What this trial measures

• Change from Baseline to Post-Treatment in Parenting StressThe PSI-SF will be administered at baseline (approximately 0-2 weeks pre-treatment) and at post-treatment (after completion of Session 12, approximately 15 weeks after baseline measurement).

  Change in parenting stress from baseline will be measured using the total score on a self-reported questionnaire: the 36-item Parenting Stress Index, Short-Form (PSI-SF; Abidin, 2012). Item responses are rated on a 5-point Likert scale ranging from 1 (Strongly Disagree) to 5 (Strongly Agree). Scores are summed to generate a total score ranging from 36 to 180. Raw scores can be converted to percentile based on a normed sample. Higher raw and percentile scores indicate higher levels of parenting stress. Scores falling between the 16th and 84th percentiles are considered within the normal range of parenting stress, scores between the 85th and 89th percentiles are considered high, and scores at the 90th percentile and above are considered in the clinically significant range.

• Change from Baseline to Post-Treatment in Parental Reflective FunctioningThe PRFQ will be administered at baseline (approximately 0-2 weeks pre-intervention) and at post-intervention (after completion of Session 12, approximately 15 weeks after baseline measurement).

  Change in parental reflective functioning from baseline will be measured using the 18-item Parental Reflective Functioning Questionnaire (PRFQ; Luyten et al., 2017). This measure assesses three dimensions of reflective functioning: Prementalizing Modes, Certainty about Mental States, and Interest and Curiosity about Mental States. Scores are measured using a 7-point Likert scale ranging from 1 (Strongly Disagree) to 7 (Strongly Agree) across three subscales, with higher scores indicating higher levels of that specific dimension. Subscale scores are calculated and reported as mean scores (range 6 to 42). Although clinical thresholds have not been established, adaptive reflective functioning is characterized by low Prementalizing Modes, mid-range Certainty about Mental States, and high Interest and Curiosity about Mental States.

• Change from Baseline to Post-Treatment in Restrictive EmotionalityThe Restrictive Emotionality Subscale of the MRNI-R will be administered at baseline (approximately 0-2 weeks pre-treatment) and at post-treatment (after completion of Session 12, approximately 15 weeks after baseline measurement)

  Change in restrictive emotionality from baseline will be measured using a subscale on a self-reported questionnaire: the Restrictive Emotionality subscale of the Male Role Norms Inventory-Revised (MRNI-R; Levant et al., 2007). The subscale consists of 8 items rated on a 7-point Likert-type scale ranging from 1 (Strongly Disagree) to 7 (Strongly Agree). A mean subscale score is calculated, with possible scores ranging from 8 to 56. Though threshold scores have not been established for the MRNI-R, higher subscale scores indicate greater endorsement of restrictive emotionality norms, reflecting beliefs emphasizing emotional control and limited emotional expression, whereas lower subscale scores indicate greater emotional openness and comfort with emotional expression.

• Change from First Session to Post-Treatment in Therapeutic Group ProcessesThe TFI-19 will be administered after participants attend their first group session (approximately 0-2 weeks after baseline measurement) and again at post-treatment (after completion of Session 12, approximately 15 weeks after baseline measurement).

  Changes in therapeutic group processes from after the first group session attended to post-intervention will be assessed using subscales from a self-report questionnaire, the revised Therapeutic Factors Inventory-19 (TFI-19; Joyce et al., 2011). Items are rated on a 7-point Likert scale ranging from 1 (strongly disagree) to 7 (strongly agree). Subscale scores are calculated as the mean of item ratings (mean score range: 1-7), with higher scores indicating stronger perceptions of the corresponding therapeutic factors within the CARE group. The four subscales include Instillation of Hope (4 items; score range: 4-28), Secure Emotional Expression (7 items; score range: 7-49), Awareness of Relational Impact (5 items; score range: 5-35), and Social Learning (3 items; score range: 3-21).

• Post-Treatment Ratings of FeasibilityThis survey will be administered at post-treatment (i.e., after completion of Session 12, approximately 15 weeks after baseline measurement).

  Intervention feasibility will be measured by Feasibility of Intervention Measure (FIM; Weiner et al., 2017). The FIM is a 4-item subscale that measures the extent to which a new treatment or innovation can be successfully used or carried out by the caregiver in this setting. All items are scored on a 5-point Likert scale, from 1 (Completely disagree) to 5 (Completely agree). Higher scores correlate with greater feasibility of the implementation of the intervention.

• Post-Treatment Ratings of AcceptabilityThis survey will be administered at post-treatment (i.e., after completion of Session 12, approximately 15 weeks after baseline measurement).

  Intervention acceptability will be measured by Acceptability of Intervention Measure (AIM; Weiner et al., 2017). The AIM is a 4-item subscale that measures the extent to which a new treatment or innovation is found to be acceptable by the caregiver within this setting. All items are scored on a 5-point Likert scale, from 1 (Completely disagree) to 5 (Completely agree). Higher scores correlate with greater acceptability of the intervention.

• Post-Treatment Ratings of AppropriatenessThis survey will be administered at post-treatment (i.e., after completion of Session 12, approximately 15 weeks after baseline measurement).

  Intervention appropriateness will be measured by Intervention Appropriateness Measure (IAM; Weiner et al., 2017). The IAM is a 4-item subscale that measures the extent to which a new treatment or innovation is deemed to be appropriate by the caregiver within this setting. All items are scored on a 5-point Likert scale, from 1 (Completely disagree) to 5 (Completely agree). Higher scores correlate with greater appropriateness of the intervention.

• Post-Treatment Ratings of Outcomes and FeedbackThis survey will be administered at post-treatment (i.e., after completion of Session 12, approximately 15 weeks after baseline measurement).

  Participants will complete a post-intervention feedback survey. Quantitative items include six 10-point Likert scale questions assessing caregivers' comfort with emotional expression in group, overall satisfaction, perceived helpfulness for caregivers' emotional well-being, perceived helpfulness for the caregiver-child relationship, perceived emotional challenge of participating in the group, and challenge attending sessions (min score = 1, not at all; max score = 10, extremely). Higher scores indicate greater improvement or acceptability, with the exception of items related to perceived challenge for which higher scores indicate lower feasibility and acceptability. Caregivers also rate change in comfort in expressing emotions relative to the start of the group on a 5-point Likert scale (min score = 1, much less comfortable; max score = 5, much more comfortable). Participants indicate whether they would recommend CARE to other male caregivers using a 2-point scale (1 = Yes, 0 = No).

• Post-Treatment Participant Group AttendanceTime Frame: This survey will be administered at post-treatment (i.e., after completion of Session 12, approximately 15 weeks after baseline measurement).

  Participant attendance will be tracked, and the average number of group sessions completed by participants at the end of the intervention will be summarized using the mean number of sessions attended.