Method I Method II
Concentration (ng mL-1) Repeatability (intra-day precision)* Intermediate Precision (inter- day precision)* Repeatability (intra-day precision)* Intermediate Precision (inter- day precision)*
 %RSD  SE %RSD  SE  %RSD  SE %RSD  SE
 0.5  1.509 0.0004 5.605 0.0015  1.358 0.0004 3.624 0.0012
 1.0     6.766 0.0035     3.239 0.0016
 2.0 0.896 0.0011 5.814 0.0073 1.707 0.0024 2.251 0.0027
 3.0     2.127 0.0040     3.784 0.0067
 4.0     6.265 0.0162     2.657 0.0066
 5.0     5.467 0.0162     3.589 0.0105
*Indicates mean of three replicates, RSD= Relative standard deviation, SE= Standard error
Table 3: Precision analysis of method I and II.