The Scale of Instantaneous Wellbeing: Validity in a Population with Major Neurocognitive Disorders

The quality of life (QoL) of people with a neurodegenerative pathology is a major issue in the absence of curative treatment. However, validated tools, suitable for patients with major neurocognitive disorders at a severe stage are rare and time-consuming in routine. The aim of this study is to analyze the validity of convergence and the reliability over time of a visual analog scale of well-being named EVIBE (Échelle d'évaluation instantanée de bien-être). The correlation between the EVIBE and another quality of life scale, the Qol-Ad was studied. The correlation with other scales expected to vary with QoL was also studied with the EQ-5D for the measurement of the state of health felt and the NPI-ES for the measurement of behavioral disorders. The EVIBE was administered twice, a few minutes apart, to measure its reliability over time. One hundred and thirty-five patients with Alzheimer's disease or a related disorder were recruited. The results indicated a significant correlation with Qol-AD (r=0.54, p< 0.001). The correlation remained significant when the Mini mental state examination was less than 10 (r=0.39, p=0.05). Correlations between EVIBE and EQ-5D and NPI-ES indicated more mixed results with significant correlation only for the analog part of the EQ-5D (r=0.34, p=0.007). The comparison between the two EVIBEs a few minutes apart showed a satisfactory agreement (r=0.52, p> 0.001). This study shows that EVIBE present a good convergence validity and a good reliability over time to measure the QoL of patients with neurodegenerative pathology even at severe stages of the disease. The scale allows a direct and rapid assessment of the QoL of patients in routine.