Overtime and health among salaried employees

When this article was written, there had been little research on the effects of overtime. There were some links to negative outcomes:


Increased exposure to a moderately toxic environment or hazardous activity clearly increase risks; one could presume that increased exposure to a stressful environment would bring about more stress-related problems (e.g. heart issues, blood pressure, and such). More exposure, rather than any psychological or role-conflict problems, could explain all of these findings. Could there be more to it than lack of time for health care and sleep, and more exposure to stress and workplace toxins?

Fottler and Schaller (1975) studied 1,400 hourly workers, and found that younger workers, men, and married workers under 30 accepted more overtime. Shepherd and Walker (1958) correlated overtime with family responsibilities — but only among workers with lower wages.

For our study, we looked at a population of around 200 full-time, non-union college staff workers, and garnered 96 surveys were returned, for a response rate of 48%. Almost all had a college degree; 68 (71%) had no children; and about half were women.  The mean age was 38, and the mean salary was about $33,000 in 1994. We sent the surveys to each person at their office with cover letters from the consultant and the chair of a staff committee, and a pre-stamped envelope for private replies.

Our overtime question was quite simple — “How often do you work overtime? ___ (hours per day)? ___ (days per week)? ___ (weekends per month)?” The correlations between these were moderate, so we concluded that each one taps a different aspect of overtime and should be considered separately. This does have implications for future research. (Overtime is defined as “hours worked beyond the normal schedule” (Baird & Beccia, 1980, p. 557), so it can be applied to salaried employees.)

Table 1: Correlations of overtime measures
Hours/Day Days/Week Weekends/Month
Hours / Day 1.00 .65** .38**
Days / Week .65** 1.00 .34*
Grade level .38* .46** .48**
Salary .31* .33* .17
Age .08 .22 .07
Tenure .05 – .07 .18
* p ≤ .05     ** p ≤ .01

Medical problems. We measured this with a list of medical benefits respondents had recently used — vision care, sick leave, and disability leave. Vision care was included because working long hours with computer equipment may lead to damage to the eye’s focusing mechanism (Researchers, 1987; Study, 1988).

Reasons for working overtime. A list of possible reasons for working overtime were assembled by a group including the consultant and members of the professional staff; we also provided an “other” category, used only by two people. We also asked for age, grade level, salary, and years worked at the college.

What we learned

One quarter of the respondents reported working no overtime hours per day; over one half worked one hour per day or more. 67% worked overtime two or more days per week. Over half of the respondents (52%) reported working at least one weekend per month.

Medical benefits. The sample was divided into thirds, based on overtime worked (using each of the measures); the benefits usage of the top third was compared to that of the bottom third. No significant differences were found, using chi-square tests. The sample was then divided into halves, based on overtime worked. The top half did not use medical benefits more than the bottom half, again.  Similar results were obtained when the sample was divided into those who had and who had not worked overtime. It’s possible our measures were not sensitive enough; or it takes more overtime than our sample, in a more hazardous workplace, to get any effect.

Seniority. All three measures of overtime were positively correlated with grade level; only days and hours were related to salary (see Table 1). No measure of overtime was related to age or length of time at the college.


Each measure of overtime was positively correlated with grade level, providing some support for the idea that intrinsic motivation may cause overtime, if one assumes that jobs at higher grade levels are more intrinsically motivating. The organization may also demand more work of people in higher grade levels.

There was no significant correlation between overtime and age or salary were also checked.

Research on overtime among hourly employees may not be applicable to exempt employees, perhaps due to workplace hazards, or because exempt employees’ salaries are high enough — in this institution — that they need not work extra hours merely for economic reasons (following Shepherd & Walker, 1958). The relationship between overtime and perceived financial rewards may also be weak, though this may also be an organizational artifact. In this organization, also, an employee may receive “comp time” (compensatory time off for overtime worked).

Reasons for working overtime

This was completed by only 78 people (81%), 20 of whom cited multiple reasons. The most common reason cited was a heavy workload (see below), which in some cases was seasonal. The only reasons for working overtime which were not related to the amount of work at hand were avoiding interruptions and supervisor requests.

Heavy workload: 55 cases
Understaffing: 21 cases
Want to avoid interruptions: 17 cases
Requested by supervisor: 2 cases
Other: 4 cases
Missing/no response: 18 cases

Possibilities for future research

More theory and research on overtime would be useful, for both exempt and for non-exempt employees. The distinction between long hours and overtime has not been examined; for example, are the health problems associated with overtime in the past due to overtime itself, or simply to longer hours? Is there a difference between a standard 40 hour work week and a 35 hour work week with 5 hours of overtime — in other words, is there an essential psychological component of overtime which may be distinguished with the effects of working long hours? If there is no practical difference, then the concept of overtime is unnecessary.

The findings suggest that there may be differences in the effects of overtime in terms of hours per day, days per week, and weekends per month. The reasons why these types of overtime should have different effects may be explored. One may suggest, for example, that weekend work may have more of a psychological effect, partly by removing one weekend day from rest, and partly because it may accentuate the knowledge that one is putting in “extra” time. Working alone, when most others have left the organization, may have stronger effects than working an extra hour or two when the office is still relatively crowded with people. Constant overtime, in terms of an hour or two every day, may become a routine, and be accepted in time as part of the normal work week, whereas a few hours of overtime on odd days may be experienced as more unusual, and have a stronger effect.

The moderating effects of stress and anxiety on the relationship between overtime and health problems is still “up for grabs.” Looking at different types of overtime may help in finding exactly what aspect of overtime may cause these problems.


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This article copyright © 1996, David Zatz. Please do not reprint without written permission.

David Zatz is a writer, organizational development consultant, editor, photographer, and automotive/organizational historian.

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