The purpose of this research is to develop a multidimensional psychometric test instrument to assess cognitive functioning in the elderly which will have equivalent English and Spanish versions. Statistical methods associated with Item Response Theory (IRT) will be used for test development, and an important goal of this project will be to test the efficacy of these methods for multilingual neuropsychological test development. Homogeneous scales which assess broad ability ranges applicable to both patients with moderately severe dementia and high functioning normals will be developed. The scales will measure 12 abilities that have been shown to be important in neuropsychological and cognitive research with the elderly. Scales will be matched according to important psychometric characteristics to facilitate assessment of differential patterns of cognitive deficit independent of psychometric artifact. IRT procedures will be used in test construction to minimize cultural and language bias of items and to construct provisional norms for the final scales. Test development will be based upon a sample of 400 normal elderly (200 English speaking and 200 Spanish speaking). In addition, a group of dementia patients and a group of high functioning, non-elderly normals will be used to assure that items are included which will provide low and high end discrimination for all of the abilities assessed. This will be a three year project. Item development and pilot testing will occur during months 1 to 6. Recruitment and testing of the normal elderly derivation. sample will occur during months 7 to 30. Statistical analysis, item selection, calculation of provisional norms, and evaluation of efficacy of test development procedures will be completed during months 31 to 36.