Primidone analyses: correlation of gas-chromatographic assay with enzyme immunoassay

Serum specimens from patients on primidone therapy were assayed by two currently available procedures: a commercially available enzyme immunoassay (EMIT) and a published gas-chromatographic procedure. Both procedures were done with commercially available materials and equipment. Results by the two procedures agreed well, which suggests that the two methods could be used interchangeably. For the 94 specimens studied, the correlation coefficient was 0.98, and the least-squares values of slope and intercept were, respectively, 0.97 and 0.51 mg/liter.