Regression lines for a 25-μg fluconazole disk and different Candida species, calculated using the mean SRA equation constants A and B obtained from tests of clinical isolates. The SRA equation uses the zone size squared, which gives a curved appearance of the regression lines in this linear plot. Abbreviations: C.albic., C. albicans; C.glabr., C. glabrata; C.lusit., C. lusitaniae; C.paraps., C. parapsilosis; C.tropic., C. tropicalis.