Abstracts

RATIONALE: The ability to estimate the magnitude of self-perceived changes in cognitive function following epilepsy surgery is an important topic for quality of life researchers. However, limited attention has been given to determining what constitutes reliable and meaningful self-reported cognitive change. Establishment of such standardized change could be useful in determining the magnitiude and direction of self-appraised cognitive change following epilepsy surgery. The objective of the present study was to calculate RCI and SRB change score norms for a newly developed self-report questionnaire of cognitive functioning (MASQ).
METHODS: The MASQ was administered to 35 patients with complex partial seizures (primarily temporal lobe epilepsy) on two occasions (mean test-retest interval was 6 months). Patients did not have major psychopathology and were on stable antiepileptic medications. RCI and SRB change scores were calculated. These methods help to correct for test-retest methodological artifacts including practice effect and regression to the mean. Adjustments for baseline ratings, patient age, education, gender, age of seizure onset, and seizure duration were made with the SRB method. 90% confidence interval cuttoff scores and SRB equations were calculated for the five MASQ cognitive domains (Language, Visual-Perception, Verbal Memory, Visual-Spatial Memory, and Attention/Concentration).
RESULTS: Test-retest reliabilities for the MASQ domains were as follows: Language (r =.84), Visual-Perception (r =.71), Verbal Memory (r =.75), Visual-Spatial Memory (r =.54), Attention/Concentration (r =.65). Utilizing a modified practice adjusted RCI formula 90% confidence intervals ranged from a low of [plusminus]1.5 (Visual-Perception) to a high of [plusminus]4.2 (Visual-Spatial Memory). Baseline self-report rating was the single largest contributor to each of the regression equations predicting retest self-ratings. Gender was the only other predictor variable to enter the regression equations .
CONCLUSIONS: The present study calculated Reliable Change Indices and Standardized Regression-Based change scores for a newly developed measure of self-reported cognitive functioning (MASQ) in patients with partial complex seizures. The present findings indicate that self-appraisal of subjective cognitive functioning is variable across cognitive domains and that both baseline rating and gender influence self-rating at retest. Employing empirically-based statistical methods provides reliable and valuable information when attempting to determine patient perception of cognitive changes following epilepsy surgery.
Support: Epilepsy Foundation of America Young Investigator Award to Roy C. Martin