Validation of cognitive screening questionnaire for neurological disorders (CSQND) for screening of cognitive complaints among patients with multiple sclerosis

Background The prevalence of cognitive impairment (CI) can reach up to 65% among multiple sclerosis (MS) patients. Self-administered screening questionnaires can offer a valuable solution for screening MS patients for cognitive complaints. The cognitive screening questionnaire for neurological disorders (CSQND) is an Arabic self-administered questionnaire that has been developed to screen patients with various neurological disorders attending neurology clinics. The aim of this study was to assess cognitive complaints and to validate the CSQND as a screening tool among Egyptian MS patients. Results Four-hundred MS patients and 400 controls were included in this study. All 400 patients and 400 controls were subjected to the CSQND, only 50 out of the 400 patients and 50 out of the 400 controls retook the CSQND 1 week later to establish test-retest reliability. Fifty patients and 50 controls were assessed by the symbol digit modalities test (SDMT) to establish concurrent validity. Thirty-four percent of patients complained of memory problems, 51% complained of concentration difficulties, 34% complained of language difficulties and 22.5% complained of space and time disorientation. Multiple sclerosis patients had significantly more cognitive complaints (12.4 +/- 12.6) compared to controls (6.2 +/- 6.8) when screened using the CSQND (P < 0.000001). Total scores of CSQND were positively significantly correlated to age at onset, total disease duration, EDSS scores and total number of relapses, (r = 0.14; 0.275; 0.3; 0.167, respectively), P < 0.05 for all. Agreement was found between CSQND results and the SDMT results, where the line of equality lied within the 95% confidence interval of the mean. A significant positive correlation was found between the CSQND results at the first application and upon retesting both in patients (R = 0.9, P = 0.0001) and controls (R = 0.85, P = 0.0001). Conclusions The CSQND was found to be a simple, valid, and reliable self-administered questionnaire to screen for cognitive complaints in MS patients.