Comparison of Two Modes of Administration of the IADL Questionnaire

In France, about 1 million people 65 and older are diagnosed with dementia syndrome characterized by cognitive decline and impairment of functional capacity. The assessment of the level of functional autonomy is therefore an essential step in monitoring patients in Memory Clinic and can be estimated by the Lawton IADL questionnaire, assessing the patients' ability to perform daily tasks.

In the Memory Clinic, the first estimate of the level of patient autonomy is achieved during a face-to-face interview between their primary caregiver and a nurse, using the IADL questionnaire. This assessment should be renewed every year. The IADL questionnaire is part of the information that the memories consultations shall transmit to the Alzheimer's National Bank (BNA).

However, current practice has shown that the systematic collection is problematic in the organization of Memory Clinic. It is thus expected to collect this questionnaire by phone in order to measure changes in the level of autonomy during the disease, and improve the completeness of this collection. A study is conducted with the main objective to measure the reliability of the assessment of IADL questionnaires conducted during a telephone interview with the caregiver of the patient, in comparison to the reference mode: the face-to-face interview with the caregiver.

Materials and methods The experimental design of the study will be a randomized crossover trial (crossover), including 394 patients divided into two branches. In the first part, the collection of the IADL questionnaire will be performed according to the reference method in the consultation (face-to-face interview with the nurse), the measurement will be repeated at 1 month intervals by phone. In the second part the sequence of execution modes will be reversed. The reliability of the measurement of the level of autonomy will be studied by comparing repeated measurements based on handover modes. The correspondence between the repeated measures will also be considered in terms of patient characteristics. The feasibility of administration of the questionnaire by phone mode will be evaluated.

Expected results The mode of administration by phone should allow to obtain a reliable measurement of the level of patient autonomy when the administration is carried out in a standardized way. The study should also identify patients and situations for which this method of administration by phone may be appropriate.