Psychometric properties and factor structure of the Neuropsychiatric Inventory Nursing Home version in an elderly neuropsychiatric population

BACKGROUND: The Neuropsychiatric Inventory (NPI) is an interview-based instrument designed to elicit information from an informal caregiver to evaluate behavioral disturbances in persons with dementia. Minor modifications of this instrument have produced the Neuropsychiatric Inventory-Nursing Home version (NPI-NH), a version specifically designed for interviewing professional care facility staff. The purpose of this investigation is to further understand the psychometric properties of the NPI-NH by examining its reliability, validity, and factor structure in an elderly neuropsychiatric population. METHOD: Participants were 204 elderly inpatients from a large provincial neuropsychiatric hospital in British Columbia, Canada. Data were collected as part of a patient needs assessment project. RESULTS: The internal consistency reliability of the NPI-NH was alpha=0.67. An exploratory principal axis analysis with varimax rotation revealed five factors that accounted for 63.2% of the variance. These factors reflect aspects of psychiatric disturbance associated with: (a) Agitation; (b) Mood; (c) Psychosis; (d) Sleep/Motor Activity; and (e) Elevated Behavior. Convergent and discriminant validity of the five factors by correlating them with other behavioral measures was considered satisfactory. CONCLUSIONS: These results provide support for the clinical use of the NPI-NH as a screen for neuropsychiatric symptoms in an elderly neuropsychiatric population. However, additional research is encouraged to further evaluate the clinical utility of the NPI-NH in nursing home and inpatient geriatric settings.