Outcome measures to assess health fluctuations
dementia
EVENTS
The primary outcomes of this study are (i) the occurrence, frequency and intensity of health state fluctuations documented in the 14-day diary and by using the change in health states from day 1 to day 7 and day 7 to day 14 using the EQ-5D-5L index, the EQ-5D dimensions and the EQ-VAS, (ii) affected HRQoL dimensions, (iii) the underlying health events over time that could have affected patients' health, and (iv) the incorporation of recurrent health state fluctuations in the assessment of health today using the EQ-5D-5L.i. To assess the frequency and intensity of the health state fluctuation, caregivers document if patients' today's health is much (+2) or somewhat better today (+1), about the same (±0) today, or somewhat (−1) or much (−2) worse today compared to the day before. Also, a repeated administration of the EQ-5D-5L will also assess the health state fluctuation as a self- and proxy-rating at baseline (before starting the diary), seven days after starting the diary, and on the last day of the diary (day 14). The change in the EQ-5D-5L utilities, EQ-5D-5L level scores and level sum scores (LLS), and EQ-VAS scores from day 1 to day 7 and day 7 to day 14 can be used to assess the variability and reliability of each measure.ii. To assign health state fluctuations to specific health dimensions, we will use the health dimension of the diary and the assessment of EQ-5D-5L dimensions at baseline, seven, and 14 days. The caregiver will be instructed to document in the diary which dimensions could be assigned to the fluctuation of today's health state compared to the day before. We will use dimensions of the EQ-5D-5L and two other patient-reported outcomes measures (PROMs), the EQ Health and Wellbeing instrument (EQ-HWB) (iii. Caregivers will also be asked to document any health events that could have caused the health state fluctuations.iv. To evaluate the consideration of past health state fluctuations in the assessment of today's health, the EQ-5D-5L will be administered on day 14. Subsequently, the caregivers will be interviewed and asked whether or not recurrent health state fluctuations (if applicable) were considered in the assessment of health today using the EQ-5D-5L administered minutes before starting the interview. Furthermore, the caregiver will be asked to state what recall period would be more appropriate to assess HRQoL in people living with dementia more accurately.