OBJECTIVE: While prolonged fatigue states are frequently comorbid
with other forms of distress, they are now the subject of
independent aetiological and treatment research. The objective
of this study was to use principal component analysis to
clarify the relationships between proposed measures of
prolonged fatigue and anxiety and depression in data obtained
from patients attending primary care.
measures of prolonged fatigue and psychological distress
(anxiety and depression) were administered to consecutive
ambulatory care patients attending primary care.
from 1593 subjects were obtained. A two-factor principal
component solution (varimax rotation) demonstrated a clear
separation between fatigue-related items (Cronbach’s alpha =
0.81) as compared with those items describing anxiety and/or
depression (Cronbach’s alpha = 0.95). A four-factor solution
produced similar results with two factors describing general
psychological distress (contrasting anxiety and depression),
with two other factors describing the profiles of mental and
CONCLUSIONS: The results lend weight to the
argument that prolonged fatigue states can be measured
independently of conventional notions of anxiety and
depression in patients attending primary care.
Epidemiological, aetiological and treatment research in
psychiatry may need to focus greater attention on such
prolonged fatigue states.
Koschera A, Hickie I, Hadzi-Pavlovic D, Wilson A, Lloyd A