An implementation strategy bundle to improve home visit quality of the national child development program in Brazil: an implementation feasibility trial

Abstract

Background

Programa Criança Feliz (PCF) is Brazil’s home visitation program aimed at enhancing early childhood development. Evaluations of the program have found significant program challenges and implementation barriers, including the lack of a structured curriculum, insufficient training, and little supervisory support. This study tests the revised content of the home visits and new implementation strategies aimed at addressing these barriers and enhancing the quality of PCF home visits.

Methods

The implementation strategies were piloted across 8 diverse municipalities in an implementation feasibility trial. The strategy bundle included a 40-hour initial training for home visitors using demonstration and simulation-based methods (based on the Reach Up methodology), an 8-hour supervision-focused training module for supervisors, and standardized home visit guidelines and an activities compendium. The new strategies were assessed using a one group pre-post analysis along with mixed methods to assess the extent to which they were acceptable, feasible, and associated with a change in home visit quality. A paired t-test and an independent t-test analysis were used to assess the change in home visit quality. The implementation outcomes were assessed with qualitative analysis and the Framework Method approach.

Results

The proposed home visitation guidelines, material, training, and supervision process were determined to be highly acceptable, feasible, and associated with improved quality of home visits. The home visit quality scores significantly increased by 14.68 points (SD = 14.89, CI 95%: 7.27–22.08, p = 0.0006), according to the paired t-test. The study participants provide insightful suggestions for adaptations that can occur before testing the strategies more broadly. Key suggested adaptations included adjusting activity difficulty to individual developmental levels rather than age alone, shortening training duration to improve staff access, and incorporating guidance for culturally diverse and traditional communities.

Conclusion

The findings suggest three transferable design principles for home visitation and paraprofessional-delivered public health programs: reducing excessive discretion through structured, age-appropriate visit guidance; externalizing quality through experiential training methods such as demonstration and role-play; and embedding feedback loops through structured supervision and monitoring. These principles may generalize to programs facing heterogeneous staff preparation, high turnover, and limited supervisory capacity.

Supplementary information

The online version contains supplementary material available at https://doi.org/10.1186/s43058-026-00994-z.

Contributions to the literature

• Developing an adaptable curriculum that allows home visits tailoring to each family’s context and characteristics can help minimize cultural and contextual barriers. • Implementing a 40-hour training and supervision process enhances fidelity and the quality of home visits and is more feasible for large-scale implementation than longer training periods. • Using household objects and daily routines instead of a toy kit can facilitate large-scale implementation.

Background

The first five years of a child’s life are characterized by rapid growth and adaptation, with the brain being highly plastic and capable of enhancing specific capacities and abilities [1–3]. Interventions that support early childhood development (ECD) in children have been shown to have long-term benefits including higher adult wages [4, 5], better educational attainment [6], improved health biomarkers [7], reductions in violence [8], and physical growth in the subsequent generations [9]. Teaching caregivers how to effectively care for and stimulate the development of their children is an important strategy to improve early childhood development outcomes [10, 11]. Programs that conduct home visits to improve caregiver knowledge and parenting practices have shown success at improving child development [10, 12–17].

Although using home visits to improve child development shows great promise, they often fail to produce the expected outcomes when scaled. The reach, quality, and equity of the programs are often inadequate for underserved-populations [18–25]. Large-scale programs need close monitoring and continuous improvement of the implementation process to strengthen the quality of the program [26, 27]. Efforts to improve the quality of home visitation programs have led to large benefits in terms of quality and impact [28–30]. Following the principles described in the MERLA cycle (monitoring, evaluation, research, learning, and adaptation cycle), after monitoring the program for barriers to program implementation, the implementation process should be adapted to address the barriers [31, 32]. Once the adaptations have been identified, they should be tested in the field to ensure they are feasible and show promise of being effective [33–35].

Programa Criança Feliz (PCF) of Brazil is the largest home visitation program to support child development in the world [36]. The program aims to improve ECD in the country’s most vulnerable populations [37]. It trains and supports paraprofessionals to conduct home visits with caregivers of children under 3 years (or under 6 years if the child has a disability) from vulnerable communities. The home visitors (HVs) are expected to support the caregivers, promote ECD and guide families on how to access other government social services. Recent evaluations of PCF have identified multiple barriers to effective implementation, including a lack of standardized home visit guidelines and materials, insufficient training for home visitors, and inadequate supervisory support [37–41].

Prior to the implementation strategies introduced by this study, training for HVs was organized in a cascade model. Federal level staff provided training for State level staff, who trained municipality facilitators (most of the time, the supervisors). The training protocol included an initial 40 hours of theoretical training and another 40 hours of training from a UNICEF home visitation model (Care for Child Development). However, the State level staff did not provide face-to-face training on a regular basis, so many municipalities never received face-to-face training. No refreshment training was included in the protocol, nor did it include specific training for the supervisors. Training content, duration, and frequency varied, and was inconsistently delivered. Although the national PCF protocol recommends periodic training using official materials, implementation of these recommendations differed across municipalities, resulting in uneven preparation of HVs and supervisors.

A primary barrier that was highlighted was the quality and usability of broad guidelines for home visits. Home visitors expressed a lack of standardized protocols and material for home visits [38]. Challenges are exacerbated by weaknesses in the training process and supervision the HVs receive.

There is a need for research to be conducted on PCF to improve its overall effectiveness. The objective of the current study is to test the acceptability and feasibility of a new implementation strategy bundle and to test the influence they have on the quality of home visits by PCF. The study will help to determine if the new implementation strategies created observable changes in the quality of home visits and to identify how the strategies can be adapted to further improve fit with local context.

Methods

The implementation strategies

For this study, a new implementation strategy bundle was developed to address previously identified barriers related to home visit quality. One key barrier highlighted in previous studies was a need to improve the guidance and material for HVs [37, 38, 42, 43]. Another barrier was the lack of supervision and feedback received by supervisors to ensure the quality of home visits [38]. To address these barriers, a research team at the Medical School of the Universidade de São Paulo and the Reach Up programme from, The University of the West Indies, Jamaica with years of collective learning about the program and with the support of the Lego Foundation, developed an adaptable approach to enhance the quality of home visits through more age-appropriate and culturally suitable guidelines and material. The approach is based on the Reach Up Early Childhood Parenting Program and curriculum [44], adapted to provide more choice for HV’s in activities used and reduced quantity of toys and materials needed for the visits and is more conducive to large-scale implementation in diverse contexts [45]. The revised curriculum includes a set of age-appropriate activities (the providing a consistent basis for interpreting post-test activities compendium) from which activities are selected, home visit guidelines, a supervisory protocol, and monitoring forms. The team also adapted the Reach Up training protocols to teach the HVs how to effectively conduct home visits with the new content. The training session included 40 hours of in-person or online training for the HVs. The supervisors and managers in the participating municipalities received the same training, plus an additional 8-hour training module on supervision and monitoring. Training was conducted by trained members of the research team with previous training in the Reach Up programme. Table 1 provides an overview of the implementation of PCF before and after the new implementation strategy bundle to highlight differences.

Table 1.

Implementation of PCF before and after the new implementation strategy bundle

Dimension	Before the new bundle	After the new bundle
Training – overall structure	Fragmented training pathway composed of 80 hours mandatory course (Basic Course, Home Visit Guide, and CDC), mostly theoretical and implemented with variability across municipalities.	Integrated and standardized curriculum with an initial 40-hour synchronous training, focused on practical skills for conducting home visits and using active learning methods.
Training – pedagogical focus	Emphasis on normative and conceptual content, with limited practical guidance on how to conduct visits.	Emphasis on practical delivery of home visits, structured planning, and age-appropriate selection of activities based on family needs.
Training – support materials	No official set of activities, but only few examples. The visitors had to propose activities by themselves, frequently using internet suggestions.	Structured compendium of activities organized by age and developmental domains, distributed in a printed version.
Supervision – structure	No structured supervision process and no specific training for supervisors.	Formal supervision structure supported by a Supervisor Manual and a dedicated 8-hour training module, with clearly defined roles and routines.
Supervision – focus	Mainly administrative supervision focused on paperwork.	Supervision focused on quality of implementation, pedagogical support for home visitors, and systematic monitoring of activities.
Visit strategy – planning	Heterogeneous and poorly standardized planning across home visitors.	Structured planning supported by the visit guide, with activities aligned to gestational stage or child age.
Visit strategy – content	Limited number of officially available activities and no detailed guide on visit steps.	Detailed guide describing visit steps and an expanded compendium of activities (>500 activities), with two suggested activities per visit.
Visit frequency	Standardized weekly home visits, regardless of case complexity or operational capacity, which created challenges for consistent implementation.	Biweekly home visits, with reorganization of content to preserve visit quality and support more consistent implementation.
Equity and cultural adaptation	No systematic guidance for traditional communities or children with developmental delays.	Structured guidance to support cultural adaptation and inclusion of children with developmental delays.

More details of the home visit curriculum, training methodology, and supervisory protocol are described in Appendix 1. The current study assessed the use of the adapted program curriculum in PCF.

Study location and participants

The municipalities that participated in the study were selected by the research team in collaboration with a committee of representatives from PCF to represent the diversity of the program beneficiaries. The municipalities were selected in the 4 regions of the country where PCF is primarily implemented – The north, northeast, southeast, and central-west – and included rural and urban communities, indigenous, quilombola (African-Brazilian), and riverside populations.

The strategy bundle was implemented and tested in two stages. The first stage was conducted to test the implementation outcomes of acceptability and feasibility, while collecting information on suggested adaptations of the strategy bundle. Stage one included the municipalities (Municipality, State): 1. Água Branca, Alagoas, 2. Tocantinia, Tocantins, 3. Ilha Comprida, São Paulo, and 4. Una, Bahia. Training for this group took place from July-August of 2022. A total of 28 HVs, 4 supervisors, and 2 managers received training in the use of the strategies and then used the new methodology for 2 months before evaluation. Semi-structured key informant interviews (KIIs) were conducted with 7 caregivers and 4 supervisors, and 8 focus group discussions (FGDs) were conducted with 32 staff members (28 HVs and 4 supervisors). Two FGDs were conducted in each municipality, one FGD to discuss the training and HV methodology and the other FGD to discuss the list of activities for the HVs (activities compendium).

The second stage was conducted to test the influence the implementation strategies had on the quality of home visits. Stage two included the municipalities (Municipality, State): 1. Oriximiná, Pará 2. Jordão, Acre 3. Petrópolis, Rio de Janeiro and 4. Camaçari, Bahia. Training for this second group comprising 53 HVs, took place in August – September of 2022. Before the training began, independent assessors observed and scored the quality of the home visits. The quality of home visits was assessed again after 3 months of implementation by the same assessors. There were 18 HVs that were present for both the pre-test and post-test. The other 35 HVs were present for only the pre-test or post-test, due to high staff turnover. Of the 35 HVs present at only one timepoint, 11 HVs present only at pre-test were observed before training was delivered. Those HVs subsequently left the program prior to the post-test assessment due to turnover. The 24 present only at post-test were new hires who joined the Program after the pre-test observation period. They received the full training before implementation and the post-test assessment, meaning that all HVs observed at post-test, whether in the paired or independent sample, had been trained prior to their assessment, providing a consistent basis for interpreting post-test scores as reflecting trained performance.

Study design

The current study is an implementation feasibility trial to test the implementation strategy bundle. An implementation feasibility trial is an effective method to test the influence of new implementation strategies on implementation and service outcomes [33, 34, 46–48]. The primary outcome of the study is the quality of home visits by the HVs of PCF, which reflects the effectiveness of the implementation strategies to improve HV performance [49]. Improved quality of home visits is expected to lead to improvements in caregiver knowledge and ultimately child development outcomes, following extended exposure [29, 50, 51]. The secondary outcomes are the acceptability and feasibility of the new strategy and recommendations for adaptations, measured and analyzed with qualitative methods.

The study trial uses a pre-post test study design to assess the influence of the bundle on home visit quality [34, 52]. The study includes one group, comprising those who received the new bundle. All HVs in the participating communities participated in the training. Since the trial was implemented the group of beneficiaries enrolled in the Criança Feliz program, no exclusion criteria were considered.

Sample size calculation

The sample size calculation for the quantitative assessment is based on a previous study that used the same home visit quality scale, and reported a mean baseline HV score of 59 points with a standard deviation of 11 [53]. The improved home visiting content and training were hypothesized to improve home visit quality scores by 1 SD. Additional parameters are set at 0.05 for the alpha error (two-tailed), and study power of 0.08. The sample size calculation indicated a desired sample size of 16 HVs. The study anticipated a loss of follow-up of 30%, therefore the minimal sample size was set at 25 HVs. The sample size is deemed adequate based on standards of implementation feasibility pilots described in the literature and used by similar studies [33–35, 52, 54, 55].

The sample size for the qualitative assessment was determined based on an estimated point of thematic saturation and data adequacy [56]. Based on previous qualitative studies of home visit material, it was projected that two FGDs per municipality would provide data adequacy [29, 57]. The FGDs were complemented by individual KIIs in each municipality.

Home visit quality instrument

To evaluate the quality of home visits by the HVs, independent researchers were trained to use the Home Visit Quality Check list (The Check List). The Checklist was a modified version of the Reach Up Observation checklist, updated based on lessons learned from the field and a consultation exercise with a team of experts [53]. The Reach Up Observation Checklist was developed to be a simple and easily administered tool for program supervisors to monitor quality of home visits and support home visitors. It was developed to be simpler, yet comparably effective to the Home Visit Rating Scales (HOVRS-3), the gold standard in the field [53, 58]. The Reach Up Observation Checklist has high internal consistency (α = 0.81–0.86) and high concurrent validity with the HOVRS. The adapted version of the checklist used for this study contains 22 items divided into five sections: Review of the Last Visit, Activities and Methodologies, Caregiver Relationship, Child Relationship, General Vision of Visit. Items were scored on a four-point ordinal scale (0–3), with response categories representing graded levels of quality and completion. Data collection occurred in July 2021, two weeks before the staff training (July and August 2021) after 3 months of the new methodology implementation (November and December 2021). For both timepoints, data was collected simultaneously in the municipalities.

Implementation outcomes instrument

The interview guide to assess the implementation outcomes included questions regarding the acceptability of the new program content, the feasibility of implementing/using the new protocols, and what suggestions participants have for adaptations. The interview guide was used for the FGDs and KIIs. The interview guide included 9 open-ended questions related to the home visit content, training, and supervisory protocol. Questions were included to probe information regarding the acceptability, feasibility, and adaptations of each component of the implementation strategy bundle. The interview guide was developed by the research team, utilizing the concepts of implementation outcomes described by Proctor, et al., 2011 [49]. The interview guide was piloted with a small group of HVs to identify opportunities to clarify the questions.

Research ethics and consent to participate

The current study received ethical approval from the PI’s Institution, under protocol number CAAE 51767121.10000.0068. All participants provided written informed consent following a complete description of the study, before participating in the study. All transcripts and interview results were without any identifiable information.

All participants received an explanation of the study’s purpose and interview procedures. If the participant agreed to participate in the study by giving written consent, then they began the interview.

Data analysis and interpretation - home visit quality

The home visit quality scores were assessed in two ways: 1) a descriptive analysis of scores before and after implementation, and 2) a t-test analysis to compare pre- and post-scores to determine if a change in home visit quality occurred following the use of the new implementation strategies. The descriptive analysis of pre- and post-implementation scores helped to determine the strengths and weaknesses of the home visits with or without the new content and the variance of quality scores were used to determine how the scores compared before and after the introduction of new implementation strategies. The descriptive analysis provided mean scores, standard deviation, and differences. The paired t-test was conducted with the sample of HVs that were scored in both the pre-test and post-test. The independent t-test was conducted with the sample of HVs that were present only for the pre- or post-test. Both the paired and independent t-tests were two-tailed with an alpha level of 0.05.

Checklist ratings were completed by a single observer for each observed home visit; visits were not independently double-rated by multiple observers. As a result, interrater correlation metrics could not be estimated from the study data. To assess whether any observer tended to score systematically higher or lower, we examined observer-specific scoring patterns relative to mean scores within the same municipality and timepoint (pre/post) strata; we did not observe evidence of consistent observer leniency or severity after accounting for site and timepoint differences.

Data analysis and interpretation – acceptability, feasibility, and adaptations

The implementation outcomes were assessed with qualitative analysis methods and the Framework Method approach, including a deductive and thematic content analysis approach [59, 60]. The approach is used to draw descriptive and explanatory conclusions clustered around themes. It includes the creation of a matrix output to summarize data, providing a structure for the researchers to systematically synthesize the data by case and by code [61].

A codebook was created before the analysis began based on the research objectives and implementation outcomes being studied. Each implementation outcome was matched with a component of the implementation strategy bundle (see Table 2 below).

Table 2.

Codes used to summarize data in the qualitative analysis

Matrix Codebook
“Acceptability of home visit methodology” “Feasibility of home visit methodology” “Adaptations to home visit methodology”
“Acceptability of training module” “Feasibility of training modules” “Adaptations to training modules”
“Acceptability of supervisory protocol” “Feasibility of supervisory protocol” “Adaptations to supervisory protocol”

All interviews and focus groups were conducted in person by the PI and 4 other members of the research team with experience in qualitative research (AB, ALC, LB, CO and NP). The interviews and focus groups used an open-ended semi-structured questionnaire, created by the research team. Given that KIIs and FGDs were facilitated by members of the study team, we implemented procedures to reduce social desirability bias, including emphasizing confidentiality, clarifying that participation and responses would not affect employment or standing in the program, using neutral non-leading prompts, and explicitly inviting critical feedback (e.g., what did not work well and what should be improved).

The interviews were recorded and transcribed by four members of the research team. The transcriptions were coded by two members of the research team that are trained in qualitative analysis (CMW and AB). They independently coded the same two KII transcripts and two FGD and then came together to discuss the codes they applied. After consistency between the two coders was reached, one researcher coded the rest of the transcripts (AB). When this process was complete, the coded quotations were extracted from NVIVO [62] and organized in a results matrix in Excel. The quotes were categorized by implementation outcomes (acceptability, feasibility, and adaptation) and by strategy-type (home visitation content, training, and supervision) (see Box1). The results matrix was then reviewed by two members of the research team that are experts in home visitation programs and familiar with PCF and the local context (CMW and AB). The researchers collaboratively analyzed the matrix, synthesized the information, and highlighted the most important quotes to be presented in the study.

The implementation outcomes used were based on the categorization of outcomes by Proctor, et al., 2011 [49]. For the current study, acceptability is defined as the perception that the intervention is agreeable, palatable, or satisfactory [49]. Acceptability was assessed qualitatively only. No quantitative acceptability scale or predefined numeric acceptability threshold was used in this feasibility trial. Instead, acceptability was operationalized as participants’ perceived satisfaction with, and perceived agreeableness/palatability of, the strategy bundle components, consistent with the implementation outcomes framework (Proctor et al.) [49]. These perceptions were elicited through FGDs/KIIs and analyzed using the Framework Method with a deductive thematic approach. Feasibility is the extent to which the new strategies can be successfully used within the local setting [49, 63]. The analysis of feasibility reports on how the implementation strategies were used in the local setting, to determine if their use was feasible. Feasibility was assessed qualitatively (KIIs/FGDs) using Proctor et al.’s definition (i.e., the extent to which the strategy bundle could be successfully used within the local setting). Feasibility questions explicitly probed feasibility of each strategy-type (home visitation content, training, supervision), including the training dosage (40 hours for HVs; additional 8-hour supervision/monitoring module for supervisors/managers), scheduling/logistical constraints, and perceived challenges of delivering the training in other municipalities. Adaptation is a process of thoughtful and deliberate alteration to the design or delivery of an intervention, with the goal of improving its fit or effectiveness in a given context [64]. The analysis of adaptation reports on any suggestions for adaptations to the bundle or intervention that were provided by study participants.

Results

Quality of home visits

The quality of home visit scores for all HVs, at pre-test and post-test, along with results from the paired t-test and independent t-test analysis are shown in Table 3. Quality of home visit scores were collected from 53 home visitors, 18 of which are paired samples (at pre- and post-test) and 35 are independent samples (11 present at only pre-test and 24 present at only post-test). In the paired t-test analysis the scores improved by 14.68 (SD = 14.89, CI 95%: 7.27–22.08, p = 0.0006). To contextualize the magnitude of this change, the checklist has a total possible score range of 0 to 66. Pre-test scores in the paired sample averaged 43.77 (66.3% of the maximum possible score), rising to 58.45 at post-test (88.6% of maximum). The observed improvement of 14.68 points represents approximately 22% of the total scale range, a shift that moved the average home visitor from below the upper two-thirds of the scale to well within the upper quartile. This suggests the change reflects a meaningful improvement in overall visit quality rather than movement within a narrow band of the scale. In the independent t-test analysis the scores differed by 23.16, (SD = 13.65, CI 95%: 16.99–29.33). Of the five sub-domains from the scale, four showed significant improvements, including: review of the last visit, activities and methodologies, caregiver relationship, and child relationship (shown in Table 3). The changes in sub-domain scores from pre-test to post-test are shown in Fig. 1. The standard deviation was greater in the pre-test scores than the post-test scores, representing decreased variance following the implementation of the new implementation strategies, as shown in Fig. 2.

Table 3.

Home visit quality scores

	Pre-Test Average	Post-Test Average	Difference	T-test p-value
All home visitors	39.39 (N = 29, SD = 12.79)	57.99 (N = 42, SD = 6.49)	18.6	-
Paired t-test analysis	43.77 (N = 18, SD = 32.76)	58.45 (N = 18, SD = 5.28)	14.68	p = 0.0006
Independent T-test analysis	33.89 (N = 11, SD = 10.09)	57.05, (N = 24, SD = 7.43)	23.16	p = 0.0000
Sub-domains (paired t-test)
Review of the Last Visit	1.72	4.57	2.85	p = 0.0002*
Activities and Methodologies	8.92	13.71	4.79	p < 0.0000*
Caregiver Relationship	12.27	14.52	2.26	p = 0.0065*
Child Relationship	10.62	14.23	3.62	p = 0.0028*
General Vision of Visit	10	11.04	1.04	p = 0.2545

Fig. 1.

Home visit quality sub-domain scores, pre- and post-test

Fig. 2.

Home visit quality scores, with variance, pre-test – post-test

Implementation outcomes: home visitation content

The complete set of quotes that were extracted from the transcripts can be seen in the Appendix 2.

Acceptability of the new home visitation content (guidelines, material, activities compendium) was high for all study participants. The most frequently reported advantage of the new content was the ease of selecting activities to conduct during the home visit.

A home visitor said, “This method helped us because we used to have a lot of difficulty choosing the activity, which used to be more complicated because each different activity had to be specific. And today, with this method, it’s easier? It allows the user to have access to many activities, so it’s even quicker for us to make our plan and go for a visit”

Several study participants commented that the new content was highly acceptable because it provided clear guidelines and a standardized structured process to execute the home visits.

A home visitor said, “[The home visit guidelines] was very different because we brought something already structured. You know there was a beginning, middle, and end. So it was a very innovative experience, both for the family and for us.”

The feasibility of implementing the new home visitation content was primarily expressed by how it was used and if any problems arose. The study participants described the home visitation content as feasible to implement and highlighted how specific components of the curriculum were used. For example, the task of recapping activities from previous home visits.

A home visitor said, “Regarding the recap of previous activities, some families began sending me videos of how the child performed, of how they progressed. Engagement improved after we started recapping.”

Adaptations of the home visitation content were suggested by some study participants. However, most participants did not have suggestions for how it could be adapted. Study participants commented that the activities’ compendium could be improved, specifically on the ability to adjust activities to the child’s ability.

A home visitor said, “as for the activities, they are great, but there are some mothers who, when we arrive, they say that the activity is delayed, because the child already does those things.”

A supervisor pointed out that it would be helpful if the description of the activities included images. Another supervisor commented that the music singing suggestion of the home visits was not well received.

Implementation outcomes: training protocol

The acceptability of the training protocol was high, overall. The study participants expressed appreciation for the changes they experienced in training, in comparison to the previous training methodology. The interactive dynamic of the new training protocol was well accepted by the supervisors and home visitors. Several participants commented that the training provided an important opportunity to improve their knowledge of their work. The most frequently expressed sentiment regarding the training was that it helped the HVs understand the tasks and structure of the home visits.

A home visitor said, “[The training] helped us better understand each step of the home visit, the before, during, and after.”

The portion of the training that included demonstrations of home visits and simulations (role play) conducting home visits was described as acceptable and feasible.

A home visitor said, “we’ve been here for three years, right? And we never had training like this, demonstrative, with theater and everything, no, there wasn’t.”

Participants’ feasibility feedback reflected feasibility of delivering and implementing the full training protocol and home visit package within their municipal context (including training duration and logistics), and perceived considerations relevant to replication in other municipalities. There were no comments by the study participants that indicated that the training protocol, or any of its parts, were not feasible to implement. Some study participants pointed out that the length of the training could be reduced because it was difficult for interns to participate in the training.

A supervisor said, “There is the question of timing. Not everyone can stay all day because of completion of internship hours, and that complicated the participation a little.

Adaptations of the training protocol were suggested by some study participants. A study participant suggested that there was too much repetition in the training activities, suggesting this could be reduced. Another adaptation that was suggested was to include information about traditional communities in the training. Most study participants commented that no adaptations were needed to the training protocol.

Implementation outcomes: supervisory system

The new supervisory system that was implemented to improve quality assurance for home visits was deemed acceptable by the supervisors that participated in the study. Several noted that the new supervision protocol is important to provide quality service to families. Several also noted that the new supervisory system was helpful because of the new forms and procedures that were provided to conduct supervisory visits with the HVs. The new procedures enable monitoring of the home visits to ensure consistent quality.

A supervisor said, “the evaluation of activities by the supervisor, the actual supervisory part, the instruments, I believe are quite simple, and they help when observing home visits.”

Discussion

The current research shows that the new implementation strategies were well accepted and feasible to implement in the local context. The strategies were also associated with an improvement in the quality of home visits. Providing HVs with a curriculum that allowed selection from sets of age-appropriate activities, clear guidelines, as well as effective training and supervision, enhanced the programs’ ability to promote early childhood development in underserved populations. This feasibility trial suggests the bundle functions as an integrated set of tools and routines that changes how front-line work is designed, learned, and supported, rather than simply adding resources or intensity. Three transferable principles may generalize to other home visiting and paraprofessional-delivered public health programs. (1) Reduce excessive discretion: step-by-step visit guidance paired with a constrained set of age-appropriate activity options can lower planning burden and reduce delivery variability, allowing HVs to focus on caregiver coaching and interaction rather than improvisation. (2) Externalize quality: experiential training (demonstration and simulation/role-play) makes “what good looks like” observable and repeatable, helping paraprofessional workforces translate abstract guidance into real-time practice. (3) Embed feedback loops: routine recap of prior activities plus structured supervision and monitoring forms transforms implementation from a one-time rollout into continuous learning through observation, feedback, and reinforcement. These principles are particularly relevant to programs facing common real-world constraints such as heterogeneous staff preparation, high turnover, and limited supervisory bandwidth.

These design principles are consistent with implementation science perspectives that emphasize sustainment through routine reinforcement and ongoing adaptation. For example, the Dynamic Sustainability Framework highlights that intervention effectiveness depends on continuous fit and iterative adjustment within changing service systems, which in this bundle is operationalized through supervision and monitoring feedback loops [18, 65, 66]. The bundle also aligns with Normalization Process Theory mechanisms by strengthening coherence (clear, structured work), collective action (making high-quality delivery feasible in routine practice), and reflexive monitoring (structured appraisal and improvement through supervision), which may support routinization of high-quality home visiting [67].

We expect these principles to be most transferable to community-delivered programs characterized by broad initial guidance, variable training quality, and limited supervision capacity; transferability should be tested empirically in future trials across diverse delivery systems and workforce models.

Our study results align with existing literature that indicates that structured home visitation guidelines and ease of selecting age-appropriate activities for the home visits are key factors for enhancing program effectiveness. Effective programs provide structured, yet flexible curricula to meet the needs of the families [16, 68]. This was reflected by the improvements in the quality of home visits seen in this study after providing improved home visitation content. The suggestions for adaptations to the home visitation content provided important feedback on how the strategies can be further improved before implementing and testing more broadly. The suggestion to provide enough activities to consistently engage children across multiple visits and the possibility of adjusting these activities not only to their specific developmental levels, but also to the culture and context have been noted as essential to maximizing the impact of home visits [69].

The HV’s expressed that the improved training protocol helped them better understand how to deliver the home visits and gave them more confidence in doing so. Effective training has been shown to enhance the competence of HVs, which also enhances their self-efficacy and job satisfaction [16]. The training protocol can potentially be further improved by addressing the HVs suggestion of limiting the repetition of some training activities and the overall time of the training, while ensuring the quality of the training was maintained.

Effective supervision is an essential element of home visitation programs for ensuring quality and fidelity [70]. Standardized supervision helps maintain consistent program activities and quality, across diverse settings and over time [70]. The supervisory system introduced in this study was well received by program participants, citing their appreciation for standardized guidelines and instruments. Previous research has shown that the use of structured monitoring tools to assess fidelity in home visitation programs enhances the supervision process and can lead to better implementation outcomes [16, 71, 72].

Workforce turnover poses a persistent implementation challenge for home visitation programs at scale: when HVs leave and are replaced, program quality is at risk unless new staff can be trained efficiently and quality can be monitored continuously without dependence on infrequent, centrally delivered training events. In this study, only 18 of 53 HVs were observed at both pre- and post-assessment timepoints, illustrating the scale of turnover even within a short implementation window. Notably, all 24 HVs present only at post-test had been hired after the pre-test observation and received the full training before the post-test assessment, demonstrating that the training system was able to absorb new hires within the implementation period. To address the broader challenge of sustaining quality under ongoing turnover, the implementation model was designed as an integrated system with four mutually reinforcing components. First, training duration was reduced from 80 to 40 hours, directly lowering the operational burden of retraining replacement staff without sacrificing the core competencies needed for quality home visiting. Second, delivery was decentralized: municipalities received the complete standardized training package—including slides, manuals, and facilitation guidance—and State and Municipal coordinators were designated as responsible for delivering the onboarding module to newly hired HVs, removing dependence on the research team for ongoing training delivery. Third, a structured 40-hour onboarding module for new HVs and an 8-hour supervision-focused module for supervisors were embedded in the model, ensuring that new staff enter with a consistent preparation regardless of when they are hired. Fourth, a monthly supervisory observation checklist—adapted from the Reach Up observers’ checklist—was introduced to provide continuous quality monitoring between training events, enabling supervisors to detect performance gaps and address them through targeted coaching rather than waiting for the next formal training cycle. Together, these components are designed to shift the program from reliance on periodic, centrally delivered training toward a self-sustaining State and municipal-level system capable of maintaining visit quality despite inevitable staff turnover.Limitations of study

The study’s design imposes limitations. Firstly, the pre-post design with no control group precludes being able to determine whether the observed changes to the quality of home visits are due to the implementation bundle or other external factors. Furthermore, the brief interval between the intervention delivery and the subsequent assessments might not adequately capture any decline in knowledge and performance over time. Across the study, six checklist raters conducted the pre- and post-training observations and ratings. Checklist raters were not blinded to whether an observation occurred pre- or post-training; however, we used external raters who were not involved in the project. This limitation could potentially introduce expectancy bias into scoring. Because KIIs and FGDs were facilitated by the study team, acceptability findings may be subject to social desirability bias. Although we used neutral questioning and explicitly solicited negative feedback, participants may have been more likely to report favorable perceptions in a study-facilitated context. Future studies could further mitigate this risk by using independent facilitators and/or anonymous quantitative acceptability measures alongside qualitative methods. Acceptability was assessed exclusively using qualitative methods, which enabled rich explanation of what enhanced or reduced acceptability but did not support a pre-specified numeric acceptability threshold. Future evaluations can pair qualitative findings with validated quantitative acceptability measures and pre-defined decision rules for scale-up. The study used purposeful sampling to ensure diversity of respondents within a small sample size and thus may differ from the broader population of HVs in ways that are unforeseen. Therefore, the study is limited in its ability to conclude that the findings are generalizable. We therefore encourage the replication of our study in a larger and more rigorous study design. Despite some limitations, we fulfilled the standards for an implementation feasibility trial so the findings can be used to inform a larger trial.

Conclusion

The implementation feasibility trial reported here shows that the implementation strategies developed to address barriers related to home visitation content, training, and supervision were acceptable, feasible, and associated with improved quality of home visits. The findings suggest that the bundle improved quality by changing how front-line work is designed, learned, and supported through three transferable design principles. First, providing step-by-step visit guidance paired with an age-appropriate activities compendium reduced excessive discretion, with HVs and supervisors most appreciating the ease of selecting activities and the clarity of structured visit guidelines. Second, the use of demonstration and simulation-based training methods externalized what quality home visiting looks like in practice, with participants reporting that the training gave them confidence and a clear understanding of each step of the visit. Third, structured supervision instruments and monitoring forms embedded feedback loops into routine practice, enabling consistent quality assurance across diverse municipal settings. The findings will be further tested in a larger trial and used to improve the implementation and impact of PCF. The three design principles identified, reducing excessive discretion, externalizing quality through experiential training, and embedding feedback loops through structured supervision, may also generalize to other community worker training programs facing similar implementation constraints, including heterogeneous staff preparation, high turnover, and limited supervisory capacity, regardless of the specific curriculum used.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary Material 1 ^{(19.9KB, docx)}

Supplementary Material 2 ^{(41.1KB, xlsx)}

Author contributions

AB, CMW, ACSO, NP, LB, ALRC, JLS, DFSC, contributed to the design and implementation of the study, revised and approved the manuscript. ACSO, NP, LB, ALRC, and DFSC conducted the interviews. CMW, ALRC, and AB conducted the analysis and accessed and verified the data reported in the manuscript. SCL, JH, HP, and SW advised on study design and revised the manuscript. CMW and AB wrote manuscript. AB supervised the Project and received the funding.

Funding

The study was funded by the LEGO Foundation and the Conselho Nacional de Ciência e Tecnologia (CNPq) grant N^º 315984/2021-0. The funders had no participation in study design, analysis or result’s interpretation.

Data availability

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Declarations

Ethical approval and consent to participate

The current study received ethical approval from the PI’s Institutional IRB, University of São Paulo Medical School Hospital- HC-FMUSP (CAPPESQ) under protocol number CAAE 51767121.10000.0068. All participants provided written informed consent following a complete description of the study, before participating in the study. All transcripts and interview results were without any identifiable information.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.