How wellbeing and malaise are assessed
The World Health Organisation assesses mental health by counting the number of manifestations associated with various disorders. We all react to everyday life events, which is normal. But when they become frequent, lasting and have consequences (distress, functional impairment) these reactions become inappropriate.
For example, anyone happens to be sad one day or another. This comes with a sad or bad mood, feeling like crying, energy loss, yearning loss, pleasure loss, thinking about death or dying, etc. When these manifestations are numerous, this is called depression. Severity increases with their number.