Table 2.

Count of events during the total observational time

	MIS (n = 27)			CS (n = 26)			Total	MIS vs CS
	Count	Max count	Mean	Count	Max count	Mean		P value
Environmental
Total	1,145	114	0.48a	1,594	208	0.54a	2739	NS
Door movements	925	90	0.39a	1,275	174	0.43a	1812	NS
Telephone	112	11	0.05a	165	28	0.05a	268	NS
Beeper	41	8	1.52	77	13	2.96	118	NS
Radio	9	2	0.33	20	2	0.77	29	<0.01
Case-irrelevant conversation	58	11	2.15	57	9	2.19	115	NS
Technical
Total	69	8	2.56	18	3	0.69	87	<0.01
Equipment	45	6	1.67	11	2	0.42	56	<0.01
Instruments	24	2	0.89	7	3	0.12	31	<0.01
Social
Total	43	9	1.59	27	8	1.04	70	NS
Communication	34	7	1.26	22	7	0.85	56	NS
Teamwork	9	2	0.33	5	1	0.19	14	NS
Organizational
Total	13	3	0.48	0	0	0.00	13	<0.01

MIS minimally invasive surgery; CS conventional surgery; Count total count of all procedures; Max count highest count reached during one procedure; Mean per procedure (count divided by number of procedures) if no correlation was found between count and procedure time; NS not significant

^aPer minute if a correlation was found between count and procedure time (count divided by procedure time)