The efficacy of Hormone Replacement Therapy (HRT) for cognitive health in postmenopausal women has been systematically questioned during the last decade. Although epidemiological and clinical research have suggested that HRT may exert protective effects on the prophylaxis of neurodegenerative diseases and beneficial effects on cognitive function, the Women's Health Initiative Memory Study (WHIMS) contradicted these claims. The purpose of this study was to reassess the effects of HRT on cognitive function in an attempt to account for two potential confounding factors that might have generated the negative clinical findings reported by the WHIMS i.e. subjects' age and educational level.