Dozier, M., Peloso, E., Lindhiem, O., Gordon, M. K., Manni, M., Sepulveda, S., Ackerman, J., Bernier, A., & Levine, S. (2006). Developing evidence-based interventions for foster children: An example of a randomized clinical trial with infants and toddlers. Journal of Social Issues, 62(4), 767–785. https://doi.org/10.1111/j.1540-4560.2006.00486.x

Type of Study: Randomized controlled trial
Number of Participants: 164

Population:

• Age — 3.6–39.4 months
• Race/Ethnicity — 63% African American, 32% White, and 5% Biracial
• Gender — 51% Female
• Status — Participants were children in foster care.

Location/Institution: Mid-Atlantic, U.S.

Summary: (To include basic study design, measures, results, and notable limitations)
The purpose of the study was to test the effectiveness of Attachment and Biobehavioral Catch-up (ABC), to target relationship formation in young children in the foster care system. Participants were randomly assigned to receive either the ABC intervention or a control intervention. Measures utilized include the Parent’s Daily Report (PDR/IT), saliva samples, and cortisol assays. Results indicate that children in the experimental intervention group had lower cortisol values than children in the control intervention. Also, the experimental intervention parents reported fewer behavior problems. Limitations include small sample size, length of follow-up, and lack of generalizability of findings due to ethnicity and age.

Length of controlled postintervention follow-up: 1 month.

Dozier, M., Peloso, E., Lewis, E., Laurenceau, J., & Levine, S. (2008). Effects of an attachment based intervention on the cortisol production of infants and toddlers in foster care. Development and Psychopathology, 20(3), 845–859. https://doi.org/10.1017/S0954579408000400

Type of Study: Randomized controlled trial
Number of Participants: 141

Population:

• Age — 15–24 months
• Race/Ethnicity — ABC: 81% African American, 17% White/Non-Hispanic, and 2% Hispanic; DEF: 66% African American, 29% White/Non-Hispanic, and 5% Hispanic; Comparison: 56% White/Non-Hispanic, 35% African American, 5% Hispanic, and 4% Asian American
• Gender — ABC: 59% Female; DEF: 43% Female; Comparison: 44% Female
• Status — Participant were children in foster care.

Location/Institution: University of Delaware

Summary: (To include basic study design, measures, results, and notable limitations)
The purpose of the study was to assess the effectiveness of Attachment and Biobehavioral Catch-up (ABC) with regards to hypothalamus-pituitary-adrenal (HPA) functioning. Children were randomly assigned to receive the ABC intervention or to a treatment control group which received the Developmental Education for Families (DEF) program. A no-treatment comparison group of children who had never been in foster care was also included. Measures utilized include the Strange Situation and salivary cortisol assays. Results indicate that children in the ABC intervention and comparison group showed lower initial values of cortisol than children in the treatment control group, considering arrival at lab as initial values. Groups did not differ significantly in change over time. Limitations include small sample size, lack of generalizability to other populations, and lack of follow-up.

Length of controlled postintervention follow-up: None.

Dozier, M., Lindhiem, O., Lewis, E., Bick, J., Bernard, K., & Peloso, E. (2009). Effects of a foster parent training program on young children's attachment behaviors: Preliminary evidence from a randomized clinical trial. Child and Adolescent Social Work Journal, 26(4), 321–332. https://doi.org/10.1007/s10560-009-0165-1

Type of Study: Randomized controlled trial
Number of Participants: 46

Population:

• Age — 3.6–39.4 months
• Race/Ethnicity — 63% African American, 26% Non-Hispanic/White, 7% Biracial, and 3% Hispanic
• Gender — 50% Female
• Status — Participants were children in foster care.

Location/Institution: Two mid-Atlantic states

Summary: (To include basic study design, measures, results, and notable limitations)
The purpose of the study was to assess the effectiveness of Attachment and Biobehavioral Catch-up (ABC) on children’s attachment behaviors. Participants were randomly assigned to receive the Attachment and Biobehavioral Catch-up (ABC) intervention or to a comparison group which received the Developmental Education for Families (DEF) program. Results indicate that children whose parents received the ABC intervention condition showed significantly less avoidance than children in the DEF group. Limitations include the small sample size, the brief timeframe, lack of standardized measures, and the reliance on parental report.

Length of controlled postintervention follow-up: 1 month.

Bernard, K., Dozier, M., Bick, J., Lewis-Morrarty, E., Lindhiem, O., & Carlson, E. (2012). Enhancing attachment organization among maltreated infants: Results of a randomized clinical trial. Child Development, 83(2), 623–636. https://doi.org/10.1111/j.1467-8624.2011.01712.x

Type of Study: Randomized controlled trial
Number of Participants: 120 children and 113 parents

Population:

• Age — Children: 1.7–21.4 months; Parents: 15.7–47.0 years
• Race/Ethnicity — Children: 61% African American, 20% Biracial, 11% White/Hispanic, and 8% White/Non-Hispanic; Parents: 61% African American, 15% White/Hispanic, 15% White/Non-Hispanic, and 9% Biracial
• Gender — Children: 58% Male and 42% Female; Parents: 98% Female and 2% Male
• Status — Participants were parents with children who were referred by agencies working with child protective services.

Location/Institution: Large mid-Atlantic city

Summary: (To include basic study design, measures, results, and notable limitations)
The purpose of the study was to examine the efficacy of Attachment and Biobehavioral Catch-up (ABC). Participants were randomly assigned to receive either the ABC intervention or a control intervention that received the Developmental Education for Families (DEF) program. Measures utilized include the Strange Situation. Results indicate that children in the ABC intervention group showed significantly lower rates of disorganized attachment (32%) and higher rates of secure attachment (52%) relative to the control intervention (57% and 33%, respectively). Limitations include the use of the Strange Situation exercise outside of the age groups for which it has been validated, lack of examination of the possible effects of the comparison intervention, lack of access to child protective services records, and length of follow-up.

Length of controlled postintervention follow-up: 1 month.

Lewis-Morrarty, E., Dozier, M., Bernard, K., Terracciano, S. M., & Moore, S. V. (2012). Cognitive flexibility and theory of mind outcomes among foster children: Preschool follow-up results of a randomized clinical trial. Journal of Adolescent Health, 51(2), S17–S22. https://doi.org/10.1016/j.jadohealth.2012.05.005

Type of Study: Randomized controlled trial
Number of Participants: 61

Population:

• Age — Children: 4–6 years (Mean=60.3 months); Parents: Not specified
• Race/Ethnicity — Children: 43% African American, 36% European American, and 21% Hispanic, Asian American, or Biracial; Parents: 57% European American, 39% African American, and 3% Asian American
• Gender — Children: 51% Male; Parents: 100% Female
• Status — Participants were children in foster care when they were infants.

Location/Institution: Two mid-Atlantic states

Summary: (To include basic study design, measures, results, and notable limitations)
The study used a subsample from Dozier et al. (2009). The purpose of the study was to examine longer term effects of the Attachment and Biobehavioral Catch-up (ABC) intervention. Participants were randomly assigned to receive the ABC intervention or a control intervention that received the Developmental Education for Families (DEF) program and were compared to children who had never been in foster care. Measures utilized include the Dimensional Change Card Sort (DCCS), the Peabody Picture Vocabulary Test, 3rd ed. (PPVT-III), and the Brief Symptom Inventory. Results indicate that preschool-aged foster children who received the ABC intervention showed stronger cognitive flexibility and theory of mind skills, relative to foster children who received a control intervention. Foster children who received the ABC intervention showed capabilities in these areas that were not significantly different from a comparison group of children who were never in foster care. Limitations include the small sample size and the inequality of the three groups on several demographic variables. In addition, there is some concern about whether the measures used at the 2-year follow-up were appropriate to show sustained effect, due to differences between the baseline and follow-up measures.

Length of controlled postintervention follow-up: Approximately 2 years.

Bick, J., & Dozier, M. (2013). The effectiveness of an attachment-based intervention in promoting foster mothers' sensitivity toward foster infants. Infant Mental Health Journal, 34(2), 95–103. https://doi.org/10.1002/imhj.21373

Type of Study: Randomized controlled trial
Number of Participants: 96 foster mother-infant dyads

Population:

• Age — Children: 1–22 months; Adults: 24–74 years
• Race/Ethnicity — Children: 59% African American, 28% White, 6% Hispanic, 6% Biracial, and 1% Asian; Adults: 46% White, 43% African American, 7% Hispanic, and 4% Biracial
• Gender — Children: 48% Female; Adults: 100% Female
• Status — Participants were foster mothers and infants in foster care.

Location/Institution: Mid-Atlantic, U.S.

Summary: (To include basic study design, measures, results, and notable limitations)
The purpose of the study was to examine the effectiveness of the Attachment and Biobehavioral Catch-up (ABC) intervention to promote sensitive caregiving behavior among foster mothers. Participants were randomly assigned to ABC or the control group that received Developmental Education for Families (DEF) intervention. Measures utilized include the use of study developed measures regarding material sensitivity. Results indicate that foster mothers who were assigned to ABC showed greater improvements in their sensitivity from pre-intervention to postintervention assessment time points when compared with foster mothers who were assigned to the control intervention. Limitations include the small sample size, lack of standardized measures, and the limited nature of the assessment.

Length of controlled postintervention follow-up: Varied by age of child, assessed at age=24 months.

Bernard, K., Simons, R., & Dozier, M. (2015). Effects of an attachment-based intervention on child protective services-referred mothers' event-related potentials to children's emotions. Child Development, 86(6), 1673–1684. https://doi.org/10.1111/cdev.12418

Type of Study: Randomized controlled trial
Number of Participants: 70 parent/youth dyads

Population:

• Age — Children: Not specified; Adults: Mean=31.6 years
• Race/Ethnicity — Children: Not specified; Adults: 74% African American, 16% White/Non-Hispanic, 6% Hispanic, and 4% Biracial
• Gender — Children: 58% Male and 42% Female; Adults: 100% Female
• Status — Participants were children and parents identified as at risk for neglect in a diversion from foster care program.

Location/Institution: Mid-Atlantic, U.S.

Summary: (To include basic study design, measures, results, and notable limitations)
The purpose of the study was to examine the neurobiology of maternal sensitivity to children’s emotions among mothers involved with Child Protective Services (CPS) and low-risk comparison mothers. Participants were randomly assigned to the Attachment and Biobehavioral Catch-up (ABC) intervention or the control, Developmental Education for Families (DEF) intervention. Measures utilized include Electroencephalogram (EEG) activity, Qualitative Scales of the Observational Ratings of the Caregiving Environment, and Brief Symptoms Inventory. Results indicate that CPS-referred ABC mothers and low-risk comparison mothers showed a larger enhancement of event-related potential (ERP) responses for emotional faces relative to neutral faces than CPS-referred control mothers. Additionally, the magnitude of ERP responses to emotional faces was associated with observed maternal sensitivity. Limitations include the small sample size, variations in the families’ maltreatment experiences, and lack of follow-up.

Length of controlled postintervention follow-up: None.

Bernard, K., Lee, A. H., & Dozier, M. (2017). Effects of the ABC intervention on foster children's receptive vocabulary: Follow-up results from a randomized clinical trial. Child Maltreatment, 22(2), 174-179. https://doi.org/10.1177/1077559517691126

Type of Study: Randomized controlled trial
Number of Participants: 52 parent/child dyads

Population:

• Age — Children: 2.85–3.87 years; Adults:19.0–58.6 years
• Race/Ethnicity — Children: 29 African American, 15 Caucasian, 4 Biracial, 3 Hispanic, and 1 Asian American; Adults: 24 African American, 23 Caucasian, 3 Hispanic, and 2 Biracial
• Gender — Children: 56% Female and 44% Male; Adults: 94% Female
• Status — Participants were children and parents referred by caseworkers at foster care agencies and were involved in the child welfare system.

Location/Institution: Mid-Atlantic, U.S.

Summary: (To include basic study design, measures, results, and notable limitations)
This study used a subsample from Bick & Dozier (2013). The purpose of the study was to examine whether a parenting intervention administered in infancy improved preschool receptive language skills in children involved with the child welfare system. Participants were randomly assigned into the Attachment and Biobehavioral Catch-up (ABC) intervention or the control, Developmental Education for Families (DEF) intervention. Measures utilized include the Peabody Picture Vocabulary Test, 3rd ed. (PPVT-III). Results indicate that infants who received the ABC intervention scored significantly higher on a test of receptive vocabulary at age 36 months than infants who received a control intervention. Limitations include the small sample size, attrition due to children changing placements, and assessments of ABC intervention fidelity were not included.

Length of controlled postintervention follow-up: 3 years.

Yarger, H. A., Bernard, K., Caron, E. B., Wallin, A., & Dozier, M. (2020). Enhancing parenting quality for young children adopted internationally: Results of a randomized controlled trial. Journal of Clinical Child and Adolescent Psychology, 49(3), 378–390. https://doi.org/10.1080/15374416.2018.1547972

Type of Study: Randomized controlled trial
Number of Participants: 120

Population:

• Age — Children: 6.8–48.4 months (Mean=21.9 months); Primary Caregivers: 26.2–51.1 years (Mean=39.7 years)
• Race/Ethnicity — Children: ABC: 68% Asian American, 15% White, 10% African American, 5% Biracial, and 2% Other; DEF: 57% Asian American, 25% White, and 18% African American; Primary Caregivers: ABC: 98% White and 2% Asian American, DEF: 92% White, 5% Asian American, 2% Af
• Gender — Children: 53% Female; Primary Caregivers: 94% Female
• Status — Participants were internationally adopted children and their adoptive parents.

Location/Institution: Mid-Atlantic region

Summary: (To include basic study design, measures, results, and notable limitations)
The purpose of the study was to assess whether parents randomized to receive Attachment and Biobehavioral Catch-up (ABC) demonstrated significant improvements in parenting quality when compared to parents receiving a control intervention. Participants were randomly assigned to receive either ABC or a control intervention, Developmental Education for Families (DEF). Measures utilized include of study developed measures and a questionnaire about the child’s adoption history. Results indicate that parents who received ABC showed better parenting quality at postintervention than parents who received the control intervention, and these effects persisted at a 2-year follow-up. Limitations include low generalizability due to parent gender, heterogeneity of children’s preadoption history, lack of standardized measures, and small effect sizes.

Length of controlled postintervention follow-up: Varied based upon outcome.

Zajac, L., Raby, K. L., & Dozier, M. (2020). Sustained effects on attachment security in middle childhood: results from a randomized clinical trial of the Attachment and Biobehavioral Catch-up (ABC) intervention. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 61(4), 417–424. https://doi.org/10.1111/jcpp.13146

Type of Study: Randomized controlled trial
Number of Participants: 100

Population:

• Age — Children: ABC: Mean=9.45 years, DEF: Mean=9.46 years; Parents: ABC: Mean=38.71 years, DEF: Mean=37.14 years
• Race/Ethnicity — Children: 80% Non-Hispanic or Latino, 66% African-American, 20% Hispanic or Latino, 19% Biracial, and 15% Caucasian; Parents: Not specified
• Gender — Children: 52% Male; Parents: 97% Female
• Status — Participants were Child Protective Services (CPS)-referred children. 

Location/Institution: A large Mid-Atlantic city

Summary: (To include basic study design, measures, results, and notable limitations)
This study used a subsample from Bernard et al. (2012). The purpose of the study was to examine whether receiving the Attachment and Biobehavioral Catch-Up (ABC) intervention during infancy led to improvements in perceived attachment security in middle childhood. Participants were randomly assigned to ABC or Developmental Education for Families (DEF). Measures utilized include the Kerns Security Scale. Results indicate that children whose parents received ABC reported higher levels of attachment security on the Kerns Security Scale at age nine than children whose parents had received the control intervention. Limitations include not looking at potential mediators of ABC’s effect and not considering child-specific factors.

Length of controlled postintervention follow-up: Varied by age of child, assessed at age=9 years.