Enzymatic colorimetric assay of inorganic phosphate.

Vol.33, No.2, 1987 in June 1986, after recahibration of the glucose method, gave results equal to the survey mean: 640 and 1110 mg/L, respectively. The addition of two more calibration points solved our problem. However, we do not want to imply that five or more calibration points are required. The important question is not how many calibration points are used, but rather, are the concentrations for the analyte at the calibration points inclusive of the entire useful range of the method? Thus, for accurate results for CSF glucose by the aca, it is important to include calibration points similar to that of the glucose concentration in CSF, to minimize proportional and systematic biases.