Background: In many English-speaking countries neuropsychological assessment of non-English speakers is often performed in English or through an interpreter. Relying on interpreters often involves unstandardized and ad hoc translations of tests which may limit valid assessment.
Methods: In a sample of 75 Italian-born elderly Australians from the general community (48 women and 27 men, aged 56-90 years) we administered standardized and normed psychological tests in both English (WMS-III, WAIS-III, BNT, Schonell Graded Word Reading Test) and Italian (Milan Overall Dementia Assessment, MODA). We examined the hypothesis that long-term retrieval ability assessed in English is primarily influenced by cognitive abilities assessed in Italian and by English language competence.
Results: Regression analysis showed that the strongest predictor of long-term retrieval in English was long-term retrieval in Italian (R2 = 0.229, F(72) = 29.12, p<0.01). After inclusion of an estimate of general cognitive ability in Italian, English language competence failed to add significantly to variance explained in memory tested in English (p > 0.05).
Conclusions: Results of the present study support the view that long-term retrieval memory is not significantly affected by second language proficiency after control of cognitive ability assessed in Italian. As a consequence, if an Italian-born elder Australian with English as a second language scores poorly on a diagnostic memory test, this result may be due to cognitive impairment rather than language issues. If, instead, we attribute poor performance to language competence, an increased risk of false negative diagnosis may arise.