Table 3.

Comparison of R-squared values using three methods (method 1: linear interpolation; method 2: LSR curve fitting; and method 3: iterative refinement).

Herbal medicine	Method 1	Method 2	Method 3
1 (Dwarf Lilyturf Tuber)	0.7737	0.8861	0.9617
2 (Radix Glehniae)	0.6281	0.8254	0.9382
3 (Barbary Wolfberry)	0.8886	0.8151	0.9172
4 (Chinese Angelica)	0.5452	0.8493	0.9464
5 (Dried Rehmannia Root)	0.8382	0.8481	0.9490
6 (Szechwan Chinaberry)	0.8316	0.9065	0.9417