Background: Our aims were to develop a Spanish version of the short portable mental status questionnaire (SPMSQ) (Pfeiffer's test) and to validate the resultant Spanish version of the test among a general population aged 65 years or older.
Patients, material and methods: First, we developed the Spanish version of the SPMSQ by means of a cross-cultural adaptation methodology. Patients were the assessed by independent teams in two sessions the same day. The first team (two trained psychiatrists and one trained family physician) carried out a standardised neuropsychological assessment to diagnose cognitive impairment/dementia according to ICD-10 criteria which was regarded as the reference "gold standard" to calculate validity parameters (sensitivity and specificity). The second team (family physicians/nurses) assessed the presence of cognitive impairment with the Spanish version of the SPMSQ.
Results: 255 subjects (66.7%, females) underwent the assessment. Mean age was 74.5 years and 65.5% of them were illiterate. The inter-rater reliability and test-retest reliability of the SPMSQ Spanish version were 0.738 (p < 0.001), and 0.925 (p < 0.001), respectively,with a convergent validity of 0.74 (p < 0.001) and a discriminant validity of 0.230 (p < 0.001). The internal consistency was high with an *value of 0.82. The area under the ROC curve was 0.89. Sensitivity and specificity were 85.7 and 79.3, respectively (cut-off of 3 or more).
Conclusions: The Spanish version of the SPMSQ test has a good reliability and validity. For clinical use, a cut-off of 3 appears to be most useful. When illiterate patients are assessed, the it is recommended to employ a cut-off of 4 or more.