Background: Dementia screening in elderly people with low education can be difficult to implement. For these subjects, informant reports using the long (L) (26 items) and short (C) (16 items) versions of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) can be useful. The objective of the present study was to investigate the performance of Brazilian versions of the IQCODE L, S and a new short version (SBr) (15 items) in comparison with the Mini-mental State Examination (MMSE) for dementia screening in elderly people with low education.

Methods: Thirty-four patients with mild to moderate dementia, diagnosed according to ICD-10 criteria, and 57 controls were evaluated and divided into three groups based on their socioeconomic status and level of education. Patients were evaluated using the MMSE and the informants were interviewed using the IQCODE by interviewers blind to the clinical diagnosis.

Results: Education was correlated with MMSE results (r = 0.280, p = 0.031), but not with the versions of the IQCODE. The performance of the instruments, evaluated by the ROC curves, was very similar, with good internal consistency (Cronbach's α = 0.97). MMSE correctly classified 85.7% of the subjects while the three IQCODE versions (L, S and SBr) correctly classified 91.2% of the subjects.

Conclusions: The long, short and the new short Brazilian IQCODE versions can be useful as a screening tool for mild and moderate patients with dementia in Brazil. The IQCODE is not biased by schooling, and it seems to be an adequate instrument for samples with low levels of education.

Background: Differential item functioning (DIF) exists when test item responses by members of different demographic groups are statistically different when controlling for ability. DIF may indicate item bias. Our objective was to determine whether items from the Italian Mini-mental State Examination (MMSE) had DIF related to educational attainment, age, gender and occupation. We were also interested in exploring the significance of DIF in screening tests.

Methods: In a two-stage study from Granarolo, Italy, residents over age 61 (n = 495) were evaluated with the Italian MMSE. Those with MMSE scores of 28 or lower were further evaluated for dementia. MMSE results were coded in 10 item bundles. We used ordinal logistic regression to determine whether item bundles had DIF.

Results: Six of the 10 MMSE item bundles had DIF in educational attainment subgroups. Four of these six bundles also had DIF related to age. Items that required literacy were much harder for those with lower educational attainment.

Conclusions: DIF related to education appeared at as few as 3 years of formal schooling. These findings suggest cautious interpretation of data from studies using the Italian MMSE in populations with heterogeneous educational backgrounds. DIF is especially troublesome for two-stage studies that use screening tests.

Introduction: Brief cognitive tests such as the Mini-mental State Examination (MMSE) and the Informant Questionnaire for Cognitive Decline in the Elderly (IQCODE) have been used to detect cognitive impairment and dementia in studies of stroke patients. However, there are few data on their validity for such use. We have evaluated their validity in detecting cognitive impairment not dementia (CIND) and dementia in a community-based sample of first-ever stroke patients.

Methods: The standardized MMSE (S-MMSE) and the 16-item IQCODE were administered to 79 patients 1 year after a first-ever stroke. CIND and dementia were diagnosed independently using a comprehensive cognitive battery. The performances of the two tests were evaluated using receiver operating characteristic (ROC) analyses. Combined performance was evaluated when their scores were used in parallel (the “or rule”), in series (the “and rule”) or as a weighted sum (the “weighted sum rule”).

Results: Both tests were extremely poor at detecting CIND individually and in combination. For dementia, at traditional cut-points, the S-MMSE (≤23) was insensitive (0.50, 95% CI 0.16–0.84) and the IQCODE (≥3.30) nonspecific (0.63, 95% CI 0.51–0.75). An acceptable balance between sensitivity and specificity was achieved for dementia using the “or rule” combination, but with only modest positive predictive value.

Conclusions: The S-MMSE and the IQCODE were individually poor at detecting CIND and dementia after a nonaphasic first-ever stroke. The combination was useful in detecting dementia but it does not replace the need for detailed neuropsychological tests.

Health policy documents recommend screening for cognitive impairment, although in practice this is not implemented. This article looks at the issues which require consideration in implementing a screening programme. These include factors pertinent to the disease under consideration, resources, both personnel and time, lack of experience of cognitive screening at a primary care level, use of screening instruments and uncertainty about management of positive cases. Only by identifying the practical difficulties involved in screening, can steps can be taken to overcome them and to implement screening programmes which are acceptable to the population under consideration and their primary care physicians.