INTERRATER RELIABILITY OF CRITICAL FLICKER FUSION IN PATIENTS WITH PRIMARY DEGENERATIVE DEMENTIA OF THE ALZHEIMER-TYPE (PDDAT)

Fifteen female and six male patients with primary degenerative dementi a of the Alzheimer type (PDDAT) were included in the study. Patients h ad a mean age of 78.8 +/- 6.25 years (range 67-89). Diagnosis of PDDAT was based on DSM-III-R criteria. Pearson product moment correlation c oefficients (r) were calculated to determine the interrater reliabilit y of critical flicker fusion and its subcomponents, flicker and fusion thresholds. The inter-rater reliability of these three measures were 0.943 (p < 0.01), 0.84 (p < 0.01) and 0.903 (p < 0.01), respectively. The measurement of critical flicker fusion threshold and its subcompon ents is a quick, easy and reliable technique in patients with PDDAT. F uture work will need to examine the pharmacosensitivity of this measur e in patients with Alzheimer's disease. This technique may have a usef ul role in the evaluation of new drugs for the treatment of Alzheimer' s disease in a clinical trial context.