Table 3 Father Engagement Interview Themes and Illustrative Quotes Mapped to CFIR Domains and Impact on Intervention Design: Characteristics of Individuals

Knowledge & Beliefs about the Intervention

Individuals’ attitudes toward and value placed on the intervention as well as familiarity with facts, truths, and principles related to the intervention

Fathers perceive the intervention as needed and valued, based on:

i. Their unique challenges preparing for and navigating fatherhood

ii. Lack of targeted resources to support them with challenges and engage in parenting

i.“Where the mother is carrying the baby for nine months, she's gonna get it, you know, it's just, like, a natural reaction. Whereas the father's, like, oh my God, I have a new child. What do I do?”; “Anything I receive on becoming a dad, any advice. It just continues to get more difficult.”

ii. “So many things are geared towards moms. Even when you read books, they are written for moms. It’s very clear. And that kind of makes you feel, as a father, like excluded.”; “I think having resources available for dads might make it more—might normalize more that dads are also involved in these decisions about parenting. That might increase dad involvement.”

-Additional support for conscious engagement of fathers through program materials

-Specific content on importance of fathers

Self-efficacy

Individual belief in their own capabilities to execute courses of action to achieve implementation goals

Fatherhood is a rewarding and empowering experience, instilling a sense of purpose and self-efficacy to provide for the child and partner

- “It's been a rewarding new experience watching a little family member grow and mature and flourish.”

- “I think the easiest thing is just being able to love my daughter. It's my first baby, and everything is all new to me, but it's—being a dad, I think just being able to love and hold and comfort my daughter is the easiest thing.”

- “What do I like most about being a dad? The feeling of knowing that I have someone to come home to and what I’m to doing to provide for them.”

- “The most important thing is just obviously I want her to be happy so whatever I can do to support her in that sense, I’m gonna do it.”

-Inclusion of developmental milestones and father-infant bonding within program materials

-Included quotes from interviewed fathers within intervention to normalize father involvement

Other Personal Attributes

A broad construct to include other personal traits such as tolerance of ambiguity, intellectual ability, motivation, values, competence, capacity, and learning style

Additional personal attributes relevant to the intervention:

i. Effects of fatherhood on father’s own health

ii. Fathers’ perceived Parenting roles (day-to-day child-care, emotional support, and practical support)

i. “I have less time for gym or exercise. Not as much time as I used to have.”; “Taking care of yourself during that period is often hard because you’re just—that’s a secondary consideration, so I didn’t sleep much. I was eating at weird times. I was eating weird foods. Taking care of yourself was harder than taking care of your kid, actually.”

ii. “Parenting is a two-person job. Just’cause your wife’s breastfeeding doesn’t mean you’re not involved in the nutrition of your child. Yeah, the earlier you’re involved, the happier you’ll be.”; “Just making sure that she’s healthy, so making sure that she’s developing, getting bigger and eating and monitoring to make sure she doesn’t have a fever.”; “I do a lot of the day-to-day on the home, everything around the home, cooking, cleaning…Mine’s more home and home maintenance, day-to-day maintenance.”; “A lot of it was just being proactive on all sorts of responsibilities more broadly than baby care, doing shifts as night so Mom can get some sleep.”

-Supported focus on paternal health behaviors, specifically related to nutrition, sleep, physical activity

-Reinforced fathers’ role in infant caretaking