Examining Executive Dysfunction with the Institute of Cognitive Neurology (INECO) Frontal Screening (IFS): normative values from a healthy sample and clinical utility in Alzheimer's disease.

BACKGROUND The Institute of Cognitive Neurology (INECO) Frontal Screening (IFS) is a brief neuropsychological tool recently devised for the evaluation of executive dysfunction in neurodegenerative conditions. OBJECTIVE In this study we present a cross-cultural validation of the IFS for the Portuguese population, provide normative values from a healthy sample, determine how age and education affect performance, and inspect its clinical utility in the context of Alzheimer's disease (AD). A comparison with the Frontal Assessment Battery (FAB) was undertaken, and correlations with other well-established executive functions measures were examined. METHODS The normative sample included 204 participants varying widely in age (20-85 years) and education (3-21 years). The clinical sample (n = 21) was compared with a sample of age- and education-matched controls (n = 21). Healthy participants completed the IFS and the Mini-Mental State Examination (MMSE). In addition to these, the patients (and matched controls) completed the FAB and a battery of other executive tests. RESULTS IFS scores were positively affected by education and MMSE, and negatively affected by age. Patients underperformed controls on the IFS, and correlations were found with the Clock Drawing Test, Stroop test, and the Zoo Map and Rule Shift Card tests of the Behavioral Assessment of the Dysexecutive Syndrome. A cut-off of 17 optimally differentiated patients from controls. While 88% of the IFS sub-tests discriminated patients from controls, only 67% of the FAB sub-tests did so. CONCLUSION Age and education should be taken into account when interpreting performance on the IFS. The IFS is useful to detect executive dysfunction in AD, showing good discriminant and concurrent validities.