Cunningham 1995.

Methods	Parallel randomised controlled trial.
Participants	Participants: 150 volunteer parents of pre‐school children with behaviour problems. Sex: both mothers or fathers (no further information). Age of parents: mean 54.2 years, SD 4.4 (community); mean 52.3 years, SD 4.6 (clinic); mean 54.1 years, SD 4.5 (control). Unit of allocation: individual participant. Number randomised: 150 (48 group‐based; 46 individual‐based; 56 control). Number used in analysis: 78 (36 group‐based; 42 control). Country & setting: Canada; single‐site; recruited from community and outpatient settings; delivered in the community (group intervention) and in an outpatient clinic (individual intervention). Inclusion criteria: parents with children rated at least 1.5 standard deviations above the mean for age and sex on Home Situations Questionnaire. Exclusion criteria: not stated. Ethnicity: 83% Canadian born, 17% immigrants (group intervention); 82% Canadian born, 18% immigrants (control). Baseline characteristics: 83 % two parents, 50% boys (group intervention); 71.4% two parents, 46.4% boys (control).
Interventions	Three conditions: Cognitive‐behavioural parenting programme; wait‐list control; parent programme delivered on a individual basis. Duration of intervention: 11 to 12 weeks. Length of follow‐up: 6‐months.
Outcomes	Depressive symptoms (Beck Depression Inventory). Confidence (Parenting Sense of Competence Scale).
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Trial investigators report that "those returning questionnaires above 90th percentile were block randomly assigned to one of three treatment conditions" (Abstract). Sequence generation process was not described, but information from trial investigator (email from C.Cunningham to NH on 22 Oct 2010) indicates that a random numbers table was used.
Allocation concealment (selection bias)	Low risk	Trial investigators report that "sealed questionnaire were returned to the school and forwarded unopened to the research team" (page 1143). Review authors judged that allocation was probably adequately concealed.
Blinding (performance bias and detection bias) Participants	High risk	Review authors judge 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	High risk	Design of study means personnel would be aware which groups had been assigned to an intervention condition.
Blinding (performance bias and detection bias) Outcome assessors	Low risk	Trial investigators report "data were collected during home visits by research assistants who were uninformed of the family's condition" (page 1145). Review authors judge that outcome assessors were blind to allocation status of participants.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Trial investigators report "of the 150 participants beginning the trial, 36 (24%) failed to complete the 6 month follow‐up.  The number of dropouts in the respective conditions did not differ significantly" (page 1148). Missing outcome data balanced in numbers across intervention groups. Information from trial investigator (email from C.Cunningham to NH on 22 Oct 2010) indicates that the missing data were balanced between conditions and reflected dropout from the study.
Selective reporting (reporting bias)	Low risk	Review authors judge that the published report includes all expected outcomes, including those that were pre‐specified.
Other bias	Low risk	The study appears to be free of other sources of bias.