Frequently Asked Questions
How does a model get on the HomVEE list?
The HomVEE “list” refers to models HomVEE has reviewed and found to meet the HHS criteria for evidence-based models. HomVEE’s annual review typically includes review of both models that are not yet evidence based (Track 1) and updates to the research on models that have previously been designated as evidence based (Track 2).
HomVEE uses a systematic process to select models for review. Track 1 models are selected using a prioritization process. HomVEE conducts a thorough literature review and scores models based on a combination of manuscript and model characteristics. Models are ranked by points and the highest-ranking models are selected for review as resources allow. (For more information, see response to the next question “How are models prioritized and reviewed by HomVEE?”) HomVEE reviews manuscripts according to our published procedures and standards. When a model is reviewed, findings from well-designed research are reported in detail in each model report and used to assess whether a model meets the HHS criteria. As of 2023, Track 2 models are reviewed on a schedule rather than a prioritization process. Regardless of whether the model meets the HHS criteria, information about each reviewed model can be accessed on the HomVEE website via the Model Search Page. A list of models HomVEE has reviewed, and whether they meet the HHS criteria, is also available in the in the summary brief, available on the HomVEE Summary Page.
How are models prioritized and reviewed by HomVEE?
For models that are not yet evidence based (Track 1), HomVEE will select models to review by calculating a prioritization score using a combination of model and manuscript characteristics. Prioritization scoring assigns points based on various factors, including (1) number and design of eligible impact studies, (2) sample sizes and sample characteristics of the impact studies, and (3) characteristics of the model. After a model is selected for review, HomVEE will apply Version 2.1 standards to review all research that is unreviewed or was previously reviewed under Version 1 standards. See the Version 2.1 Handbook of Procedures and Evidence Standards located on the Methods and Standards section of the website for more information on these processes.
As of 2023, models that are already evidence based (Track 2) are reviewed on a schedule instead of using a prioritization process. Previously reviewed research about these models is not re-reviewed for these updates.
How does HomVEE screen research for review?
HomVEE screens all research identified through its annual call for research and literature review to identify which manuscripts are eligible for review according to HomVEE’s published procedures and standards. Specific screening criteria can be found in Chapter 2 of the Version 2.1 Handbook of Procedures and Evidence Standards located on the Methods and Standards section of the website. Once manuscripts are screened in, manuscripts about impact studies contribute to prioritization rankings. Research on models that are not prioritized for review in a given year remains in the HomVEE database for consideration in future years.
Beginning in 2021, HomVEE will only review research published or prepared in the past 20 years. For models that are not yet evidence based (Track 1), HomVEE will only review research published within 20 years of the review year. If a Track 1 model was previously reviewed, research older than 20 years will be removed from the website when that model is next prioritized. For models that are evidence based (Track 2), no research will be removed from the website.
May I submit research on my model for review?
Yes, HomVEE issues a call for research every year in August that is open through September. The call is sent to relevant electronic mailing lists and is also posted on the HomVEE website homepage with instructions on how to submit research. Research can be submitted at any time, but if it is submitted outside of the call window, it will be screened the following year.
HomVEE aims to treat all models consistently and fairly and to have a complete picture of all observed effects for a model. Therefore, HomVEE has a systematic process for identifying all relevant research and prioritizing models for review based on the available empirical evidence. Accepting new information, studies, or research during the course of the review would significantly delay HomVEE’s annual review process. For these reasons, HomVEE cannot review specific manuscripts on request. More details on this process are available in Chapter 2 of the Version 2.1 Handbook of Procedures and Evidence Standards Methods and Standards section of the website.
Please sign up for the HomVEE mailing list to be notified of the call for research and other HomVEE-related news. To join the email list, find the "Join the HomVEE email list" box on the bottom right side of the Home page or the left side of the What's New page, enter your email address and click the Subscribe button.
May I appeal the review results?
You may request a re-review if you think that (1) in applying the criteria to determine whether a particular model is evidence based, HomVEE made one or more errors; and (2) if these errors were addressed, the model would be evidence based. Specifically, you may request reconsideration of the evidence-based determination based on misapplication of the HHS criteria, missing information, or errors on the HomVEE website. These concerns should be described in detail and submitted to: HomVEE@acf.hhs.gov. Pending approval from HHS, an independent re-review team will conduct a new review of the manuscript(s) in question. Re-reviews are conducted using the procedures and standards in place at the time of the original review. For more information on the re-review process, see Chapter 2 of the Version 2.1 Handbook of Procedures and Evidence Standards on the Methods and Standards section of the website.
How long does it take to re-review models that have submitted an appeal?
HomVEE aims to issue a final decision as to whether the standards were accurately applied within 60 days of the submission of the request for review. All requests must be submitted to HomVEE@acf.hhs.gov. Once a decision is made, the requester will be notified, and any necessary adjustments will be made to reports on the HomVEE website.
Are models on the HomVEE list automatically eligible for MIECHV funding?
A HomVEE designation as an evidence-based model does not guarantee that a model is eligible to be implemented with MIECHV funding. To be eligible for implementation as an evidence-based model with MIECHV funding, a model must both meet HHS criteria for evidence of effectiveness (as determined by HomVEE) and meet all other statutory requirements for model eligibility (as determined by the Health Resources and Services Administration [HRSA] at HHS). In addition, MIECHV’s authorizing statute allows awardees to utilize a portion of their MIECHV funding for a model that qualifies as a promising approach. For additional information on the MIECHV Program, see the HRSA website.
Which study designs are eligible for review?
HomVEE considers two types of study designs to be reliable for answering the question of whether an early childhood home visiting model impacts the outcomes of children and families: (1) randomized controlled trials (RCTs) and (2) three quasi-experimental designs (QEDs): single-case designs (SCDs), regression discontinuity designs (RDDs) and non-experimental comparison group designs (NEDs). These are the only study designs that are eligible for review by HomVEE.
Why can research with some designs rate higher than research with other designs?
Study designs vary in their relative risk of bias – that is, they vary in the extent to which researchers can be confident that impacts are due to home visiting rather than other factors. HomVEE accounts for risk of bias when assigning ratings to research. Research with a higher risk of bias receives a lower rating. For more details, please see Chapter 3 of the Version 2.1 Handbook of Procedures and Evidence Standards located on the Methods and Standards section of the website. HomVEE routinely contacts authors if additional details are needed to assess the appropriate rating to assign to the manuscript.
What types of analyses or contrasts are not eligible for review?
HomVEE focuses its resources on reviewing manuscripts about impact studies that answer the review’s core question of whether an early childhood home visiting model is effective. Research that answers other questions is not eligible for review by HomVEE. For example, questions about for whom and under what circumstances a model is effective are valuable to the field but beyond the scope of the HomVEE review.
Research evaluating the impact of an isolated model feature or group of features is generally ineligible for HomVEE’s annual review. Additionally, analyses designed to answer questions other than whether a model is effective are generally ineligible for review. A longer discussion of these types of analyses and exceptions in which HomVEE would review them can be found in Chapter 3 of the Version 2.1 Handbook of Procedures and Evidence Standards located on the Methods and Standards section of the website.
Does HomVEE provide guidelines authors can refer to when writing up their research findings?
HomVEE’s Reporting Guide for Authors provides guidance about how to describe each eligible research design and how to report findings in a way that is clear, complete, and transparent. Reporting the information described in the Reporting Guide for Authors is considered a best practice in general, but it can also help HomVEE reviewers determine the appropriate rating to assign to the manuscript.
How does HomVEE define an early childhood home visiting model?
For the purposes of the HomVEE review, an early childhood home visiting model is an intervention in which trained home visitors meet with expectant parents or families with young children to deliver a specified set of services through a specified set of interactions. These programs are voluntary interventions that are either designed or adapted and tested for delivery in the home. During the visits, home visitors aim to build strong, positive relationships with families to improve child and family outcomes. Services may be delivered on a schedule that is defined or can be tailored to meet family needs. A model has a set of fidelity standards that describe how the model is to be implemented.
Models reviewed by HomVEE must serve pregnant people or families with children from birth to kindergarten entry (that is, up until their sixth birthday), and the primary service delivery strategy must be home visiting. In addition, the model must have research that examines its effects in at least one of eight outcome domains.
Are maternal/infant health home visiting models, not just early childhood ones, included in the review?
Yes, any model that meets the definition of the early childhood home visiting model is included in the review, and this may include models that enroll people during pregnancy and aim to improve maternal health, infant health, and birth outcomes. For models with well-designed research that meets HomVEE’s published standards, detailed information about the theoretical approach, intended population, and targeted outcomes can be found via the implementation link on the Model Search Page on HomVEE’s website. That page also has a search function that allows the user to filter all models by population served. Detailed information about maternal and child health outcomes can be found in the “Effects shown in research” tab of each model effectiveness research report.
How does HomVEE treat virtual and telehealth interventions and adaptations?
HomVEE is working with federal agencies and other interested individuals and groups to develop guidelines for HomVEE’s review of research on virtual and telehealth interventions and adaptations, including model adaptations made in response to the COVID-19 pandemic. Pending finalization of these guidelines, HomVEE is collecting and holding manuscripts about interventions that are purely or primarily virtual.
HHS criteria for evidence-based models
What are the HHS criteria for evidence-based models?
HomVEE uses the term “evidence-based model” to refer specifically to a model that meets HHS criteria developed based on statutory requirements in the authorizing legislation for the MIECHV Program. HomVEE recognizes that other systematic reviews may use different criteria to evaluate evidence of effectiveness. Thus, an evidence-based model in the context of HomVEE might or might not meet requirements for evidence of effectiveness according to other systematic reviews. The HHS criteria for an evidence-based early childhood home visiting service delivery model are designed to ensure confidence in model impacts through replicated findings from well-designed research.
How does HomVEE apply HHS criteria for evidence-based early childhood service delivery models?
HomVEE assesses whether each model meets the HHS criteria for an “evidence-based early childhood service delivery model.” To operationalize the HHS criteria related to studies, and because study findings may be reported across several manuscripts, HomVEE rates manuscripts based on the highest-rated finding reported in that manuscript. Any high- or moderate-rated finding from a study about a model is considered as part of the evidence base for that model. Notably, for models with research solely from either RCT or SCD studies, additional criteria apply (see the HHS criteria). The additional criteria for RCTs to be from peer-reviewed journal articles and to have sustained findings align with MIECHV Program statutory requirements. The HHS criteria for an evidence-based model have no additional requirements for RDD or NED studies. A model may be evidence based on the strength of subgroup findings alone only if the research about it satisfies all of the subgroup criteria.
Is a model required to have evidence from an RCT in order to be evidence-based according to HHS criteria?
No. A model may be evidence-based, according to HHS criteria, on the strength of either RCT research or QED research (including non-experimental comparison group, single-case, and regression discontinuity designs). The research must be of moderate or high quality based on HomVEE’s published standards. Additional HHS criteria apply when the research uses an RCT design. For details, please see the HHS criteria for evidence-based early childhood home visiting service delivery models.
Where can I find a list of models that meet the HHS criteria for evidence-based models?
A full list of models reviewed by HomVEE, and whether they meet the HHS criteria, is available on the HomVEE website via the Model Search Page. The information is also available in the summary brief, available on the HomVEE Summary Page. Notably, a HomVEE designation as an evidence-based model does not guarantee that a model is eligible to be implemented with MIECHV funding (see above, “Are models on the HomVEE list automatically eligible for MIECHV funding?”).
Does HomVEE consider the magnitude of impacts?
The HHS criteria do not consider the magnitude of impacts in determining whether a model has evidence of effectiveness.
Even though magnitude is not considered in the HHS criteria, HomVEE reports standard effect sizes for findings rated high and moderate when they were available in the manuscripts or the HomVEE team had enough information to calculate them. Effect sizes can be found in the "Effects shown in research" section of each model effectiveness research report. The reports can be accessed through the Model Search Page.
Information available on the website
Is there a list of models reviewed but that did not meet the requirements?
Is information on implementation of models available?
Information on implementation of models with manuscripts about high- and moderate-quality impact studies is available in the implementation profiles. The implementation profiles give an overview of the model and information about developers’ input on the following: theoretical approach, implementation support availability, intended population, targeted outcomes, model services, requirements, and model contact information. These profiles can be accessed on the Model Search Page.
How can a model developer request that HomVEE update its contact information?
Model developers may contact HomVEE at any time to update contact information on the website. HomVEE aims to publish updates on a reasonable timeline. Please see our Contact Us page to provide updated contact details. HomVEE will publish these updates within a reasonably short timeframe, rather than waiting for the next full HomVEE review of the model.
Does HomVEE categorize research that is in progress on these models?
No. HomVEE does not have consistent information about research underway on home visiting models. HomVEE users who are seeking information about research in progress on specific models should contact the model developer directly.
Study sample diversity
What is the racial/ethnic and income diversity of study samples in the HomVEE review?
Overall, the manuscripts about high- and moderate-quality impact studies included in the HomVEE review include families from multiple racial/ethnic groups, and most of the samples include families with low incomes. More information on study characteristics can be found for each high- and moderate-rated manuscript about a model, via the “Information about research reviewed” tab in any Model Effectiveness Research Report, accessed through the Model Search Page.
Does HomVEE provide information on the effectiveness of early childhood home visiting models for specific racial/ethnic groups?
Although study samples included in the HomVEE review are quite diverse, most of the manuscripts about high- and moderate-quality impact studies aggregate the results across racial/ethnic groups. Thus, the available evidence generally does not reveal whether these models are more or less effective with one group or another.
Further, the sample sizes of most studies may not provide sufficient statistical power to detect effects for specific racial/ethnic subgroups. In other words, even if there are sizeable effects of the intervention for a particular racial/ethnic group, these may not be detected because of small sample sizes for that subgroup.
Because HomVEE’s mission is to identify evidence-based models, and HHS’ criteria require replication before subgroup research can be part of the evidence base, the annual review only reports findings from impact research on replicated subgroups. Replication provides more confidence that findings were not observed by chance. HomVEE uses the same set of standards to rate the quality of research for all findings on a replicated subgroup. For example, if the subgroup replication straddled the timing of an update to HomVEE standards, HomVEE would review both sets of subgroup findings using the newest standards (even if other, full-sample findings from the older manuscript were reviewed using older HomVEE standards).
HomVEE recognizes that the effects of models for different populations is of interest to the home visiting field. Although HomVEE only reports findings for replicated subgroups, HomVEE lists the subgroups examined in each manuscript beginning with its 2021 annual review. HomVEE does not report details on the findings or the quality of the study design until the subgroup is replicated.
More information on study characteristics, including the race/ethnicity of a study sample, can be found for each manuscript about a high- or moderate-rated study on a model via the "Information about research reviewed" tab in any Model Effectiveness Research Report, accessed through the Model Search Page. If a model has been tested with a replicated subgroup, HomVEE summarizes the subgroup findings as part of that model’s effectiveness research report.
Are there any studies specific to American Indian/Alaska Native populations?
In addition to the main HomVEE review, HomVEE periodically updates a review of models that were implemented with tribal communities or included substantial proportions of American Indian/Alaska Native families in the study samples. The results of this review are presented in a report that can be accessed on the Tribal Home Visiting page.
Were studies in the HomVEE review conducted in both rural and urban communities?
Several of the models reviewed by HomVEE have been studied with families in a mix of urban and rural communities. Results for families from rural and urban areas are generally aggregated across groups. More information on study characteristics, including the setting, can be found for each manuscript about high- or moderate-rated study on a model via the Information about research reviewed tab in any Model Effectiveness Research Report, accessed through the Model Search Page.
What is a single-case design (SCD)?
Studies that use a single-case design (SCD) measure outcomes for cases (such as a child or family) repeatedly during multiple phases of a study to determine the success of an intervention. SCDs aim to rigorously test the effectiveness of an early childhood home visiting model using a relatively small sample. The number of phases in the study will depend on the research questions, intervention, and outcome(s) of interest. Details are available in the Version 2.1 Handbook of Procedures and Evidence Standards located on the Methods and Standards section of the website.
How does HomVEE interpret findings from SCDs?
Whenever possible, the Home Visiting Evidence of Effectiveness review (HomVEE) will use SCD findings across cases to calculate a design-comparable effect size (D-CES). The D-CES produces a measure of the difference between the intervention and comparison conditions. Because of methodological limitations, researchers cannot calculate a D-CES for certain SCD designs. As calculations for these types of designs become available in the methodological literature, HomVEE might calculate the D-CES for these designs in the future.
How does HomVEE apply the U.S. Department of Health and Human Services (HHS) criteria to SCDs? Can these study designs contribute to the summary of evidence for a particular model?
HomVEE will apply the HHS criteria to SCDs in the same way it applies the criteria to other group designs. If an SCD manuscript receives a rating of moderate or high based on the HomVEE standards, its findings are assessed against the HHS criteria using design-comparable effect sizes (for more information, see response to the FAQ “How does HomVEE interpret findings from SCDs?”).
Are SCDs as rigorous a study design as RCTs or NEDs?
Although SCDs typically have small sample sizes, they can produce rigorous findings. HomVEE developed review standards for SCDs (as it has for group designs) to ensure that research contributing to a model’s summary of evidence has a sufficiently rigorous design to confirm that the findings are attributable, at least partly, to the home visiting model the researchers examined. Similar to other designs eligible for HomVEE review, the SCD standards ensure that the findings have sufficient internal validity.
Does it matter to the evidence base that SCD research typically has far fewer participants than other types of effectiveness research?
Similar to other designs eligible for HomVEE review, well-designed SCD research can help researchers learn whether the home visiting model is effective based on a small number of participants. HomVEE’s standards for all designs focus on the question of internal validity: Does the model work? To address this question, HomVEE’s standards are designed to assess internal validity – that is, whether the study finds evidence of impacts with limited bias. All of the research designs eligible for HomVEE review could plausibly find impacts eligible for high or moderate ratings with small sample sizes.
Can researchers use SCDs to address research questions related to child development? How do SCDs differentiate between changes resulting from development and changes resulting from an intervention?
Researchers can use SCDs to measure outcomes related to child development even though the study design does not have a separate comparison group. That is, there are features of SCD research that provide comparison conditions, so researchers can determine whether the effects they observe are a result of an intervention. See the “Single-Case Design Research Methods” brief on the HomVEE website for more information.