Abstract
A study was performed to compare the predictability of a reported Bayesian graphical method, the drug nomogram used in the Bayesian Computer Method and the Driessen Nomogram with that of a computerized Bayesian analysis method in the interpretation of serum phenytoin concentrations. It was found that the results generated by the graphical method were similar to those of the computer with a mean prediction error of 3.9 mg/day in the dose to achieve a concentration at steady-state of 20 ml/l. Overall the results of the graphical method were less biased and had more precision with a significant improvement in relative precision (P < 0.01) than the initial estimate or Driessen methods.