Table 1.

Change in task duration (%) detectable with 80% power, assuming 320 h of observations divided equally between intervention and control wards in a controlled before-and-after design

CV of task duration	Number of tasks per hour (for given activity)
	5	10	15	20	25	30
0.5	13.3	9.4	7.7	6.6	5.9	5.4
1.0	26.6	18.8	15.3	13.3	11.9	10.9
1.5	39.9	28.1	23.0	19.9	17.8	16.3
2.0	53.2	37.5	30.7	26.6	23.8	21.7

CV, coefficient of variation.