The slogan “If we change the beginning of the story, we change the whole story” (World Health Organization et al., 2018) highlights the priority and urgency of investing in early childhood development. Investments in early childhood positively impact children’s lives and enhance human capital, supporting society’s development and bringing lifelong benefits (Britto et al., 2017; Daelmans et al., 2015).

The Nurturing Care Framework is a roadmap that supports countries in developing and implementing evidence-based actions to ensure opportunities for young children’s development and well-being (World Health Organization et al., 2018). In this sense, a stable familial environment sensitive to children’s needs that provides protection, opportunities for learning, and responsive interactions should be at the core of interventions targeting child development and health outcomes (Bornstein et al., 2022; Britto et al., 2017; Jeong et al., 2022).

Globally, several interventions have been proposed to improve early childhood development (Bornstein et al., 2022; Britto et al., 2017; Britto et al., 2015; Jeong et al., 2021). Beyond cognitive stimulation, intergenerational approaches supporting caregivers’ parenting skills, such as parent-child responsive interaction and positive parenting, are powerful, longstanding, and cost-benefit strategies for promoting child development (Britto et al., 2017; Fisher et al., 2016; Jeong et al., 2021; Shonkoff & Fisher, 2013; Tereno et al., 2019).

In early childhood, mother-child interactions are particularly important for establishing secure attachment, preventing behavioral and mental disorders, and developing resilience in the face of adverse situations throughout life (Bernier et al., 2016; Goldblatt et al., 2014; Vu et al., 2015). Mother-child interactions can be positively affected by parenting interventions aimed at improving and supporting positive parenting behaviors, knowledge, beliefs, attitudes, and practices, consequently promoting children’s socio-emotional, cognitive, and language development and self-regulation (Bornstein et al., 2022; Britto et al., 2017; Britto et al., 2015; Fisher et al., 2016; Jeong et al., 2021; Obradovic´ et al., 2016). Moreover, the quality of mother-child interactions can positively and negatively affect cognitive, language, and social outcomes during the first year of life (Rocha et al., 2020).

Despite the considerable heterogeneity across models, contents, and measures, a convergent result of previous reviews is that preventive interventions improve parenting outcomes such as parenting knowledge and practices (Britto et al., 2015; Jeong et al., 2021; Jeong et al., 2018; Morrison et al., 2014), psychosocial outcomes (Barlow et al., 2011; Britto et al., 2017; Britto et al., 2015), and positive parent-child interactions (Jeong et al., 2021; Jeong et al., 2018; Letourneau et al., 2015; Shah et al., 2016).

Among preventive interventions, home-visiting programs are considered the oldest and most widely used to promote positive parenting (Bakermans-Kranenburg et al., 2003; Britto et al., 2015; Duffee et al., 2017; Finello et al., 2016; Jeong et al., 2021; Jeong et al., 2018; Morrison et al., 2014; Mountain et al., 2017). Home visits provide support and information that enable families and caregivers to provide nurturing care for children (World Health Organization et al., 2018; World Health Organization & UNICEF, 2022). On this topic, in their meta-analysis, Jeong et al. (2021) found that from 102 randomized controlled trials (RCTs) published before 2020, 75% of the programs were delivered at home or in a combination of other settings (e.g., community settings, health clinics).

According to previous studies, the impact of interventions relies on program characteristics (e.g., duration, intensity, tools, provider) as well as on sample characteristics (e.g., multiple risks, children’s and mothers’ age), and these aspects interact, modeling the effect size of the interventions (Bakermans-Kranenburg et al., 2003; Britto et al., 2015; Bower et al., 2020). However, Jeong et al. (2021) did not find evidence that child age, intervention duration, delivery, setting, or risk of bias in the studies modified the effect of the interventions but noted that the context in which the programs were implemented and their content did. The authors showed that programs implemented in low- and middle-income countries (LMICs) have greater effects than those implemented in high-income countries. Additionally, programs focused on responsive caregiving were nearly four times more effective in improving parenting outcomes than those that used other approaches, such as programs that provided information on child development, parental stimulation, and/or learning materials (Jeong et al., 2021).

Historically, home visiting programs were thought to be a universal approach across many health-focused services (Dufee et al., 2017; Finello et al., 2016) and nowadays, are one of the main strategies to support families and children at risk, such as low-income families and adolescent parents, or with additional needs (World Health Organization & UNICEF, 2022). In this sense, many programs, despite being designed to be universal, address mothers or children with clinical conditions, such as maternal depression, autism spectrum disorders, or infants at biological risk for developmental disorders (Bornstein et al., 2022; Ferreira et al., 2020; Mountain et al., 2017; Puthussery et al., 2018). Nevertheless, there is still a need to understand how well the home-visiting parenting programs work and fit the population without clinical conditions. Furthermore, most studies have focused on child development and behavior, and few have explored the crucial role of mother-child interaction in child development, as highlighted by Jeong et al. (2021) and Jeong et al. (2022).

Previous reviews (Bakermans-Kranenburg et al., 2003; Britto et al., 2017; Mountain et al., 2017; Shah et al., 2016) have demonstrated robust evidence of the positive effects of home-visiting parenting programs (HV-PPs) on early childhood development and parenting outcomes. Recently, a systematic review by Jeong et al. (2021) analyzed 102 unique RCTs designed to assess the effectiveness of parenting interventions on early child development and parenting outcomes. This review included studies published up to November 2020 and found that 69% used responsive caregiving components to improve parent-child interactions (n = 70). However, only 24 studies specifically analyzed the impact of home visiting programs on parent-child interactions, and most of them (n = 19) were published before 2018 (Jeong et al., 2021). Considering previous reviews were very heterogeneous regarding the intervention design and parenting outcomes, there is a need to focus exclusively on HV-PPs addressing the mother-child interaction outcomes in early childhood. Furthermore, most studies analyzed in previous reviews were published before the Nurturing Care Framework was announced in 2018 (Britto et al., 2017; World Health Organization et al., 2018). This framework is a benchmark for studying responsive caregiving in early childhood. Therefore, there is still a need to examine the evidence on this topic after this timeframe.

The present study aimed to systematically review empirical studies published in the scientific literature that examined the effects of home-visiting parenting programs delivered to improve the quality of mother-child interactions in early childhood. The following questions guided this review: (i) What are the main characteristics of HV-PPs? (ii) What constructs and measures were used to assess the quality of mother-child interactions (main outcome)? (iii) What were the main effects of HV-PPs on mother-infant interactions? (iv) What was the methodological care of the studies reviewed?

The systematic review protocol was registered on the PROSPERO platform on 09/13/2019 (CRD42020151122). This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statements (Page et al., 2021). We performed a formal narrative synthesis based on the Synthesis Without Meta-analysis (SWiM) guidelines (Campbell et al., 2018).

The findings of the present review provided evidence that home-visiting preventive parenting programs improved mother-child interactions. In 76% of the studies reviewed, positive effects were observed despite the diversity in their study design, sample characteristics, measures, and constructs assessed. Even though four studies did not demonstrate effects on the main outcome, they demonstrated other benefits of home-visiting programs, such as improved mothers’ knowledge of caring for infants (Høifødt et al., 2020) and reduced parental stress (Firk et al., 2020). The present systematic review adds to the current literature with its in-depth exploration of preventive home-visiting programs specifically designed to improve mother-infant interactions, an essential component of nurturing care to promote child development.

First, it is important to highlight that the studies reviewed presented good methodological care, with more than 80% classified as strong and 18% classified as moderate in the overall rating of the EPHPP tool (Thomas et al., 2004). Notably, almost 90% of the studies analyzed were RCTs, which is the recommended study design for examining the efficacy of intervention programs. Then, the methodological aspects of these studies guarantee the reliability of their findings.

With regard to the “main characteristics” of HV-PPs, 13 different programs on mother-child interactions were analyzed. Most studies, except those by Chung et al. (2018) and Vargas-Porras et al. (2021), were based on other known programs in which positive effects have been previously demonstrated (e.g., Berlin et al., 2018; Conti et al., 2021; Harden et al., 2021; Hepworth et al., 2020). Most programs made adaptations to address a specific population (e.g., Firk et al., 2020), providers (e.g., Christodoulou et al., 2019), setting characteristics (e.g., Ammerman et al., 2022); others used mixed programs (e.g., Alarcão et al., 2021) or components of another program (e.g., Alvarenga et al., 2019; Alvarenga et al., 2021). In addition to home visits, some programs used additional strategies, such as sessions at postpartum nursing centers (Chung et al., 2018), hospital visits before mothers’ delivery (Høifødt et al., 2020), and phone calls (Vargas-Porras et al., 2021). Mixing strategies to deliver programs is an effective option as it enhances participants’ exposure to the program’s main messages (Britto et al., 2015). In general, adaptations and fidelity assessments were carefully described, as recommended by Bakermans-Kranenburg et al. (2003) and Mountain et al. (2017), ensuring methodological consistency in program implementation. Moreover, cultural adaptations were also described, mainly for studies conducted in middle-income countries (e.g., Barone et al., 2020), ensuring the program’s core components but also allowing some flexibility to the local culture and population, as recommended by Lansford et al. (2022).

The heterogeneity of the programs in terms of the number of sessions (dosage), intensity, and start time was noteworthy. The mean number of sessions was 19, ranging from three to 62, delivered according to various schedules. A mixed schedule, starting weekly with a subsequent monthly schedule, has been used for the longest programs (Alarcão et al., 2021; Conti et al., 2021; Tomlinson et al., 2020). The three studies that presented the lowest number of sessions (three to five sessions) did not report positive effects of the programs compared to the control group (Chung et al., 2018; Høifødt et al., 2020; Kristensen et al., 2020). Regarding the reviewed studies, the minimum dosage of the programs that verified effects on mother-child interactions was six sessions (Barone et al., 2020). In 76% of the studies reviewed, the effects of home-visiting programs on mother-child interactions were independent of the dosage and intensity schedule. Despite the vast literature on this topic, the best dosage and intensity of parenting programs remain unknown (Bakermans-Kranenburg et al., 2003; Britto et al., 2015; Morrison et al., 2014; Mountain et al., 2017). In this sense, our findings are consistent with those of Jeong et al. (2021) and Britto et al. (2017), who showed that the program’s effectiveness was not modified by intervention duration, delivery, or setting. However, our review indicated that fewer than six sessions were insufficient to promote positive effects in interactions between mothers and children. Nevertheless, implementing home-visiting programs may have significant economic implications; thus, it would be relevant to establish the optimal number of home visits necessary to achieve the best effects on parenting and child development outcomes (Tazza et al., 2023).

In studies examined in the current review, most programs started their activities when the children were six months old or younger, and few offered sessions from the gestational period through the months following childbirth. Notably, from 15 programs that started their activities from pregnancy up to the third postpartum month, only four studies did not report a positive impact on mother-child interactions when intervention and control groups were compared (Chung et al., 2018; Firk et al., 2020; Høifødt et al., 2020; Kristensen et al., 2020). Although the meta-analysis by Bakermans-Kranenburg et al. (2003) reported that interventions starting when children were older than six months of age achieved better results than those starting prenatally or before six months of the children’s age, these findings were not confirmed by Jeong et al.’s (2021) meta-analysis. Interestingly, Britto et al. (2015) highlighted that the duration of programs may be more relevant than dosage and intensity depending on the intended outcomes. For instance, programs aimed at enhancing parenting knowledge could be shorter than those aimed at impacting children’s outcomes, such as cognitive development (Britto et al., 2015). Thus, the combination of short duration, very early start, and a small number of sessions could explain the absence of effects compared to the control group observed in the present review of the NBO (Høifødt et al., 2020; Kristensen et al., 2020) and “Tips on Caring for Your Baby” (Chung et al., 2018) programs on mother-child interactions.

Provider profiles have technical and economic implications. In the present review, most programs (88%) were delivered by trained health and education professionals. Unlike previous reviews (Bakermans-Kranenburg et al., 2003; Britto et al., 2015; Jeong et al., 2018), only two programs, both from South Africa, have been delivered by laypersons (Christodoulou et al., 2019; Tomlinson et al., 2020). The authors showed that the program delivered by trained community workers and mentor mothers improved maternal responsiveness and sensitivity compared to the usual care group, encouraging this sustainable service in low-resource settings. Programs delivered by nonprofessionals seem to be more cost-effective and culturally adapted (Munns et al., 2016) and are as effective as those delivered by professionals (Bakermans-Kranenburg et al., 2003; Britto et al., 2015; Jeong et al., 2018; Mountain et al., 2017). However, as pointed out by Peacock et al. (2013), although home-visiting programs delivered by trained nonprofessionals improved child development and health outcomes, they frequently did not significantly impact high-risk children from disadvantaged families with complex problems. Then, assuring adequate training and support for paraprofessionals (Munns et al., 2016; Peacock et al., 2013; Vu et al., 2015), beyond addressing issues concerning program design and implementation processes, would help improve the quality and effectiveness of parenting programs (Aboud & Prado, 2018; Lansford et al., 2022).

Our findings showed that video support was the main strategy used to deliver the interventions, mostly as video feedback during home visits but also as non-in-person strategies, such as video-assisted programs and vignettes (Ammerman et al., 2022; Chung et al., 2018; Vargas-Porras et al., 2021). Programs also used live feedback (e.g., Alarcão et al., 2021; Conti et al., 2021) and counseling strategies (Christodoulou et al., 2019; Tomlinson et al., 2020). Video feedback is a common strategy that is used for various purposes. Specifically, it is extremely useful to improve parent-child relationships as it provides opportunities for parents to reflect on their own behaviors and register their progress along with the intervention (Balldin et al., 2018; Juffer et al., 2017). Nevertheless, video feedback interventions are frequently time-consuming and more expensive than other strategies, which may limit their scalability with fidelity in real-world community settings (Balldin et al., 2018). Interestingly, in the current review, most programs using video feedback were developed in high-income countries (e.g., the USA and Germany) and included smaller sample sizes (mean = 124 participants). In contrast, other strategies were used in more diverse cultural contexts (e.g., South Africa, China, and Colombia) with larger samples (mean = 536 participants), suggesting constraints on using video feedback in low-resource settings. However, with technological advances, the development of apps may facilitate the implementation of large-scale video-supported programs (Vale et al., 2022).

The studies analyzed in the current systematic review included diverse tools and measures to assess many aspects of mother-child interaction. We observed that mother-child interactions are typically evaluated using observational methods. Conversely, Brito et al.’s (2015) systematic review of studies developed exclusively in LMICs reported the extensive use of self-report tools to assess the impact of programs on parenting outcomes. Most studies in the present review were conducted in high-income countries; thus, these differences may be related to the settings in which the studies were conducted. Nevertheless, a prior review of group-based parenting programs demonstrated that studies using observational and self-reported measures showed consistent results, indicating the effectiveness of both methods in assessing changes in parenting practices following the programs (Branco et al., 2022). Of note, among the four studies that did not show significant effects of the intervention, two used observational and validated scales (NCATS and EAS) and assessed mothers’ and children’s behaviors and dyadic interactions (Chung et al., 2018; Firk et al., 2020). The other two studies used self-report scales (MPAS and MABISC) and assessed only maternal behaviors (Høifødt et al., 2020; Kristensen et al., 2020).

In the present review, eight different tools were used in 14 studies based on observational measures. Observational measures are considered the “gold standard” when assessing parent-child interactions in particular, as they can capture positive and negative details of the early dyadic relationship in real-time, in naturalistic or experimental scenarios, using structured- or free-play tasks (Gridley et al., 2019; Nascimento et al., 2023; Roggman et al., 2013). However, recent systematic reviews (Gridley et al., 2019; Jeong et al., 2022) showed that the psychometric properties of these tools have not been sufficiently explored, which may compromise their use for research and clinical purposes. Most studies analyzed in the current review reported inter-rater reliability; however, cultural adaptations and other psychometric measures, such as validity assessments, were poorly described, which is in agreement with previous reviews (Gridley et al., 2019; Jeong et al., 2022). Of note, a few tools have been created by the authors themselves and tested in previous studies, but their measurement properties have not been reported (e.g., Christodoulou et al., 2019; Tomlinson et al., 2020). Despite the increasing interest in promoting responsive caregiving in the last few decades, Jeong et al. (2022) highlighted the need for more research and guidance regarding valid and reliable measures of parent-child interactions and responsive caregiving.

Maternal behaviors, such as sensitivity, responsiveness, warmth, and intrusiveness, were the main constructs assessed in the 14 studies in the current review. Child behaviors were assessed separately in six studies, and the mother-child dyadic interaction assessment was used in seven studies. Only four studies used a holistic approach to explore mothers’ and children’s behaviors and dyadic interactions (Alarcão et al., 2021; Christodoulou et al., 2019; Chung et al., 2018; Firk et al., 2020). The constructs were highly determined by the tools used in the studies, but we noted some concept overlap, making it difficult to quantify which aspects of the mother-child interactions were more commonly assessed and impacted by the programs. For instance, the Parental Stress Index, a tool frequently used to assess parent-child interaction, has three subscales, but only parent-child dysfunctional interaction directly measures dyadic relationships. Furthermore, this subscale is focused on stressful situations involving parental caregiving; thus, it may not capture “healthy” interactions satisfactorily. This issue was also highlighted in a prior systematic review by Jeong et al. (2022), which revealed that among 47 studies examining responsive caregiving, only one used a tool developed specifically to measure responsiveness; the other studies assessed correlated and broader aspects of the parent-child interaction.

We observed a predominance of interest in positive maternal behaviors, such as sensitivity, responsiveness, and warmth, during interactions with their children, compared with negative behaviors, such as intrusiveness and hostility. Only five studies have measured negative maternal behaviors (Ammerman et al., 2022; Berlin et al., 2018; Conti et al., 2021; Hepworth et al., 2020; Tomlinson et al., 2020). Certainly, the main objective of all parenting programs is to improve positive behaviors; however, this does not ensure a decrease in negative behaviors (Roggman et al., 2013). Thus, balancing these complementary aspects of mother-child relationships would help us better understand the effects of parenting programs.

Another unexpected finding from our review was the small number of studies (12%) that assessed mothers’ and children’s behaviors as well as dyadic interactions, such as synchrony, contingency, and mutuality, using observational tools (Alarcão et al., 2021; Chung et al., 2018; Christodoulou et al., 2019; Firk et al., 2020). Mother-child interactions are complex and multifaceted relationships that require a broad and holistic approach (Knerr et al., 2013; Leclère et al., 2014). Children are active elements of the mother-child relationship, so their behaviors, temperaments, and preferences may modulate their interactions, as well as the characteristics of their mothers do. Thus, assessing mothers’ and children’s behaviors separately is insufficient to understand the quality of their interactions (Knerr et al., 2013; Leclère et al., 2014).

Since most programs improve positive behaviors (e.g., sensitivity, responsiveness, and contingency) and reduce negative behaviors (e.g., intrusiveness and hostility) during mother-child interactions, attention should be paid to interventions without expected effects. Chung et al. (2018) observed an increase in the quality of mother-infant interactions within the intervention group, but the differences between the groups were not significant. Despite the methodological strengths, the authors argue that cultural aspects, for example, the “Do the months” ritual, staying at nursing care centers after childbirth, and modesty and humility values in Taiwanese society, might have compromised the program’s results (Chung et al., 2018). Furthermore, the Taiwanese was based on the American evidenced-based program “Keys to Caregiving” program (Spietz et al., 1990), with the materials (CD and manuals) translated into Chinese; however, a cultural adaptation was not described, possibly affecting the implementation process (Lansford et al., 2022). In addition to cultural issues, delivery strategies based on educational materials may explain this study’s results. According to Jeong et al.’s (2021) meta-analysis, programs that did not include responsive caregiving components in their delivery strategies were less effective than those based on these contents.

Surprisingly, two other studies (Høifødt et al., 2020; Kristensen et al., 2020) using Brazelton’s concepts and framework (Brazelton et al., 1974; Nugent et al., 2007) did not attain the expected positive effects of their programs on mother-child interactions. Moreover, these three programs share some program design characteristics, such as low dosage, low intensity, and a very early start time, suggesting that these strategies could not improve the mother-child interactions as expected. Differing from the study by Chung et al. (2018), Høifødt et al. (2020), and Kristensen et al. (2020) examined programs based on the NBO, another American program with promising positive effects on mother-child relationships, inclusive in previous studies in Nordish cultures (Yago et al., 2023). Nevertheless, another review did not find a consistent impact of home-visiting programs based on Brazelton’s approach on the sensitivity and emotionality of the mother-infant relationship, although positive effects on other parenting outcomes, such as knowledge, have been reported (Tazza et al., 2023). The assumption that increased parental knowledge would be associated with increased parental sensitivity and confidence in their caregiving skills was not confirmed by Høifødt et al. (2020) and Kristensen et al. (2020). According to Tazza et al. (2023), the heterogeneity of the samples in terms of exposure to risk factors and vulnerability explains the inconsistency of findings across studies, with programs involving clinical conditions performing better than universal preventive interventions. Notably, the samples included in studies by Høifødt et al. (2020) and Kristensen et al. (2020) constituted predominantly well-functioning families, and the “ceiling effect” on questionnaires used to assess mother-child bonding and maternal confidence may explain the absence of significant differences between groups.

Firk et al. (2020) highlighted the need to customize programs according to sample characteristics because of the differential effects of interventions across populations. Their study included a small sample of German adolescent mothers and used an adaptation of a well-known program (STEEP^TM); (Erickson & Egeland, 2004). Nevertheless, despite participants’ satisfaction with the program (Firk et al., 2020) and the positive impact of the German version of the program on a high-risk sample (Suess et al., 2016), no effects on mother-child interactions were observed. Although the STEEP program has been proven effective, Firk et al. (2020) argued that longer and more intense programs may be necessary to achieve goals for specific groups, such as adolescent mothers. They also pointed out that problematic interaction patterns could emerge very soon in high-risk groups; therefore, interventions starting after the third month of a child’s age could be too late. These findings highlight the need to understand “what works for whom” and are supported by the differential susceptibility theory of parents in the context of preventive programs (Chhangur & Belsky, 2023). Moreover, this shows that an ideal program design is far from being defined.

In conclusion, the present review confirms the effectiveness of different home-visiting preventive parenting programs on mother-child interactions in early childhood. However, the findings do not allow us to recognize a pattern of program design that is more effective than others; further, it seems that the combination of fewer than six sessions, a duration shorter than three months, and a very early start time did not positively impact the mother-child interactions, as expected. Notably, most interventions with significant outcomes used a video feedback approach and were assessed using observational methods.

Despite these distinct results, our findings revealed that there is still a predominant interest in positive maternal behaviors, both in the program content and the outcomes measured. Gaps remain in our understanding of the effectiveness of programs in reducing negative maternal behaviors such as intrusiveness. Few studies have used a comprehensive approach to mother-child interactions, including child behaviors and assessing aspects of dyadic relationships, such as synchrony and contingency. These findings indicate the need to widen the gaze at the parent-child relationships to capture the real impact of home-visiting programs on families’ lives.

We noted significant heterogeneity in the program design, analyzed constructs, and tools used to measure their effects. The most evident concern is how authors use and interpret measures and define constructs, sometimes causing discrepant findings between studies that use the same tool. These distortions obscure the understanding of the results since the mother-child interaction is marked by overlapping constructs.

We have provided a careful and updated synthesis of studies analyzing the effectiveness of home-visiting preventive programs on mother-child interaction, following recognized protocols. Notably, none of the reviewed studies included clinical samples (e.g., participants with maternal depression and child behavioral disorders), reinforcing the preventive focus of the programs and making the results more generalizable.

Nevertheless, the present review has some limitations. We did not perform a two-author independent screening of the papers, although the other authors double-checked the entire review process. Furthermore, the authors have extensive expertise in the topic and producing systematic reviews, which has contributed to improving the accuracy of the current review. We included only studies assessing interactions between mothers and their children under two years old, preventing us from analyzing the long-term effects of the interventions. Further, we did not evaluate programs involving other caregivers, such as fathers, which would have provided a broader picture of the environment in which early interactions occur.

This review has several practical implications. Most of the studies were classified as having strong methodological quality, but it was not yet possible to establish the “ideal” format for home-visiting preventive parenting programs due to the huge heterogeneity of intervention models. However, our findings suggest that more individualized strategies, such as video feedback and live feedback, could have benefits since they strengthen maternal self-awareness and provide space for mothers to reflect on their own parenting behavior. The choice of the best strategy relies on the objectives and resources of each program as well as the context in which the intervention will be implemented. The “unsuccessful” studies also brought reflections that should be considered when designing interventions to improve mother-child interactions from a preventive perspective. First, the cultural adaptation of programs and measurement tools should be strongly considered, not only for LMICs but also across different cultures. Second, the characteristics and functioning of the addressed population may require special program adjustments, such as the number of sessions, program intensity, and starting point. Third, the core messages and materials of the program and how to deliver them should be carefully considered by choosing content and approaches that best fit the cultural and sociodemographic characteristics of families eligible for the programs, as well as their previous parental knowledge, skills, and experiences in responsive caregiving and child development. At least, more studies on the sustainability of these programs and how to implement them feasibly in different contexts, especially in LMICs, are required.