Christian 2006.

Study characteristics
Methods	RCT. 2‐group, experimental, repeated‐measures design (baseline, 3, 6, and 9 months intervals) with randomly assigned participants to intervention and usual care group. Hypothesis: children with CF who receive the intervention will improve significantly on 3 parameters (psychosocial adjustment, functional health status, physiologic health) over the time compared to children who received usual care.
Participants	Population of interest: N = 128. Number of randomised participants: N = 116. Control group 'usual care': N = 58. Intervention group 'educational problem‐solving and social skills intervention': N = 58. Included children with CF aged 8 ‐ 12 years receiving care from one of four CF centres in North Carolina (USA).
Interventions	Educational problem‐solving and social skills intervention (N = 58) versus usual care (N = 58). Children in the problem‐solving group received individual, tailored intervention during one home visit and a structured group session (conducted approximately 2 weeks after individual home visit). Intervention was designed to support children (8 ‐ 12years) with the following specific problems: 1. finding out about the CF diagnosis; 2. explaining CF‐related differences; 3. dealing with teasing about CF; 4. keeping up with peers during physical activity. The intervention contains 4 modules. In every module there was a focus on one of the 4 mentioned areas of problems (1‐4). The intervention team received detailed information about the intervention protocol and was trained and supervised conducting the intervention.
Outcomes	5 questionnaires which are developed for children were read aloud by research assistant to the children. The following questionnaires were used to the assess different constructs: Psychosocial adjustment was assessed by: ‐ Perceived Illness Experience Scale (35 items); ‐ Children's Loneliness Scale (16 items); ‐ Social Support Scale for Children (16 items); ‐ Self‐Perception Profile for Children (30 items). Functional Health Status was assessed by: ‐ Functional Disability Inventory (15 items). Physiolgical Health Status: ‐ Pulmonary function (FEV1). ‐ Height and weight. ‐ BMI.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The authors describe that the children were randomly assigned to the intervention and control group "using a computer‐generated randomization plan". (Christian 2006, p. 302)
Allocation concealment (selection bias)	Low risk	Assignment could not been foreseen by participants and investigators enrolling participants due to a computer‐generated randomisation plan.
Blinding (performance bias and detection bias) All outcomes	Low risk	The authors state that "group assignments were unknown to the CF clinics and research assessment team". (Christian 2006; p. 302)
Incomplete outcome data (attrition bias) All outcomes	Low risk	The authors stated that "all children completed the baseline and 3 follow‐up assessments" (Christian 2006, p.301). That means that there was no attrition or loss of any participant during the study and follow‐up period.
Selective reporting (reporting bias)	Unclear risk	All outcomes mentioned in the published records are reported. It is unclear if additional outcomes were pre‐specified in the study protocol but not reported.