Wechsler IQ, Hong Kong List Learning Test, and the BNI Screen for Higher Cerebral Functions
Florence D. M. Lai, MPhil
George P. Prigatano, PhD*
Clinical Psychology Department, Kowloon Hospital, Hong Kong
*Division of Neurology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona
Eighty-five Cantonese-speaking brain dysfunctional patients were administered a Cantonese version of the BNI Screen (BNIS) for Higher Cerebral Functions. They were also administered the Wechsler Adult Intelligence Scale—Revised Form (WAIS-R) and the Hong Kong List Learning Test (HKLLT). The BNIS Total score correlated 0.69 with Full-Scale IQ, and the HKLLT correlated 0.51 with the delayed verbal recall total score from the BNIS. These findings suggest that this adapted version of the BNIS can be used to assess higher cerebral functions in Cantonese-speaking populations.
Key Words: BNI Screen, brain injury, higher cerebral functions, neuropsychological testing
Prigatano and Palencia attempted to extend the construct and concurrent validity of the BNI Screen (BNIS) for Higher Cerebral Functions by specifically correlating the Total score on the BNIS with the Halstead Impairment Index (HII) score and the IQ scores obtained from the Wechsler Adult Intelligence Scale-Revised (WAIS-R) Form. Correlations of .50 to .60 were obtained, supporting the proposition that the BNIS is a valid neuropsychological measure. The present study attempted to partially replicate these findings using a Cantonese-speaking population in Hong Kong.
The Speech and Language subtests were translated into Cantonese. The item used to stimulate spontaneous affect was also changed to account for cultural differences between the Hong Kong population and the American population in which this test was standardized. This type of translation is similar to that reported in a German translation of the BNIS (See Reliability and Validity Studies for the German Adaptation of the BNI Screen for Higher Cerebral Functions in this issue).
The relationship between the BNIS Total score and various subtest scores on a Cantonese translation of the WAIS-R was calculated. The Hong Kong List Learning Test (HKLLT) also was included to assess whether the delayed verbal memory score on the BNIS correlates with performance on this test. In this way, an attempt was made to expand the previous validation study conducted by Prigatano and Palencia.
Four hypotheses were studied. (1) The BNIS Total score would significantly correlate positively with the Full-Scale WAIS-R IQ. (2) The BNIS Speech and Language score would significantly correlate positively with the Verbal IQ. (3) The BNIS Visuospatial score would significantly correlate positively with the Performance IQ. (4) The verbal delayed recall score (i.e., recalling three words with distraction) on the BNIS would correlate positively with a 10-minute delayed recall on the HKLLT.
Materials and Methods
Eighty-five patients (61 males, 24 females; mean age, 43.5 years; range, 11 to 69 years; standard deviation (SD)=13.3) with documented brain disorders (Table 1) were transferred to our hospital from an acute hospital. Their mean numbers of years of education was 9.5 (range, 0 to 18 years; SD=3.9). The mean chronicity (time from onset of brain disorder to testing) was 17 months (range, 1 to 132 months, SD=17). The inclusion criteria for the study were as follows: (1) a medically documented brain disorder, (2) complete neuropsychological test protocols, (3) no history of psychiatric disturbance, and (4) able to read and write in Cantonese.
The WAIS-R and HKLLT were administered according to standardized procedures. The WAIS-R consists of 11 subtests, which are used to derive a Verbal IQ and Performance IQ. These two composite scores are combined to calculate the Full-Scale IQ. The HKLLT consists of two different lists of 16 Chinese words, all of which are two-character nouns. Thirty minutes are required to administer the verbal learning, 10-minute and 20-minute delayed recall tests, and recognition tests.
Like the original BNIS, the Cantonese version of the BNIS consists of a set of plastic cards, record form, and standard stopwatch. The test requires 10 to 25 minutes to administer. High scores suggest less impaired cognitive functioning than low scores. Subtest scores indicate patients' performance in each cognitive domain. A total score of less than 47 from the possible 50 points suggested the possible presence of cognitive deficits in an American population.
All neuropsychological tests were administered by the first author. All patients were given the BNIS (Cantonese version) first, followed by the HKLLT and WAIS-R, respectively.
All statistical analyses were performed with Statistical Package for the Social Sciences–10.1 for Windows. Descriptive statistics were calculated. Pearson correlation coefficients were calculated for the WAIS-R Full-Scale IQ and BNIS Total scores. The scores on the Speech and Language and Visuospatial subtests of the BNIS were correlated with WAIS-R Verbal IQ and Performance IQ. The BNIS score for the three verbal delayed items were correlated with the 10-minute delayed recall subtest of the HKLLT.
Correlations of BNIS Total Score with WAIS-R IQ Scores
The correlation between the BNIS Total score and the WAIS-R Full- Scale IQ was 0.69 (p<.01). In two independent groups of brain dysfunctional patients, Prigatano and Palencia reported correlations of .58 (p<0.1) and .53 (p<.01). Thus, the correlation obtained from the Hong Kong population is of the same magnitude and direction as reported in the American population, supporting the first hypothesis. It is important to note that the magnitude of the correlations has remained the same across these two different cultures using three different samples of brain dysfunctional patients.