Bradley 2003.

Methods	Parallel randomised controlled trial.
Participants	Participants: parents of preschoolers with behavioural problems, recruited through advertisements placed in community locations. Sex: 184 mothers; 14 fathers. Age of parents: mean 35.20 years (SD 5.51) intervention; mean 35.88 years (SD 5.73) control. Unit of allocation: individual participant. Number randomised: 198 (89 intervention; 109 control). Number used in analysis: number available for analysis n=174 (81 intervention; 93 control)*. Country & setting: Canada; multi‐site (number unclear); recruited from community settings; intervention delivered in the community. Inclusion criteria: parents experiencing problems managing the behaviour of their 3 or 4 year old children. Exclusion criteria: not stated. Ethnicity: not stated. Baseline characteristics: described as largely middle‐class parents; >80% had post‐secondary education; significantly more boys (121) than girls (77); no significant differences between experimental and control groups on age of parents, age of child, or intactness of family.
Interventions	Two conditions: Psychoeducational programme with videotape modelling (behavioural parenting programme); wait‐list control. Duration of intervention: 7 weeks. Length of follow‐up: 12 months.
Outcomes	Depressive symptoms (Brief Symptom Inventory)*. Stress (Brief Symptom Inventory)*.
Notes	*Insufficient data to calculate effect sizes. Clarification was requested from the trial investigators but no further information was available at the time this review was prepared.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Information reported insufficient for a judgement to be made. We requested clarification from the trial investigators, but no further information was available at the time this review was prepared.
Allocation concealment (selection bias)	Unclear risk	Information reported insufficient for a judgement to be made. We requested clarification from the trial investigators, but no further information was available at the time this review was prepared.
Blinding (performance bias and detection bias) Participants	High risk	Review authors judged that it would not be possible to fully blind participants in this type of study, and found no indication of any specific additional measures taken to reduce the risk of bias that might result from differential behaviours by participants.
Blinding (performance bias and detection bias) Personnel	Unclear risk	Information reported insufficient for a judgement to be made. We requested clarification from the trial investigators, but no further information was available at the time this review was prepared.
Blinding (performance bias and detection bias) Outcome assessors	Unclear risk	Information reported insufficient for a judgement to be made. We requested clarification from the trial investigators, but no further information was available at the time this review was prepared.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Data for 8/89 (9%) missing from the intervention condition, and for 16/89 (15%) from the control condition. Reasons for dropout not given. Overall attrition was 11.8% at post‐intervention. Review authors considered the numbers of and reasons for missing data reasonably likely to be balanced across the treatment conditions.
Selective reporting (reporting bias)	High risk	Investigators do not report endpoint / follow‐up data for depressive symptoms from the BSI subscale outcomes. Clarification has been requested, but the trial investigators (email from SJ Bradley to CB on 07/07/10) states that they "are unable to find the data".
Other bias	Low risk	The study appeared to be free of other sources of bias.