Diagnostic performance of short portable mental status questionnaire for screening dementia among patients attending cognitive assessment clinics in Singapore.
BACKGROUND
The Short Portable Mental Status Questionnaire (SPMSQ) is a brief cognitive screening instrument, which is easy to use by a healthcare worker with little training. However, the validity of this instrument has not been established in Singapore. Thus, the primary aim of this study was to determine the diagnostic performance of SPMSQ for screening dementia among patients attending outpatient cognitive assessment clinics and to assess whether the appropriate cut-off score varies by patient's age and education. A secondary aim of the study was to map the SPMSQ scores with Mini-Mental State Examination (MMSE) scores.


METHODS
SPMSQ and MMSE were administered by a trained interviewer to 127 patients visiting outpatient cognitive assessment clinics at the Singapore General Hospital, Changi General Hospital and Tan Tock Seng Hospital. The geriatricians at these clinics then diagnosed these patients with dementia or no dementia (reference standard). Sensitivity and specificity of SPMSQ with different cut-off points (number of errors) were calculated and compared to the reference standard using the Receiver Operator Characteristic (ROC) analysis. Correlation coefficient was also calculated between MMSE and SPMSQ scores.


RESULTS
Based on the ROC analysis and a balance of sensitivity and specificity, the appropriate cut-off for SPMSQ was found to be 5 or more errors (sensitivity 78%, specificity 75%). The cut-off varied by education, but not by patient's age. There was a high correlation between SPMSQ and MMSE scores (r = 0.814, P <0.0001).


CONCLUSIONS
Despite the advantage of being a brief screening instrument for dementia, the use of SPMSQ is limited by its low sensitivity and specificity, especially among patients with less than 6 years of education.
Program in Health Services and Systems Research, Duke-NUS Graduate Medical School, Singapore.
Chetna
C
Malhotra
Angelique
A
Chan
David
D
Matchar
Dennis
D
Seow
Adeline
A
Chuo
Young Kyung
YK
Do
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000554:Ambulatory Care Facilities / Q000706:statistics & numerical data; D057186:Comparative Effectiveness Research; D003704:Dementia / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D004522:Educational Status; D005260:Female; D015577:Geriatric Assessment / Q000379:methods / Q000706:statistics & numerical data; D006801:Humans; D007361:Intelligence Tests / Q000592:standards / Q000706:statistics & numerical data; D008297:Male; D008403:Mass Screening / Q000379:methods / Q000592:standards; D016743:Mental Competency; D008875:Middle Aged; D012372:ROC Curve; D012015:Reference Standards; D015203:Reproducibility of Results; D012846:Singapore / Q000453:epidemiology