Presentation and adaptation of Boston Naming Test to the Greek population
and its reliability and validity according to the MMSE scale

Naming difficulty is one of the first language deficiencies in the primary stages of probable dementia of Alzheimer type (DAT) and it can be used as one of the diagnostic criteria for the disorganization of semantic memory. Its features are difficulties of the probable DAT patients in recalling the correct lexical labels, frequent pauses or circumlocutions in their effort to find the correct words. In the present research, our main aim was to investigate if the Boston Naming Test (BNT), a confrontation naming scale, can differentiate cognitively healthy old age people from the probable DAT patients and from the patients with other types of dementias (OTD). Our sample consisted of 85 cognitively healthy old age people, 74 probable DAT patients and 21 patients with OTD.The group of patients with OTD consisted of patients with vascular dementia, Lewy Body disease and mixed type of dementia.

The patients were selected on the basis of their meeting the criteria of Mini Mental State examination (MMSE), NINCDS-ADRDA and DSM-IV. We also used the Hachinski scale, the Hamilton scale and the Clinical Dementia Rating Scale. Then we administered the BNT, the confrontation naming scale, which consists of 60 black and white drawings on the basis of word frequency. The kind of “no cue”, “semantic”, and “phonological cues” answers is a useful index for assessing the quality of the patients' naming ability. The score of the patients was the sum of the “no cue” and the “semantic cues” answers.

The participants were matched on age and education, and the dementia groups on MMSE, too. We used the multiple variant analysis (ANOVA) in order to investigate if the “no cues”, the “semantic cues“ and the “phonologicalcues” answers, the total time and the BNT score can differentiate among the three groups. There was a statistically significant difference between the variable of diagnosis and the BNT scores, the mental status (MMSE), the “no cue” answers, the “phonological cues” answers and total time. The BNT score can differentiate cognitively healthy old age people from probable DAT patients (95,6%), and the “phonological cue“ answers can only differentiate probable DAT patients (mean=3) from the OTD (mean=9,9). There were significant effects of education on the BNT score using phonological cue, as well as interaction between education and the diagnosis in the basis of phonological cue answers, and the total time. This indicates that education is a protective factor in naming difficulties and that people with more years of formal education depending on the type of diagnosis can use phonological cues more sucessfully and achieve better results in less time. There is also interaction between the variables of diagnosis and age with respect to the phonological cue. This indicates that the younger old age people can use the phonological cues more successfully than the older ones.

Using discriminant analysis, we found that the degree of correct reordering of the three groups was 85%. Specificaly, 98,5% for cognitively healthy old age people, 78,4% for probable DAT patients and 52,4% for OTD patients. Therefore the conclusion is that the BNT score cannot differentiate probable DAT patients from OTD patients. Only the use of phonological cues can differentiate between the two groups of patients, as the probable DAT patients have difficulties recalling the lexical labels of the items. We also found strong correlation between the mental status as measured by MMSE scale and the naming ability as measured by BNT (r=81). Finally, the BNT scale was adapted to the Greek old age population matched for age and education, as the BNT is an aphasic scale for all ages.

Key words: Adaptation, Reliability, Validity, Alzheimer Disease, Naming Difficulties, Boston Naming Test (BNT), Greek Language, Aging.