Wakefield 2016.

Methods	Randomised controlled trial
Participants	Inclusion criteria: parents of children who had finished cancer treatment were eligible if they: had a child aged ≤ 15 who had completed cancer treatment with curative intent in the past 5 years; were able to read English; were able to access the Internet in a private location. Exclusion criteria: parents could not participate if they: had insufficient English skills; were experiencing extreme anxiety or depression; endorsed current symptoms of psychosis or substance abuse; had a child who was on active treatment, had relapsed, or was in palliative care Number randomised: 56 consented and randomised (before baseline), 9 dropped out before baseline assessment. 25 intervention group; 22 control group. Follow‐up: baseline, 2 weeks, 6 months Setting: children's hospital in Australia
Interventions	Intervention group: Cascade is a manualised programme consisting of 3 weekly 120‐minute online sessions delivered by a psychologist through WebEx. Driven by the theoretical models, Cascade targets intra‐ and interpersonal psychological processes important to adaptation in the context of illness (e.g. acceptance of uncertainty; practical problem solving; mobilising social support resources). CBT strategies were used to target these core mechanisms of change. Topic areas were derived from a previous study (but not specified in paper). After each session, parents would get homework assignments to practice. Control group: waiting list control group, parents could participate in Cascade intervention after 6 months.
Outcomes	Feasibility (80% completion rate would indicate feasibility; preference for length of intervention and questionnaires; clinical impressions and technical difficulties) Acceptability (California Psychotherapy Alliance Scale‐Group short version and Youth Satisfaction Questionnaire QoL (QoL – Family Caregiver Tool) Family functioning (McMaster Family Assessment Device)
Notes	28% neuro‐oncology (47 participants; 25 intervention group, 22 control group. In total, 13 caregivers of brain tumour patients were included).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Independent personnel used an electronic randomiser to allocate participants to Cascade or waiting list.
Allocation concealment (selection bias)	Low risk	Independent personnel used an electronic randomiser to allocate participants to Cascade or waiting list.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not possible due to nature of intervention.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	The statistician remained blinded until all analyses were completed.
Incomplete outcome data (attrition bias) All outcomes	High risk	Only participants with all 3 assessments completed were included in analysis of psychosocial outcomes (17% dropout at 6 months in intervention group; 27% dropout in waiting list control group). Unclear what reasons were.
Selective reporting (reporting bias)	Unclear risk	There was no published study protocol. All outcomes in the manuscript were reported on.

BPI: Brief Psychological Intervention; CBT: cognitive behavioural therapy; COPE: Creativity, Optimism, Planning, Expert Information; EORTC BN20: European Organization for Research and Treatment of Cancer Brain Cancer Module; EQ‐5D: EuroQol; MOS: Medical Outcome Study; NEO: Neuroticism‐Extraversion‐Openness; QoL: quality of life; SF‐36: 36‐item Short Form; WHO: World Health Organization.