The Strengths and Difficulties Questionnaire (SDQ) is a 25-item questionnaire that assesses child behavior. Items are rated on a 3-point scale and responses range from 0 ("Not true") to 2 ("Certainly true"). Some items are reverse-scored. Items are summed to yield 5 subscales: Emotional Problems, Conduct Problems, Hyperactivity, Peer Problems, and Prosocial (ranges 0 -10). A total score (range 0-40) is calculated using the sum of all the subscales, except Prosocial. Higher scores in each subscale and the total score indicate more child behavior problems.

The Parental Stress Scale is an 18-item questionnaire that assesses parental stress relating to parental sensitivity to the child, child behavior, and quality of the parent-child relationship. Items are rated on a 5-point scale, ranging from 1 ("Strongly disagree") to 5 ("Strongly agree"). Some items are reverse-scored. Items are summed to yield a total score (range 18-90), with higher scores indicating higher levels of parental stress.

The Group Environment Scale is a 25-item measure that assesses the dimensions of intervention group environments. Items are rated on a 5-point scale, with responses ranging from 1 ("Strongly disagree") to 5 ("Strongly agree"). Items are averaged to yield three subscales: Cohesiveness, Implementation and Preparedness, and Counterproductive Activity. Higher scores on the Cohesiveness Scale (range 1-5) indicate more group cohesiveness. Higher scores on the Implementation and Preparedness Scale (range 1-5) indicate greater group implementation quality. Higher scores on the Counterproductive Activity Scale (range 1-5) indicate more counterproductive group activities.

The Perceived Stress Scale is a 14-item self-report measure of how unpredictable, uncontrollable, and overloaded individuals find their life circumstances. All items are rated on a 5-point scale, ranging from 0 ("Never") to 4 ("very often"). Some items are reverse-scored. Responses are summed to yield a total score (range 0 - 56), with higher scores indicating greater perceived stress.

The Child Adjustment & Parent Efficacy Scale, Total Intensity subscale is a 27-item measure of child behavior and emotional problems. Item responses are rated on a 4-point scale, ranging from 0 ("Not true of my child at all") to 3 ("True of my child very much"/"Most of the time"). Twenty-four items are summed to yield a Behavior Problems score (range 0-72), and three items are summed to yield an Emotional Problems score (range 0-9). Behavioral and Emotional Problems scores can be summed for a Total Intensity score (range 0-81). Higher scores indicate a higher level of problems.

The Parenting Sense of Competence Scale is a 17-item questionnaire that measures overall parenting satisfaction and competence. Items are measured on a 6-point scale, with responses ranging from 1 ("Strongly disagree") to 6 ("Strongly agree"). Some items are reverse-scored. Items are summed to yield a total scale (range 17-102) and two subscales: parental self-efficacy (range 8-48) and parental satisfaction (range 9-54). Higher scores indicate higher levels of parental self-efficacy and parental satisfaction.

The Eyberg Child Behavior Inventory, a 36-item measure that assesses child behavior problems. Each item has 2 parts that make up 2 subscales: Intensity and Problem. Intensity items are rated on a 7-point scale, from 1 (Never) to 7 (Always), and Problem items are Yes/No responses. Items from each scale are summed to yield raw scores and converted to T-scores (M=50, SD=10). Higher Intensity scores indicate more frequent displays of the child behaviors, and higher Problem scores indicate the parent perceives the behaviors as more problematic. T-scores above 60 indicate elevated behavior problems.

The Parental Stress Scale is an 18-item questionnaire that assesses parental stress relating to parental sensitivity to the child, child behavior, and quality of the parent-child relationship. Items are rated on a 5-point scale, ranging from 1 ("Strongly disagree") to 5 ("Strongly agree"). Some items are reverse-scored. Items are summed to yield a total score (range 18-90), with higher scores indicating higher levels of parental stress.

The Child Adjustment & Parent Efficacy Scale, Total Intensity subscale is a 27-item measure of child behavior and emotional problems. Item responses are rated on a 4-point scale, ranging from 0 ("Not true of my child at all") to 3 ("True of my child very much"/"Most of the time"). Twenty-four items are summed to yield a Behavior Problems score (range 0-72), and three items are summed to yield an Emotional Problems score (range 0-9). Behavioral and Emotional Problems scores can be summed for a Total Intensity score (range 0-81). Higher scores indicate a higher level of problems.

N = 16 participants completed The Child Adjustment & Parent Efficacy Scale at Pre Intervention and n = 10 participants completed The Child Adjustment & Parent Efficacy Scale at 18 Weeks.

The Parenting Sense of Competence Scale is a 17-item questionnaire that measures overall parenting satisfaction and competence. Items are measured on a 6-point scale, with responses ranging from 1 ("Strongly disagree") to 6 ("Strongly agree"). Some items are reverse-scored. Items are summed to yield a total scale (range 17-102) and two subscales: parental self-efficacy (range 8-48) and parental satisfaction (range 9-54). Higher scores indicate higher levels of parental self-efficacy and parental satisfaction.

N = 16 participants completed the Parenting Sense of Competence Scale at Pre Intervention and n = 10 participants completed the Parenting Sense of Competence Scale at 18 Weeks

The Eyberg Child Behavior Inventory, a 36-item measure that assesses child behavior problems. Each item has 2 parts that make up 2 subscales: Intensity and Problem. Intensity items are rated on a 7-point scale, from 1 (Never) to 7 (Always), and Problem items are Yes/No responses. Items from each scale are summed to yield raw scores and converted to T-scores (M=50, SD=10). Higher Intensity scores indicate more frequent displays of the child behaviors, and higher Problem scores indicate the parent perceives the behaviors as more problematic. T-scores above 60 indicate elevated behavior problems.

N = 16 participants completed The Eyberg Child Behavior Inventory at Pre Intervention and n = 10 participants completed The Eyberg Child Behavior Inventory at 18 Weeks.

The Strengths and Difficulties Questionnaire (SDQ) is a 25-item questionnaire that assesses child behavior. Items are rated on a 3-point scale and responses range from 0 ("Not true") to 2 ("Certainly true"). Some items are reverse-scored. Items are summed to yield 5 subscales: Emotional Problems, Conduct Problems, Hyperactivity, Peer Problems, and Prosocial (ranges 0 -10). A total score (range 0-40) is calculated using the sum of all the subscales, except Prosocial. Higher scores in each subscale and the total score indicate more child behavior problems.

N = 10 participants completed The Strengths and Difficulties Questionnaire at 18 Weeks.

The Parental Stress Scale is an 18-item questionnaire that assesses parental stress relating to parental sensitivity to the child, child behavior, and quality of the parent-child relationship. Items are rated on a 5-point scale, ranging from 1 ("Strongly disagree") to 5 ("Strongly agree"). Some items are reverse-scored. Items are summed to yield a total score (range 18-90), with higher scores indicating higher levels of parental stress.

N = 16 participants completed The Parental Stress Scale at Pre Intervention and n = 10 participants completed The Parental Stress Scale at 18 Weeks.

The Group Environment Scale is a 25-item measure that assesses the dimensions of intervention group environments. Items are rated on a 5-point scale, with responses ranging from 1 ("Strongly disagree") to 5 ("Strongly agree"). Items are averaged to yield three subscales: Cohesiveness, Implementation and Preparedness, and Counterproductive Activity. Higher scores on the Cohesiveness Scale (range 1-5) indicate more group cohesiveness. Higher scores on the Implementation and Preparedness Scale (range 1-5) indicate greater group implementation quality. Higher scores on the Counterproductive Activity Scale (range 1-5) indicate more counterproductive group activities.

N = 2 participants completed The Group Environment Scale at Week 7, n = 4 participants completed The Group Environment Scale at Week 11, and n = 7 participants completed The Group Environment Scale at Week 19.