Research
From tightly controlled randomized control trials (RCTs) to ongoing clinic-based research, our science shows that CPP promotes healing for caregivers and children exposed to trauma.
Overview
Decades of research demonstrate that Child-Parent Psychotherapy supports healthy development in infants and young children exposed to trauma as well as their caregivers. For example, compared to families who do not receive CPP, children and caregivers who receive CPP have stronger, more secure relationships and lower levels of mental health problems, including post-traumatic stress symptoms. Children show better cognitive functioning, and caregivers report lower levels of parenting stress. Improvements in the caregiver-child relationship have long-lasting impacts, translating to higher-quality peer relationships and reduced problem behavior in children measured eight years after they received CPP.
Recent interdisciplinary research suggests that some of these effects may occur because CPP helps reduce the biological effects of chronic stress. Findings show that CPP leads to healthier patterns of cellular aging in children and better stress-system functioning in mothers, which may contribute to long-term improvements in health.
Child Parent Psychotherapy
Randomized Control Trials
Ghosh Ippen, C., Harris, W.W., Van Horn, P., & Lieberman, A.F. (2011). Traumatic and stressful events in early childhood: Can treatment help those at highest risk? Child Abuse and Neglect, 35, 504-513. 10.1016/j.chiabu.2011.03.009
Lieberman, A. F., Ghosh Ippen, C., Van Horn, P. J. (2006). Child-Parent Psychotherapy: Six Month Follow-Up of a Randomized Control Trial. Journal of the American Academy of Child and Adolescent Psychiatry, 45(8), 913-918. 10.1097/01.chi.0000222784.03735.92
Lieberman, A. F., Van Horn, P. J., & Ghosh Ippen, C. (2005). Toward Evidence-Based treatment: Child-Parent Psychotherapy with Preschoolers Exposed to Marital Violence. Journal of the American Academy of Child and Adolescent Psychiatry, 44, 1241-1248. 10.1097/01.chi.0000181047.59702.58
Lieberman, A. F., Weston, D. R., & Pawl, J. H. (1991). Preventive Intervention and Outcome with Anxiously Attached Dyads. Child Development, 62, 199-209.
CPP Application
Guyon‐Harris, K. L., & Humphreys, K. L. (2026). Annual Research Review: Interventions for young children exposed to trauma. Journal of Child Psychology and Psychiatry. https://doi.org/10.1111/jcpp.70121
Ghosh Ippen, C., & Lieberman, A. F. (2024). Child–parent psychotherapy: Acknowledging ruptures in safety and rebuilding the protective shield. In WAIMH Handbook of Infant and Early Childhood Mental Health: Cultural Context, Prevention, Intervention, and Treatment, Volume Two (pp. 293-312). Cham: Springer International Publishing. https://doi.org/10.1007/978-3-031-48631-9_19
Reyes, V., Stone, B., Hernandez Dimmler, M. and Lieberman, A.F. “Child-Parent Psychotherapy: An Evidence-Based Treatment for Infants and Young Children.” Evidence-Based Treatments for Trauma-Related Disorders in Children and Adolescents. Ed. by Marylène Cloitre, Ulrich Schnyder, and Markus A. Landolt. Cham: Springer Nature Switzerland, 2024. 401–421.
Jones-Mason, K., Reyes, V., Noriega, M., & Lieberman, A. F. (2024). Parent-child border separation and the road to repair: addressing a global refugee phenomenon. Attachment & Human Development, 1–36. https://doi.org/10.1080/14616734.2024.2401928
Chu, A. T., Ippen, C. G., Lieberman, A. F. (2021). It’s All About the Relationship: The Role of Attachment in Child-Parent Psychotherapy. Research on Child Adolescent Psychopathology, 49(5):591-593. https://doi.org/10.1007/s10802-020-00741-5
Lieberman, A. F. (2014). Giving Words to the Unsayable: The Healing Power of Describing What Happened. Psychoanalytic Dialogues, 24(3), 277–281. https://doi.org/10.1080/10481885.2014.911606
Lieberman, A. F., Van Horn P. (2013). Infants and Young Children in Military Families: A Conceptual Model for Intervention. Clinical Child and Family Psychology Review, (3):282-93. 10.1007/s10567-013-0140-4
Lieberman, A. F., & Van Horn, P. (2009). Giving Voice to the Unsayable: Repairing the Effects of Trauma in Infancy and Early Childhood. Child and Adolescent Psychiatric Clinics of North America, 18(3), 707–720. 10.1016/j.chc.2009.02.007
Lieberman, A., Van Horn, P., & Ozer, E. (2005). Preschooler Witnesses of Marital Violence: Predictors and Mediators of Child Behavior Problems. Development & Psychopathology, 17(2), 385– 396. https://doi.org/10.1017/s0954579405050182
Effectiveness Studies
Paris, R., Maru, M., Yang, Y., & Garber, K. (2025). Trauma and mental health: Examining psychosocial changes for Latin American immigrant mothers and young children participating in child–parent psychotherapy. Psychological Trauma: Theory, Research, Practice, and Policy.
Lieberman, A. F., & Ghosh Ippen, C. (2024). Engaging the child–parent relationship to treat early trauma: The challenge and promise of scaling with fidelity. Journal of Traumatic Stress, 37(5), 784-789. https://doi.org/10.1002/jts.23077
Sullivan, A. D. W., Merrill, S. M., Konwar, C., Coccia, M., Rivera, L., MacIsaac, J. L., Lieberman, A. F., Kobor, M. S., & Bush, N. R. (2024). Intervening After Trauma: Child-Parent Psychotherapy Treatment Is Associated With Lower Pediatric Epigenetic Age Acceleration. Psychological science, 35(9), 1062–1073. https://doi.org/10.1177/09567976241260247
Hagan, M. J. Brown, D. T., Sulki, M., Ghosh Ippen, C., Bush, N., Lieberman, A. F. (2017). Parent and Child Trauma Symptoms During Child-Parent Psychotherapy: A Prospective Cohort Study of Dyadic Change. Journal of Traumatic Stress, 30, 690-697. 10.1002/jts.22240
Ghosh Ippen, C., Noroña, C. R., & Lieberman, A. F. (2014). Clinical Considerations for Conducting Child-Parent Psychotherapy with Young Children with Developmental Disabilities Who Have Experienced Trauma. Pragmatic Case Studies in Psychotherapy, 10(3). https://doi.org/10.14713/pcsp.v10i3.1870
Perinatal CPP
Effectiveness and Application
Narayan, A. J., Bucio, G. O., Rivera, L. M., & Lieberman, A. F. (2016). Making Sense of the Past Creates Space for the Baby: Perinatal Child-Parent Psychotherapy for Pregnant Women with Childhood Trauma. Zero to Three, 36(5), 22-28.
Lavi, I., Gard, A. M., Hagan, M., Van Horn, P. J., & Lieberman, A. F. (2015). Child-Parent Psychotherapy Examined in a Perinatal Sample: Depression, Post-Traumatic Stress Symptoms and Child Rearing Attitudes. Journal of Social and Clinical Psychology, 34(1), 64-82. https://doi.org/10.1521/jscp.2015.34.1.64
Lieberman, A. F., Díaz, M. A., & Van Horn, P. (2009). Safer Beginnings: Perinatal Child-Parent Psychotherapy for Newborns and Mothers Exposed to Domestic Violence. Zero to Three, 29, 17-22.
Other Empirical Studies
Atzl, V. M., Narayan, A. J., Ballinger, A., Harris, W. W., & Lieberman, A. F. (2021). Maternal Pregnancy Wantedness and Perceptions of Paternal Pregnancy Wantedness: Associations with Perinatal Mental Health and Relationship Dynamics. Maternal and Child Health Journal, 25(3), 450–459. 10.1007/s10995-020-03084-1
River, L. M., Narayan, A. J., Atzl, V. M., Rivera, L. M., & Lieberman, A. F. (2020). Romantic Partner Support During Pregnancy: The Discrepancy Between Self-Reported and Coder-Rated Support as a Risk Factor for Prenatal Psychopathology and Stress. Journal of Social and Personal Relationships, 37(1), 27–46. https://doi.org/10.1177/0265407519850333
Narayan, A. J., Hagan, M. J., Cohodes, E., Rivera, L. M., & Lieberman, A. F. (2019). Early Childhood Victimization and Physical Intimate Partner Violence During Pregnancy: A Developmental and Person-Oriented Approach. Journal of Interpersonal Violence. https://doi.org/10.1177/0886260516639261
Narayan, A. J., Rivera, L. M., Bernstein, R. E., Harris, W. W., & Lieberman, A. F. (2018). Positive Childhood Experiences Predict Less Psychopathology and Stress in Pregnant Women with Childhood Adversity: A Pilot Study of the Benevolent Childhood Experiences (BCEs) Scale. Child Abuse & Neglect, 78, 19–30. 10.1016/j.chiabu.2017.09.022
Waters, S. F., Hagan, M. J., Rivera, L., & Lieberman, A. F. (2015). Improvements in the Child‐Rearing Attitudes of Latina Mothers Exposed to Interpersonal Trauma Predict Greater Maternal Sensitivity Toward Their 6‐Month‐Old Infants. Journal of Traumatic Stress, 28(5), 426-433. 10.1002/jts.22043
Attachment Vitamins
Waters, S. F., Hulette, A., Davis, M., Bernstein, R., & Lieberman, A. (2020). Evidence for Attachment Vitamins: A Trauma-Informed Universal Prevention Programme for Parents of Young Children. Early Child Development and Care, 190(7), 1109–1114.
Cohodes, E., Chen, S., & Lieberman, A. (2017). Maternal Meta-Emotion Philosophy Moderates Effect of Maternal Symptomatology on Preschoolers Exposed to Domestic Violence. Journal of Child and Family Studies, 26(7), 1831–1843.
Hulette, A. C., Dunham, M., Davis, M., Gortney, J., & Lieberman, A. F. (2016). Early Intervention for Families Exposed to Chronic Stress and Trauma: The Attachment Vitamins Program. Zero to Three, 36(6), 19-25.
Building Bridges / Semillas de Apego
Jaramillo, N., & Bonet de Vivero, M. (2024). Inversión en cuidadores, salud mental y desarrollo infantil: Un análisis costo-beneficio de Semillas de Apego. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.4959453
Aksunger, N., Vernot, C., Littman, R., Voors, M., Meriggi, N. F., Abajobir, A., Beber, B., Dai, K., Egger, D., Islam, A., Kelly, J., Kharel, A., Matabaro, A., Moya, A., Mwachofi, P., Nekesa, C., Ochieng, E., Rahman, T., Scacco, A., & van Dalen, Y. (2023). COVID-19 and mental health in 8 low- and middle-income countries: A prospective cohort study. PLOS Medicine, 20(4), e1004081. https://doi.org/10.1371/journal.pmed.1004081
Harker Roa, A., Córdoba Flechas, N., Moya, A., & Pineros-Leano, M. (2023). Implementing psychosocial support models in contexts of extreme adversity: lessons from a process evaluation in Colombia. Frontiers in Psychology, 14. https://doi.org/10.3389/fpsyg.2023.1134094
Sánchez-Ariza, J., Cuartas, J., and Moya, A. (2023). The Mental Health of Caregivers and Young Children in Conflict-Affected Settings. AEA Papers and Proceedings, 113 : 336–41. https://www.aeaweb.org/articles/pdf/doi/10.1257/pandp.20231017
Moya, A., Serneels, P., Desrosiers, A., Reyes, V., Torres, M. J., & Lieberman, A. (2021). The COVID-19 pandemic and maternal mental health in a fragile and conflict-affected setting in Tumaco, Colombia: a cohort study. The Lancet Global Health, 9(8). https://doi.org/10.1016/s2214-109x(21)00217-5
Moya, A., Torres, M. J., Harker, A., Sánchez, J., Niño, B., Reyes, V., & Lieberman, A. (2021). Maternal Mental Health and Early Childhood Development in Conflict-Affected Settings: Experimental Evidence from Colombia. IFRI. https://amdseminarseries.wordpress.com/wp-content/uploads/2024/01/maternalmentalhealth-and-ecd_feb28_paper.pdf
Trauma and Protective Factors
Impact of Trauma
Chu, A. T., Bond, M. H., Rogowski, B., Leba, N. V., Ghosh Ippen, C., Cirolia, A., & Lieberman, A. F. (2025). Posttraumatic stress in infancy: The roles of cumulative trauma and caregiving context. Infant Mental Health Journal, 1–13. https://doi.org/10.1002/imhj.70015
Ponting, C., Bond, M., Rogowski, B., Chu, A., & Lieberman, A. F. (2024). Childhood and adulthood trauma exposure: Associations with perinatal mental health and psychotherapy response. Journal of traumatic stress, 37(1), 178–186. https://doi.org/10.1002/jts.22989
Ponting, C., Tomlinson, R. C., Chu, A., & Lieberman, A. F. (2024). Mitigating the impact of intimate partner violence in pregnancy and early childhood: A dyadic approach to psychotherapy. Family Court Review, 62(1), 112–130. https://doi.org/10.1111/fcre.12766
Atzl, V.M., Narayan, A.J., Rivera, L.M., Lieberman AF. (2019) Adverse Childhood Experiences and Prenatal Mental Health: Type of ACEs and Age of Maltreatment Onset. Journal of Family Psychology 33(3):304-314.
Narayan, A. J., Hagan, M. J., Cohodes, E., Rivera, L. M., & Lieberman, A. F. (2019). Early Childhood Victimization and Physical Intimate Partner Violence During Pregnancy: A Developmental and Person-Oriented Approach. Journal of Interpersonal Violence, 34(1), 3–26.
Aschbacher, K., Hagan, M. J., Steine, I. M., Rivera, L. M., Cole, S., Baccarella, A., Epel, E. S., Lieberman, A. F., & Bush, N. R. (2021). Adversity in Early Life and Pregnancy are Immunologically Distinct from Total Life Adversity: Macrophage-Associated Phenotypes in Women Exposed to Interpersonal Violence. Translational Psychiatry, 11.
Browne, D. T., May, S., & Lieberman, A. (2020). Traumatic Events and Associated Symptoms Amongst Caregiver-Child Dyads: Exploring Caregiver Sex Differences. Journal of Child and Family Studies, 29(8), 2155–2168.
Cohodes, E. M., Chen, S. H., Lieberman, A. F., & Bush, N. R. (2020). Examination of the Associations Between Young Children’s Trauma Exposure, Trauma-Symptomatology, and Executive Function. Child Abuse & Neglect, 108, 104635.
Chen, S. H., Cohodes, E., Bush, N. R., & Lieberman, A. F. (2020). Child and Caregiver Executive Function in Trauma-Exposed Families: Relations with Children’s Behavioral and Cognitive Functioning. Journal of Experimental Child Psychology, 200, 104946.
Cohodes, E. M., Gee, D. G., & Lieberman, A. F. (2019). Associations Between Prenatal Substance Exposure, Prenatal Violence Victimization, Unintended Pregnancy, and Trauma Exposure in Childhood in a Clinical Setting. Infant Mental Health Journal, 40(6), 786–798.
Cohodes, E. Hagan, M. J., Narayan, A. J., & Lieberman, A. F. (2016). Matched trauma: The Role of Parents’ and Children’s Shared History of Childhood Domestic Violence Exposure in Parents’ Reports of children’s trauma-related symptomatology. Journal of Trauma and Dissociation, 17, 81-96.
Hagan, M. J., Sulik, M. J., & Lieberman, A. F. (2016). Traumatic Life Events and Psychopathology in a High Risk, Ethnically Diverse Sample of Young Children: A Person-Centered Approach. Journal of Abnormal Child Psychology, 44(5), 833–844.
Hagan, M. J., Hulette, A. C., & Lieberman, A. F. (2015). Symptoms of Dissociation in a High-Risk Sample of Young Children Exposed to Interpersonal Trauma: Prevalence, Correlates, and Contributors. Journal of Traumatic Stress, 28(3), 258–261.
Thakar, D., Coffino, B., & Lieberman, A. F. (2013). Maternal Symptomatology and Parent–Child Relationship Functioning in a Diverse Sample of Young Children Exposed to Trauma. Journal of Traumatic Stress, 26(2), 217–224.
Lieberman A. F., Chu, A. T., Van Horn P, Harris W. W. (2011).Trauma in Early Childhood: Empirical Evidence and Clinical Implications. Development and Psychopathology., (2):397-410.
Busch, A. L., & Lieberman, A. F. (2010). Mothers’ Adult Attachment Interview Ratings Predict Preschool Children’s IQ Following Domestic Violence Exposure. Attachment and Human Development, 12(6), 505–527
Chu, A. T., & Lieberman, A. F. (2010). Clinical Implications of Traumatic Stress from Birth to Age Five. Annual Review of Clinical Psychology, 6(1), 469–494.Ybarra, G., Wilkens, S., & Lieberman, A. (2007). The Influence of Domestic Violence on Preschooler Behavior and Functioning. Journal of Family Violence, 22, 33–42.
Johnson, V., & Lieberman, A. (2007). Variations in Behavior Problems of Preschoolers Exposed to Domestic Violence: The Role of Mother’s Attunement to Children’s Emotional Experiences. Journal of Family Violence, 22(5), 297–308.Smith Stover, C., Van Horn, P., & Lieberman, A. F. (2006). Parental Representations in the Play of Preschool Aged Witnesses of Marital Violence. Journal of Family Violence, 21, 417-424.
Lieberman, A. F., Van Horn, P., & Ozer, E. J. (2005). Preschooler Witnesses of Marital Violence: Predictors and Mediators of Child Behavior Problems. Development and Psychopathology, 17(2), 385–396.
Angels in the Nursery
Narayan, A. J., Ippen, C. G., Harris, W. W., & Lieberman, A. F. (2019). Protective Factors That Buffer Against the Intergenerational Transmission of Trauma from Mothers to Young Children: A Replication Study of Angels in the Nursery. Development and Psychopathology, 31(1), 173–187.
Narayan, A. J., Ippen, C. G., Harris, W. W. & Lieberman, A. F. (2017), Assessing Angels in the Nursery: A Pilot Study of Childhood Memories of Benevolent Caregiving As Protective Influences. Infant Mental Health Journal, 38: 461-474.
Lieberman, A. F., Padrón, E., Van Horn, P., & Harris, W. W. (2005). Angels in the Nursery: The Intergenerational Transmission of Benevolent Parental Influences. Infant Mental Health Journal: Official Publication of The World Association for Infant Mental Health, 26(6), 504-520.
Theoretical Reviews
Narayan, A. J., Lieberman, A. F., & Masten, A. S. (2021). Intergenerational Transmission and Prevention of Adverse Childhood Experiences (ACEs). Clinical Psychology Review, 85, 101997.
Zeanah, C. H., & Lieberman, A. (2016). Defining Relational Pathology In Early Childhood: The Diagnostic Classification Of Mental Health And Developmental Disorders of Infancy And Early Childhood Dc:0–5 Approach. Infant Mental Health Journal, 37(5), 509–520.
Zeanah, C. H., Carter, A. S., Cohen, J., Egger, H., Gleason, M. M., Keren, M., Lieberman, A., Mulrooney, K., & Oser, C. (2016). Diagnostic Classification Of Mental Health And Developmental Disorders Of Infancy And Early Childhood Dc:0–5: Selective Reviews From A New Nosology For Early Childhood Psychopathology. Infant Mental Health Journal, 37(5), 471–475.
Lieberman, A., Zeanah, C., & McIntosh, J. (2011). Attachment Perspectives On Domestic Violence And Family Law. Family Court Review, 49(3), 529–538.
Lieberman, A. F. (2011). Infants Remember: War Exposure, Trauma, and Attachment in Young Children and Their Mothers. Journal of the American Academy of Child and Adolescent Psychiatry, 50(7), 640–641.
Osofsky, J. D., & Lieberman, A. F. (2011). A Call for Integrating a Mental Health Perspective Into Systems of Care for Abused and Neglected Infants and Young Children. The American Psychologist, 66(2), 120–128.
Gleason, M. M., Egger, H. L., Emslie, G. J., Greenhill, L. L., Kowatch, R. A., Lieberman, A. F., Luby, J. L., Owens, J., Scahill, L. D., Scheeringa, M. S., Stafford, B., Wise, B., & Zeanah, C. H. (2007). Psychopharmacological Treatment for Very Young Children: Contexts and Guidelines. Journal of the American Academy of Child and Adolescent Psychiatry, 46(12), 1532–1572.
Harris W. W., Lieberman A. F., Marans S. (2007). In the Best Interests of Society. Journal of Child Psychology and Psychiatry 48(3-4):392-411.
Lieberman, A. F., & Knorr, K. (2007). The Impact of Trauma: A Developmental Framework for Infancy and Early Childhood. Pediatric Annals., 36(4), 209–215.
Lieberman A. F. (2003). The Treatment of Attachment Disorder in Infancy and Early Childhood: Reflections From Clinical Intervention with Later-Adopted Foster Care Children. Attachment and Human Development, 5(3), 279–282.