Activities of Daily LivingGeriatric AssessmentDisabled PersonsDisability EvaluationMobility LimitationIndependent LivingCognition DisordersLongitudinal StudiesNeuropsychological TestsFrail ElderlyMental Status ScheduleAgingResidence CharacteristicsCross-Sectional StudiesCognitionHealth StatusQuestionnairesUnited StatesAlzheimer DiseaseLogistic ModelsAge FactorsItalyHealth SurveysProspective StudiesLinear ModelsSeverity of Illness IndexReproducibility of ResultsQuality of LifeSocioeconomic FactorsCohort StudiesPredictive Value of TestsPrevalenceFollow-Up StudiesRisk FactorsTime Factors