TY - JOUR
T1 - Facilitating clinical use of the Amsterdam Instrumental Activities of Daily Living Questionnaire
T2 - Normative data and a diagnostic cutoff value
AU - Postema, Merel C
AU - Dubbelman, Mark A
AU - Claesen, Jürgen
AU - Ritchie, Craig
AU - Verrijp, Merike
AU - Visser, Leonie
AU - Visser, Pieter-Jelle
AU - Zwan, Marissa D
AU - van der Flier, Wiesje M
AU - Sikkes, Sietske A M
PY - 2024/3/8
Y1 - 2024/3/8
N2 - OBJECTIVE: The Amsterdam Instrumental Activities of Daily Living Questionnaire (A-IADL-Q) is well validated and commonly used to assess difficulties in everyday functioning regarding dementia. To facilitate interpretation and clinical implementation across different European countries, we aim to provide normative data and a diagnostic cutoff for dementia. METHODS: Cross-sectional data from Dutch Brain Research Registry ( = 1,064; mean ( ) age = 62 ± 11 year; 69.5% female), European Medial Information Framework-Alzheimer's Disease 90 + ( = 63; Mage = 92 ± 2 year; 52.4% female), and European Prevention of Alzheimer's Dementia Longitudinal Cohort Study ( = 247; Mage = 63 ± 7 year; 72.1% female) were used. The generalized additive models for location, scale, and shape framework were used to obtain normative values ( -scores). The beta distribution was applied, and combinations of age, sex, and educational attainment were modeled. The optimal cutoff for dementia was calculated using area under receiver operating curves (AUC-ROC) and Youden Index, using data from Amsterdam Dementia Cohort ( = 2,511, Mage = 64 ± 8 year, 44.4% female). RESULTS: The best normative model accounted for a cubic-like decrease of IADL performance with age that was more pronounced in low compared to medium/high educational attainment. The cutoff for dementia was 1.85 standard deviation below the population mean (AUC = 0.97; 95% CI [0.97-0.98]). CONCLUSION: We provide regression-based norms for A-IADL-Q and a diagnostic cutoff for dementia, which help improve clinical assessment of IADL performance across European countries.
AB - OBJECTIVE: The Amsterdam Instrumental Activities of Daily Living Questionnaire (A-IADL-Q) is well validated and commonly used to assess difficulties in everyday functioning regarding dementia. To facilitate interpretation and clinical implementation across different European countries, we aim to provide normative data and a diagnostic cutoff for dementia. METHODS: Cross-sectional data from Dutch Brain Research Registry ( = 1,064; mean ( ) age = 62 ± 11 year; 69.5% female), European Medial Information Framework-Alzheimer's Disease 90 + ( = 63; Mage = 92 ± 2 year; 52.4% female), and European Prevention of Alzheimer's Dementia Longitudinal Cohort Study ( = 247; Mage = 63 ± 7 year; 72.1% female) were used. The generalized additive models for location, scale, and shape framework were used to obtain normative values ( -scores). The beta distribution was applied, and combinations of age, sex, and educational attainment were modeled. The optimal cutoff for dementia was calculated using area under receiver operating curves (AUC-ROC) and Youden Index, using data from Amsterdam Dementia Cohort ( = 2,511, Mage = 64 ± 8 year, 44.4% female). RESULTS: The best normative model accounted for a cubic-like decrease of IADL performance with age that was more pronounced in low compared to medium/high educational attainment. The cutoff for dementia was 1.85 standard deviation below the population mean (AUC = 0.97; 95% CI [0.97-0.98]). CONCLUSION: We provide regression-based norms for A-IADL-Q and a diagnostic cutoff for dementia, which help improve clinical assessment of IADL performance across European countries.
KW - A-IADL-Q
KW - clinical implementation
KW - dementia
KW - everyday functioning
KW - norm scores
KW - results interpretation
U2 - 10.1017/S1355617724000031
DO - 10.1017/S1355617724000031
M3 - Article
SN - 1469-7661
SP - 1
EP - 6
JO - Journal of the International Neuropsychological Society : JINS
JF - Journal of the International Neuropsychological Society : JINS
ER -