Table 4.

Tests not ordered or ordered unnecessarily that might have affected perioperative management, according to assessment by house officer (n=926) or nurse (n=948)

	Tests not ordered					Tests ordered unnecessarily
	Assessed by house officers	Assessed by nurses	Total (n=1874)	Relative risk (95% CI)		Assessed by house officers	Assessed by nurses	Total (n=1874)	Relative risk (95% CI)
Electrocardiogram	47	35	82	0.73 (0.47 to 1.12)		18	16	34	0.87 (0.45 to 1.69)
Echocardiogram	26	23	49	0.86 (0.50 to 1.50)		32	18	40	0.55 (0.31 to 0.97)
Chest x ray examination	35	36	71	1.00 (0.64 to 1.59)		46	31	77	0.66 (0.42 to 1.03)
Urea and electrolytes	22	19	41	0.84 (0.46 to 1.55)		81	32	113	0.39 (0.26 to 0.58)
Liver function tests	15	24	39	1.56 (0.83 to 2.96)		45	24	69	0.52 (0.32 to 0.85)
Clotting function	11	2	13	0.18 (0.04 to 0.80)		34	5	39	0.14 (0.06 to 0.37)
Crossmatch/group and save	8	5	13	0.61 (0.20 to 1.86)		13	5	18	0.38 (0.13 to 1.05)
Pulmonary function tests	8	11	19	1.34 (0.54 to 3.32)		4	5	9	1.22 (0.33 to 4.53)
Haematology (for example, full blood count)	6	10	16	1.63 (0.59 to 4.46)		39	6	45	0.15 (0.06 to 0.35)
Cervical spine/thoracic inlet x ray examination	2	2	4	0.98 (0.14 to 6.92)		4	1	5	0.24 (0.03 to 2.18)
Other	21	24	45	1.12 (0.63 to 1.99)		35	21	56	0.59 (0.34 to 1.00)