Relationships of Cognitive Performance and Daily Function of Clients following Right Hemisphere Stroke: Predictive and Ecological Validity of the LOTCA Battery

The purpose of this study was to determine the relationship of cognitive performance, as measured by the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) battery, to daily function in patients following right hemisphere stroke. Furthermore, to explore the predictive power of cognitive performance using the LOTCA at the first rehabilitative stage after stroke to long-term functional outcomes. The method was a longitudinal research design at 3 points in time: admission to rehabilitation; discharge from the rehabilitation hospital; and at follow-up, six months after discharge, which in some cases reached one year post onset. Subjects were 40 consecutive patient admissions to a rehabilitation hospital. All patients were right-handed adults with a CT-proven, first, single, right hemispheric stroke. Based on their total cutoff score in the Behavioral Inattention Test (BIT) for unilateral spatial neglect, patients were divided into 2 subgroups: 19 with neglect and 21 without neglect. Instruments included the LOTCA, the Functional Independence Measure (FIM), the Rabideau Kitchen Evaluation and Phone use. Results showed that right hemispheric stroke patients with unilateral spatial neglect performed at a lower level than patients without neglect on all measures of cognitive skills, as well as daily functional tasks as measured by the FIM and kitchen tasks. Differences were significant in all testing periods. Relationships between cognitive and functional measures showed that visuomotor organization and thinking operations correlated at moderate to high levels in both subgroups. The predictive results from admission to follow-up suggest that unilateral spatial neglect is the major predictor of activities of daily living (ADL) and instrumental activities of daily living (IADL) task performance, however cognitive skills, especially the more complex integrated visuomotor and thinking skills, were significantly related to functional outcomes in the non-neglect group. Thus, they are crucial in the assessment of stroke patients. The predictive and ecological validity of the LOTCA battery was supported.

Normative data for the Tygerberg Cognitive Battery and Mini-Mental Status Examination in a South African population

BACKGROUND

Normative data for the Tygerberg Cognitive Battery (TCB) and Mini-Mental Status Examination (MMSE) (in South Africa) have not been formally examined before. The TCB was developed for the bedside pen-and-paper screening of cognitive impairment in each of the 6 main cognitive domains, including attention and concentration, speech, memory, praxis, gnosis, and executive functioning. The test is also used to diagnose different neuropsychiatric conditions. The MMSE is an established screen of cognitive status, which is often used as a comparative standard for novel screening tests such as the TCB. The TCB was initially developed in English and Afrikaans, and a Xhosa version was also initiated with this study so that the 3 most common languages of the region could be accommodated.

AIMS

The first aim of the study was to estimate normative test performance on the TCB and MMSE among controls, and the second aim was to develop a Xhosa version of the TCB.

METHODS

Assessments of the TCB and MMSE were carried out in a population of healthy individuals (n = 157). In addition, healthy Xhosa-speaking participants (n = 14) were screened using a Xhosa version of the TCB.

RESULTS

Reliability scores for all forms of the TCB were satisfactory. Age and education correlated significantly with TCB scores (r = -0.26, P < .01; r = 0.64, P < .01, respectively), whereas only education significantly correlated with MMSE scores (r = 0.32, P < .05). Normative values were calculated accordingly, that is, controlled for the effects of age and education. The TCB scores also correlated significantly with MMSE scores (r = 0.49, P < .05), demonstrating the potential of the TCB to serve as an alternate cognitive assessment tool, along with the MMSE, to focus neuropsychiatric investigations. Scores on the Xhosa version differed significantly on speech, praxis, and gnosis between the Afrikaans and English participant scores.

CONCLUSION

These normative data can be used to increase precision and to provide an impartial evaluation when applying TCB to evaluate the cognitive ability of neuropsychiatrically impaired adult patients. However, age and education effects should be considered when computing the results of cognitive assessment.