Table 5.

Overall risk of prescription errors by shift and designation of doctors.

	Odds ratio	95% CI
Crude	0.66	0.53	0.83
Shift worked
Morning	1.08	0.64	1.82
Afternoon	0.67	0.48	0.95
Evening	0.54	0.37	0.80
M-H combined	0.69	0.55	0.87
Designation
Instructor	0.97	0.69	1.37
Resident	0.39	0.24	0.65
SHO	0.52	0.35	0.78
M-H combined	0.65	0.52	0.82

CI, confidence interval; M-H, Mantel-Haenszel; SHO, senior house officer.