Abstract. Objectives: To determine the shift lengths currently worked by emergency medicine (EM) residents and their shift length preferences, and to determine factors associated with EM residents' subjective tolerance of shiftwork. Methods: A survey was sent to EM-2 through EM-4 allopathic EM residents in May 1996. This questionnaire assessed the residents' shift length worked, shift length preferences, night shift schedules, and self-reported ability to overcome drowsiness, sleep flexibility, and morningness-eveningness tendencies. When providing shift length preferences, the residents were asked to assume a constant total number of hours scheduled per month. Results: Seventy-eight programs participated, and 62% of 1,554 eligible residents returned usable surveys. Current shift lengths worked were 8 hours (12%), 10 hours (13%), 12 hours (37%), combinations of 8-hour, 10-hour, or 12-hour (34%) shifts, and other combinations (4%). Seventy-three percent of the respondents indicated that they preferred to work 8-hour or 10-hour shifts, and only 21% preferred a 12-hour shift. Shiftwork tolerance was recorded as: not well at all (2%), not very well (14%), fairly well (70%), and very well (14%). The EM residents' eveningness preference, ability to overcome drowsiness, sleep flexibility, younger age, and having no children at home were all associated with greater shiftwork tolerance. Conclusions: Emergency medicine residents generally tolerate shiftwork well and prefer 8-hour or 10-hour shift lengths compared with 12-hour shift lengths. Emergency medicine residencies with 12-hour shifts should consider changing residents' shifts to shorter shifts. Key words: work schedule tolerance; shiftwork; morningness-eveningness; circadian rhythms; postgraduate medical education; residents. ACADEMIC EMERGENCY MED-ICINE 2000; 7:670-673 S HIFTWORK has been identified as a major source of attrition in emergency medicine (EM).1-3 Multiple factors have been identified that affect shiftwork tolerance. These include the morningness-eveningness preferences, flexibility of sleeping patterns, and ability to overcome drowsiness.4,5 Age, gender, and whether children are present in the home have also been associated with tolerance. 6 To our knowledge, there are currently no data describing EM resident tolerance of shiftwork. Working different length shifts is common in EM. Two prior studies indicate that practicing emergency physicians (EPs) and EM residency faculty prefer working shorter shifts. 7,8 For EM residents, we know of no information describing their lengths of shifts worked or their preferences.The objective of this study was to determine the shift lengths currently worked by EM residents and their shift length preferences. This study also determined the association of various factors with EM residents' subjective tolerance of shiftwork.
METHODSStudy Design. The self-administered survey was distributed to eligible EM residents. The medical center's IRB approved the study protocol.