Family focused cognitive behaviour therapy versus behaviourally oriented psycho-education for chronic fatigue syndrome in 11 to 18 year olds: a randomised controlled treatment trial

School attendance expressed as a percentage of what was expected.

As a secondary outcome school attendance was dichotomised with a good outcome set at 70% or more, as at this age many healthy adolescents are not attending school or college full time. The following were recorded at six months:
1. Fatigue: Chalder Fatigue Scale - internal consistency in this sample was excellent with a Chronbach’s alpha of 0.89
2. Functional impairment: physical functioning subscale of the 36-item Short Form health survey (SF-36) (range 0 to 100 higher scores denoting better health) - this measure is valid and reliable and has been used in adolescents with CFS
3. Degree to which fatigue interfered with adolescent’s life: Social Adjustment Scale - Chronbach’s alpha was 0.91
4. Emotional and social responses: adolescents and their mothers completed the strengths and difficulties questionnaire - this measure has been shown to be valid and reliable in a number of studies
5. Global improvement and satisfaction: Global Outcome Scales - an assessor, blind to the group in which participants were randomised, carried out a semi-structured interview with the adolescent and rated degree of improvement in fatigue and disability on a nine-point scale from “much better” to “much worse”