“…For this reason, self-rating of the QoL is often replaced by proxy rating. However, it has been shown that there could be differences on QoL ratings between patients, caregivers and theoretical models [ 48 ]. Caregivers consistently rate the patient’s QoL lower [ 14 ],[ 49 ], not only because of cognitive function [ 22 ],[ 50 ],[ 51 ] but also because of the caregiver’s burden or depression [ 22 ],[ 49 ],[ 50 ],[ 52 ],[ 53 ] and the patient’s depressive symptoms [ 54 ].…”