Development of the Central Africa Daily Functioning Interference Scale for Dementia Diagnosis in Older Adults: The EPIDEMCA Study.

BACKGROUND: There are a few validated tools capable of assessing the dimensions essential for the diagnosis of dementia and cognitive disorders in sub-Saharan Africa.

OBJECTIVES: Our aim was to develop an adapted tool, the Central African - Daily Functioning Interference (DFI) scale.

METHODS: An initial 16-item scale of activity limitations and participation restrictions was completed by 301 participants with low cognitive performances to assess their level of DFI. A psychometric evaluation was performed using Item Response Theory.

RESULTS: A unidimensional 10-item scale emerged with a reasonable coverage of DFI (thresholds range: -1.067 to 1.587) with good item discrimination properties (1.397-4.076) and a high reliability (Cronbach's al pha = 0.92). The cutoff for detecting 96% of those with dementia was with a latent score ≥0.035 that corresponds to the LAUNDRY limitation.

CONCLUSIONS: These results provide valuable support for the reliability and internal validity of an operational 10-item scale for DFI assessment used in Central Africa for the diagnosis of dementia in the elderly.