In addition to these general issues relating to the measurement of QoL in children there are issues which are
more specifically related to mental health problems in
children. Mental health disorders will interact in complex
ways with QoL. Mental health difficulties impact on a
person’s capacity to engage effectively in daily activities
and this can have knock-on consequences for their general
sense of well-being. A reduced sense of well-being can also
impact on mental health by, for example, further lowering
mood. In childhood, the effects of mental health difficulties
on QoL are perhaps most obvious in the more severe or
extreme forms of mental health problem (e.g. autism) or
those that impact directly on an individual’s sense of self
worth (e.g. anxiety and depression). However, there is
growing evidence that the, so called, externalizing disorders such as oppositional defiant disorder and attention
deficit/hyperactivity disorder (ADHD) also substantially
reduce the QoL of children and young people in terms of
their subjective sense of wellbeing and their capacity for
everyday functioning.