Klosky 2007a.

Methods	Randomised controlled trial
Participants	Inclusion criteria: parents with a child aged 2–7 years diagnosed with a primary malignancy; English was primary language; no prior experience with external beam radiotherapy; who were functioning at the level in which the children could tolerate radiotherapy intervention. Exclusion criteria: not specified. Number randomised: 80 (41 intervention group, 39 control group). Follow‐up: until the final day of radiotherapy simulation (not further specified). Communication with authors revealed that this was, in most cases, approximately a 90‐minute interval between baseline and post assessment. Setting: radiotherapy outpatient clinic in the US.
Interventions	Intervention group: CBT package that included exposure to an interactive‐educational ActiMates Barney, an educational video in the clinic room including filmed modelling, and passive auditory distraction via Barney‐narrated stories delivered during the simulation procedure. Modified control group: similar intervention composed of exposure to non‐interactive children's control character (similar size, colour, and shape to Barney), an age‐appropriate cartoon video, and storied delivered via cassette tape during treatment.
Outcomes	Caregiver outcomes Anxiety (State‐Trait Anxiety Inventory) Opinions about efficacy of radiotherapy and aspects of the experimental conditions (study specific Parent Exit questionnaire) Patient outcomes Sedation (anaesthesia administered) Behavioural distress (Observation Scale of Behavioral Distress) Physiological arousal (heart rate) Anxiety (State‐Trait Anxiety Inventory)
Notes	Primary child outcomes were published previously (Klosky 2004; Klosky 2007b; Tyc 2002). 67% neuro‐oncology (80 participants, 41 intervention, 39 control. In total, 53 caregivers of people with brain tumours were included).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Not described in the report. Computer random number generator used (confirmed by authors).
Allocation concealment (selection bias)	Low risk	Not described in the report. Computer random number generator used (confirmed by authors).
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not described in the report. The authors explained that participants were not fully aware of study goals and would, therefore, not know whether they were assigned to the intervention or modified control group. However, they were not formally blinded.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Not described in the report. The authors could not remember exactly how data analysis was performed.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Not described in the report, authors confirmed that there was no attrition and all participants completed the outcome measures.
Selective reporting (reporting bias)	Unclear risk	There was no published study protocol. All outcomes in the manuscript were reported on; other (patient‐focused) outcomes were published elsewhere.