Table 2 Content of the online modules and assessments

1. Introduction and goals

The patient formulates positive and tangible goals, which consist of activities they want to do when no longer severely fatigued.

2. Sleep and rest

The patient makes a sleep schedule and keeps an online diary with sleep and wake times. A regular sleep–wake cycle and sleep hygiene are discussed. Instructions are given on how to improve these.

- Sickness Impact Profile (subscale sleep and rest) [46]

- Registration of bedtime, wake-up time and sleep during the day for seven consecutive days

3. Fatigue-related cognitions

Loss of control over fatigue symptoms and thoughts, fatigue catastrophizing and dysfunctional thoughts are assessed. The patient does exercises to address and change their dysfunctional thoughts and keeps an online diary about these thoughts. Patients learn to focus less on fatigue.

- Fatigue Catastrophizing Scale [47]

- Illness Management Questionnaire factor III [48]

- Self Efficacy Scale Fatigue [49]

4. Activity regulation

The patient with a ‘relatively active’ activity pattern learns to distribute activities more evenly. Then both ‘relatively active’ and ‘low active’ patients systematically increase their physical activity with a graded activity program with walking or cycling. They track their daily progress in an online diary. They learn how to solve problems with activity regulation. The module aims to change activity-impeding beliefs and increase the physical activity level of patients.

- With actigraphy (actometer around the ankle for 14 consecutive days) the level of activity is objectified [50]. The activity pattern will be rated as ‘Low active’ or ‘Relatively active’.

Submodule 4A: Regulation of social activities (optional)

The relationship between cancer, fatigue and a reduction of social activities as well as cognitions about social activities are assessed. The patient increases his/her social activity level.

- Sickness Impact Profile (indication for this optional submodule: score subscale social activities ≥ 100) [46]

Submodule 4B: Regulation of mental activities (optional)

The patient learns about cognitive deficits and how to deal with them. The patient increases their mental activity level.

- Checklist Individual Strength (indication for this optional submodule: score subscale concentration ≥ 18) [36]

Submodule 4C: Going back to work (optional)

The patient makes a plan to return to work or increase working hours.

(indication for this optional submodule: if the patient has set a goal to return to work or increase working hours)

5. Fear of disease progression (optional)

Thoughts and situations that trigger fear regarding the future or tumour growth are assessed. The patient learns to be more accepting towards anxious feelings and to handle these feelings with exercises based on detached mindfulness, meta-cognitive therapy and exposure.

- Fear of Progression Questionnaire (indication for the module: score ≥ 34) [51]

- Beck Anxiety Inventory (indication for the module: score ≥ 36) [52]

6. Social support (optional)

Reactions of the partner and significant others to fatigue are assessed. Perceived discrepancy between actual and desired social support, experiences with negative social interactions and unrealistic expectations of others are assessed. The goal of this module is to support emotional independence of others and to become more assertive, as far as fatigue is concerned.

- Social Support List, subscale discrepancy (indication for the module: score ≥ 50) and subscale negative interactions (indication for the module: score ≥ 14) [53]

7. Living with a brain tumour (optional)

This module focuses on uncertainty about the future and how one can deal with the fact that one has an incurable disease. Several elements from meaning-centred psychotherapy, well-being therapy and writing therapy are used to help the patients to deal with the disease trajectory.

- Illness Cognition Questionnaire, subscale acceptance (indication for the module: score ≤ 12) and subscale helplessness (indication for the module: score ≥ 14) [54]

- Impact Event Scale, subscale avoidance (indication for the module: score ≥ 10) and subscale intrusion (indication for the module: score ≥ 10) [55]

8. Realizing goals

The patient looks back at the goals set in the first module and makes a plan to realize these goals. The intervention is evaluated.