Table 1.
Linear and Second Order Fit to n = 6 Sensors at Glucose Concentrations of Approximately 20, 50, 100, 200, 400, 600, 750, 850 mg/dL.
| Line fits and R2 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| P71-S1 | P71-S2 | P71-S3 | P71-S4 | P74-S1 | P74-S2 | P74-S3 | P74-S4 | Average | |
| x coef | 202.5595 | 206.1809 | 314.2437 | 218.3638 | 182.8645 | 205.3441 | 222.3670 | 222.3943 | 221.7897 |
| Intercept | −36.9354 | −38.2946 | −94.9531 | −35.9948 | −49.1950 | −60.6936 | −163.1160 | −42.1438 | −65.1658 |
| R2 | .9992 | .9989 | .9941 | .9990 | .9990 | .9991 | .9974 | .9979 | .9981 |
| Second order poly fits and R2 | |||||||||
| P71-S1 | P71-S2 | P71-S3 | P71-S4 | P74-S1 | P74-S2 | P74-S3 | P74-S4 | ||
| x^2 coef | 5.7834 | 6.8957 | 36.4643 | 7.3630 | 4.4833 | 5.5423 | 12.1146 | 10.9721 | 11.2024 |
| x coef | 176.4784 | 175.6263 | 197.9964 | 187.6789 | 159.7632 | 179.2818 | 159.3513 | 177.1182 | 176.6618 |
| Intercept | −21.3024 | −20.2732 | −37.8288 | −19.0989 | −32.8541 | −43.2117 | −105.5037 | −17.5080 | −37.1976 |
| R2 | 1.0000 | .9999 | .9997 | 1.0000 | .9998 | .9998 | .9998 | .9999 | .9999 |
Resulting R2 of .998 for linear fit and .999 for second order fit demonstrate a very linear relationship between glucose levels and sensor output and support the simple application of 2-point linear calibration values.