Table 1 Inclusion and exclusion criteria

(1) Histologically confirmed diffuse glioma WHO grade 2, 3 or 4

(1) Treatable somatic cause that could explain the presence of severe fatigue (other than the underlying disease and its treatment)

(2) Age ≥ 18 years

(2) Primary sleep disorders previously diagnosed by a physician

(3) CIS subscale fatigue severity  ≥ 35 (36)

(3) Current treatment by a psychiatrist or psychologist for a psychiatric disorder

(4) Expected survival of at least three months, as determined by treating clinician

(4) Suspected depression by screening with BDI-PC≥4 [37] and The Mini-International Neuropsychiatric Interview depressive disorder [38]

(5) No oncological treatment for at least two months prior to inclusion

(5) Pregnancy or given birth in the past three months

(6) No signs of radiological or clinical tumour progression at the time of inclusion

(6) Pharmacological treatment for fatigue, started in the past three months

(7) Able to speak, read and write Dutch

(7) Karnofsky Performance Status score <70 [39]

(8) Access and ability to use the internet

(8) Corticosteroid use

(9) Written informed consent