Table 2.

Comparison of Predicted Behavior Regularity Index Versus Actual Shiftwork Schedule

	Actual shiftwork schedule
Computed behavior regularity	Dayshift	Nightshift
Regular	24	1
Irregular	1	10

Computed behavior regularity index was calculated using linear regression. We then compared the predicted shiftwork schedule (e.g. regular behavior index was hypothesized to indicate an actual dayshift schedule), whereas an irregular behavior index was hypothesized to indicate an actual nightshift schedule).