Table 2

Preliminary sample size calculation for the large FLUID trial for a range of plausible sample size parameters

0.9% Saline proportion	Ringer’s lactate proportion	Within-period ICC	Average cluster size per month	Cluster autocorrelation coefficient	Correlation between cluster means	Required # clusters after rounding
0.16	0.15	0.001	1000	0.75	0.38	16
0.16	0.15	0.001	1000	0.95	0.48	16
0.16	0.15	0.001	1000	1	0.50	14
0.16	0.15	0.005	1000	0.75	0.63	24
0.16	0.15	0.005	1000	0.95	0.79	16
0.16	0.15	0.005	1000	1	0.83	14
0.16	0.15	0.01	1000	0.75	0.68	28
0.16	0.15	0.01	1000	0.95	0.86	18
0.16	0.15	0.01	1000	1	0.91	14
0.16	0.15	0.001	1500	0.75	0.45	8
0.16	0.15	0.001	1500	0.95	0.57	6
0.16	0.15	0.001	1500	1	0.60	6
0.16	0.15	0.005	1500	0.75	0.66	14
0.16	0.15	0.005	1500	0.95	0.84	8
0.16	0.15	0.005	1500	1	0.88	6
0.16	0.15	0.01	1500	0.75	0.70	20
0.16	0.15	0.01	1500	0.95	0.89	8
0.16	0.15	0.01	1500	1	0.94	6