van den Hoofdakker 2007

Methods	Design: Randomised controlled trial
Participants	Participants: Children who met DSM‐IV criteria for ADHD (full scale IQ of the WISC‐III‐R for children under 6). Age: 4‐12 (mean age 7.4, SD = 1.9). Gender: 76 boys, 20 girls. Number: 96. Setting: Mental health outpatient clinics, the Netherlands. Inclusion criteria: Meet DSM‐IV criteria for ADHD, IQ>80 (Full Scale IQ of the WISC‐III‐R, for children under the age of 6 years the Full Scale IQ of the QWPPSI‐R), age between 4‐12 years, both parents (if present) willing to participate in the BPT program. Exclusion criteria
Interventions	Behavioural Parent Training + Routine Clinical Care: Manual based parent training consisted of 12 x 120 minute group sessions over 5 months for 6 children's parents at a time. Sessions led by two psychologists, specific target behaviours were established for each child. Most techniques were drawn from Barkley (1987) and Forehand & McHahon (1981). Parenting skills addressed were: structuring the environment, setting rules, giving instructions, anticipating misbehaviors, communicating, reinforcing positive behaviour, ignoring, employing punishment, and implementing a token system. Psychoeducation and restructuring of parental cognitions were also important elements. Homework assignments were given and parents read chapters from a specially written book by van der Veen‐Mulders (2001). Each week parents practiced the skills and wrote reports after the exercises. Follow up assessment 25 weeks post‐intervention. Routine Clinical Care: Carried out by four experienced senior child and adolescent psychiatrists. They provided care as usual including supportive counselling, psychoeducation, pharmacotherapy, and crisis management whenever necessary. Checkups were usually every 3‐6 months. Parents were given the group parent training after all data had been collected.
Outcomes	Primary outcomes: Change in the child's ADHD‐symptom‐related behaviour in home setting: The ADHD Index subscale of the Conners' parent Rating Scale‐Revised Short Form (CPRS‐R‐S) (Conners 2001). Changes in the child's general behaviour: Externalizing and Internalizing subscales of the Dutch version of the Child Behaviour checklist (CBCL) (Achenbach 1991). Secondary outcomes: Parental Stress: Parenting Stress Index (Abidin, 1983).
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "randomized block design" (p.1265). No method specified.
Allocation concealment (selection bias)	Unclear risk	Not described.
Blinding (performance bias and detection bias) of participants?	High risk	Participants cannot be blinded to intervention.
Blinding (performance bias and detection bias) of those delivering intervention?	High risk	Those delivering intervention cannot be blinded.
Blinding (performance bias and detection bias) of outcome assessors?	Unclear risk	Blinding of outcome assessors not mentioned.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Investigators described using intention‐to‐treat analysis for missing data (using a last‐observation‐carried‐forward method)
Selective reporting (reporting bias)	High risk	All outcomes prospectively stated have been reported. However, they collected information from both parents separately but state that: "In this study we analyzed the data from the mothers" (p 1266).
Other bias	Low risk	Study appears to be free from other sources of bias.