or flexible staffing are examples of widespread changes adopted by employers, especially during recent economic downturns. 2–4 This can result in job instability, reduced work hours, and a reduction in benefits or pay, requiring workers to incorporate lifestyle changes to maintain their standard of living. One potential change would be to seek additional work, possibly a second job, for supplemental income. 2,3 Alternatively, some workers moonlight to enhance entrepreneurial opportunities or pursue a hobby or special interest. 5–7 In 2012, 8.5% of the employed workforce in the United States worked in more than 1 job during a 1-week period. 8 In a previous study 9 in which we used data from the US National Health Interview Survey (NHIS), we found that workers with more than 1 job in a 1-week period (multiple jobholders [MJHs]) had a higher risk of injury than single job holders (SJHs). This finding was consistent for both work and nonwork injuries; the rate remained elevated even after we controlled for hours worked. Two other recent studies in the United States have also shown elevated risk of injury for MJHs: an elevated rate of work-related fatalities for MJHs was reported in Kentucky, 10 and an elevated rate and severity of injury was reported for adolescent MJHs in Wisconsin. 11 There are several potential reasons why work in multiple jobs may be associated with an increased risk of injury, including the possibility of fatigue as a result of extra hours worked, less time sleeping, and working odd shifts to fit multiple jobs into a work week. 12–15 Basner et al. 16 used American Time Use Survey (ATUS) data and found that more work time resulted in less sleep time and that people working in multiple jobs worked longer and slept less to earn the same amount of money as people with 1 job. We used ATUS data to further explore similarities and differences in the components of work and lifestyle activities for workers who work in only 1 job compared with workers who work in multiple jobs during a 1-week period. We compared activities of daily living between MJHs and SJHs and looked discretely at how activities change (duration and time of day) over the course of a 24-hour period if a worker is engaged in work (in 1 or multiple jobs) or not during the day, testing the hypothesis that MJHs have as much time for rest and leisure as SJHs.
