The NEO-FFI is a reliable measure of premorbid personality in patients with probable Alzheimer's disease.
OBJECTIVE
To assess the inter-informant reliability, intra-informant reliability and internal consistency of the NEO-FFI as a measure of premorbid personality in patients with Alzheimer's Disease (AD).


METHODS
One hundred and five persons with NINCDS-ADRDA probable AD for the assessment of inter-informant reliability and internal consistency, and 30 for the assessment of intra-informant reliability.


METHODS
Premorbid personality was rated retrospectively by close relatives remembering the patient as he/she had been when aged in his/her forties. One hundred and five AD patients were rated by two separate informants. Thirty AD patients were rated by the same informant on separate occasions one year apart.


RESULTS
Inter-informant reliability for the five domain scores of the NEO-FFI was shown to range from fair to good when measured using the single measure Intraclass Correlation Co-efficient (ICC) (0.52-0.64), and to range from good to excellent when measured using the average ICC (0.68-0.78). Intra-informant reliability for four out of the five domains was shown to be excellent when measured using the single ICC (0.81-0.92), and good for the remaining domain (0.72). Intra-informant reliability was found to be excellent for all five domains when measured using the average ICC (0.84-0.96). Internal consistency of the five domains was good.


CONCLUSIONS
The NEO-FFI can be used reliably to measure premorbid personality in patients with probable AD. It may be useful to maximise reliability by using a mean domain score based on questionnaires completed by two or more informants who knew the patient well earlier in life.
Archer
Nicola
N
Section of Old Age Psychiatry, King's College London, Institute of Psychiatry, Section of Old Age Psychiatry, Denmark Hill, London, UK. n.archer@iop.kcl.ac.uk
Brown
Richard G
RG
Boothby
Harry
H
Foy
Catherine
C
Nicholas
Helen
H
Lovestone
Simon
S