Relationships amongst four important pharmacological parameters for quinoline methanols were evaluated for evidence of correlations. A possible linear correlation between maximum and free brain concentration is evident on visual inspection of the data, and was confirmed mathematically (r2 = 0.89, P < 0.0001). There was no relationship evident between the other variables. Data are presented in a log format for ease of visualization. The correlation coefficient was calculated based on raw (not log transformed) data.