While the cataractogenic effects of corticosteroids are beyond dispute, disagreement exists concerning effects of total dose, intensity of dose, and duration of administration on cataract formation. We studied 106 adult male patients matched for age, race, and socioeconomic status. We compared posterior subcapsular (PSC) cataract formation among those with (39) and without (67) a history of systemic corticosteroid therapy. Difference in incidence of PSC opacities among patients with and without a history of corticosteroid therapy was statistically significant. However, no statistically significant correlation was found between PSC opacities and total steroid dose, weekly dose (intensity), duration of dose, or age of patient. Our findings agree with some recent literature that suggests the most important factor in steroid-induced PSC cataract formation may be variability in individual susceptibility to side effects of corticosteroids. We suggest abandoning the concept of a "safe" dose.