Table 2.

Inter- and intra-day precision in plasma and cerebrospinal fluid samples

Plasma concentration				CSF concentration
Added (ng/ml) donepezil	C. V.  %	Mean ± SEM	N	Added (ng/ml) donepezil	C. V.  %	Mean ± SEM	N
Inter-day				Inter-day
6.25	3.23	6.2 ± 0.2	10	6.25	4.76	6.3 ± 0.3	10
12.5	3.25	12.3 ± 0.4	10	12.5	4.84	12.4 ± 0.6	10
25	3.13	25.6 ± 0.8	10	25	3.54	25.4 ± 0.9	10
50	2.23	49.4 ± 1.1	10	50	3.82	49.7 ± 1.9	10
100	1.73	98.3 ± 1.7	10	100	3.29	100.3 ± 3.3	10
Intra-day				Intra-day
6.25	4.76	6.3 ± 0.3	3	6.25	6.45	6.2 ± 0.4	3
12.5	4.84	12.4 ± 0.6	3	12.5	1.60	12.5 ± 0.2	3
25	4.59	26.1 ± 1.2	3	25	3.50	25.7 ± 0.9	3
50	2.18	50.5 ± 1.1	3	50	2.42	49.5 ± 1.2	3
100	2.02	99.1 ± 2.0	3	100	2.57	101.1 ± 2.6	3