Research figure: Mary Ainsworth · Written by Artificial Sapiens
Patterns of Attachment: A Psychological Study of the Strange Situation is the landmark 1978 monograph by Mary D. Salter Ainsworth, Mary C. Blehar, Everett Waters, and Sally Wall. It established a detailed, observation-based account of how infant–caregiver attachment relationships could be studied through carefully structured episodes of exploration, unfamiliarity, separation, and reunion. Its enduring contribution is methodological as well as conceptual: the authors integrated a year of naturalistic observation with a standardized laboratory procedure, explicit behavioral coding, a three-group classification system, and tests of how laboratory differences related to everyday caregiving. The book remains a foundational primary source for developmental psychology and attachment research. Original edition and preface.
What Is Patterns of Attachment?
The full title is Patterns of Attachment: A Psychological Study of the Strange Situation. First published in 1978 by Lawrence Erlbaum Associates, the volume brings together theoretical argument, research procedures, empirical findings, analyses of earlier studies, and a final interpretation of attachment patterns. The title refers to organized ways infants deploy behavior in relation to a familiar attachment figure when exploration and proximity seeking are brought into tension. The classification refers to the observed relationship with a particular caregiver in a defined developmental and assessment context. It does not designate a permanent personal identity, an inherited temperament category, or a psychiatric diagnosis.
The primary question is how a researcher can identify meaningful individual differences in attachment when virtually all normally developing infants may sometimes cry, cling, explore, avoid proximity, or protest separation. The answer developed in this book is to observe the organization and timing of behaviors across changing conditions. An infant's response to reunion becomes particularly informative when interpreted alongside exploration before separation, distress during separation, and behavior toward an unfamiliar adult. The authors' theory drew on John Bowlby's attachment framework and on Ainsworth's own earlier secure-base observations. Book contents and original preface.
Publication History, Authorship, and the 1978 Date
The original title page credits four scholars: Mary D. Salter Ainsworth, Mary C. Blehar, Everett Waters, and Sally Wall. Their names belong together in the formal bibliographic citation. Ainsworth supplied the long-running observational program and much of the conceptual groundwork; the monograph is a collective scholarly work whose research, analysis, synthesis, and publication must retain the other three authors' contributions. The original edition's copyright and publication statement explicitly gives 1978 and Lawrence Erlbaum Associates. A publisher-hosted preview of a 2014 Psychology Press edition reproduces this information. Facsimile of title and copyright pages.
Some later Routledge product listings describe an edition as first published in 1979 or display a 1979 copyright year. That discrepancy arises in later catalog or edition metadata and does not displace the explicit 1978 original-edition statement. Modern reissues have also appeared under Psychology Press and Routledge, including a classic edition with additional prefatory material. When citing the historical argument or classification program, identify the 1978 original. When quoting or using pagination from a reissue, identify that edition separately. Routledge catalog record.
The 1978 book is distinct from Ainsworth's earlier Infancy in Uganda (1967), Ainsworth and Barbara A. Wittig's 1969 chapter on attachment and exploratory behavior in a strange situation, and the 1970 article coauthored by Ainsworth and Silvia M. Bell. Those works document preceding phases of the program. The book systematizes and interprets a wider research record, incorporating extensive comparison with other investigators' studies. The 1970 Bell paper is independently documented in Child Development and PubMed. Ainsworth and Bell, 1970.
The Intellectual Problem Behind the Book
Bowlby's work positioned attachment within an ethological and developmental framework. Attachment behavior, in that account, serves the protection and regulation of a young child in relation to a familiar caregiver. Ainsworth's contribution made it possible to study the organization of attachment in a concrete relationship through repeated observations. Her intellectual formation also drew on William E. Blatz's security theory; the original book's preface recalls the secure-base idea from her Toronto training. Bowlby formulated the theoretical attachment system, while Ainsworth and her collaborators elaborated the observational and measurement program presented here. Bretherton, 1992.
The researchers faced a measurement problem. In a familiar home, the environment might permit prolonged exploration and offer few occasions that strongly activate attachment behavior. During a laboratory visit, an unfamiliar room, stranger, brief departures, and reunions could produce an organized sequence of behavioral changes. The purpose was to compare how each infant balanced attachment and exploration, rather than simply to count whether an infant cried. The procedure was conceived in 1964 as an adjunct to Baltimore longitudinal observations, following earlier Uganda fieldwork. The original preface identifies 26 Baltimore mother–infant pairs and an earlier Uganda program involving 28 pairs. Original preface.
One insight is especially important. Separation distress by itself cannot establish security. Some infants who have a clear attachment relationship show little overt protest in a particular setting; others become highly distressed but differ in how effectively reunion supports regulation and a return to exploration. The unit of interpretation is the patterned response across episodes and interactions. This is why a relationship-based assessment cannot be substituted with an isolated behavioral checklist.
The Book's Four-Part, Fifteen-Chapter Structure
The monograph is organized into introduction, method, results, and discussion. Chapter 1 supplies theoretical background, distinguishing the attachment system, its observable behaviors, associated emotion, and the development of child–caregiver attachment. Chapters 2 and 3 describe the participants and procedure and then the assessment machinery: percentages, frequencies, interaction ratings, and assignment to attachment groups. These chapters establish the operational bridge from theoretical claim to observable data. Original table of contents.
The results section moves from concrete behavioral description to increasingly demanding evaluation. Chapter 4 examines each of the eight episodes; chapter 5 examines normative trends, including exploration, crying, searching, proximity and contact, avoidance, resistance, and social responses. Chapter 6 tests the classificatory system with multiple discriminant function analysis. Chapter 7 compares laboratory infant behavior with behavior at home, and chapter 8 compares laboratory infant behavior with maternal behavior observed at home. Chapters 9 and 10 review other Strange Situation investigations in younger and older children; chapter 11 examines repetition of the procedure; chapter 12 analyzes the utility of subgroups. Publisher chapter inventory.
The discussion occupies chapters 13–15. The authors first evaluate normative phenomena such as the secure base, reactions to strangers, and separation. They then consider the stability, contextual meaning, and theoretical interpretation of individual differences. The final chapter addresses groups B, C, and A in that sequence. Appendices give procedural and coding material, followed by references and indexes. This architecture makes the volume both an empirical research report and a methodological reference: readers can trace a general theoretical position through observation, measurement, statistical interrogation, and interpretation.
From Uganda and Baltimore Home Visits to Laboratory Measurement
The book cannot be understood as a free-standing laboratory invention. Ainsworth's observations in Uganda identified how infants directed attention, proximity seeking, and exploration toward caregivers. Her Baltimore longitudinal program then collected repeated observations in infants' own homes. These contexts permitted investigation of responsiveness, caregiving routines, and the circumstances in which a child approached, explored away from, or returned to a caregiver. The laboratory procedure was intended to complement those records by making relevant circumstances more comparable across dyads. Original preface.
The two settings provided distinct kinds of evidence. Home observation carried ecological depth and longitudinal information about particular relationships. A structured unfamiliar situation increased control over changes in the child's immediate context. The monograph's chapters 7 and 8 are central because they ask whether laboratory-defined patterns connect with independent observations of daily behavior and caregiving. If a laboratory classification simply described how infants behaved in one room on one day, its developmental interpretation would be narrower. Relating the procedures to another setting was therefore an essential part of the research logic.
The Baltimore participants were a small, socially and geographically concentrated group. A small longitudinal group can sustain intensive observation and hypothesis development, while broader conclusions require evidence from independently recruited samples. That distinction became more important as Strange Situation research spread to additional countries, communities, caregiver arrangements, and developmental circumstances. The 1978 original provides a historically important starting point, not the entire present-day evidence base.
The Strange Situation as Presented in the Book
Why the Episodes Are Organized as a Sequence
The Strange Situation uses a series of brief episodes in an unfamiliar playroom. The infant initially has opportunities to explore in the caregiver's presence. A stranger enters, the caregiver departs and returns, and another separation and reunion follow. The procedure changes the expected accessibility of familiar and unfamiliar adults and varies the immediate opportunities for exploration and comfort. Its design emerged from concrete questions about infant behavior in home and laboratory conditions, not from an arbitrary attempt to produce the most distress possible. Original preface and procedures.
What Observers Actually Code
The measurement system addresses multiple behaviors. Researchers can examine exploration, orientation, proximity and contact seeking, contact maintenance, resistance to contact, avoidance, distress, searching, and communication across episodes. The book describes percentage measures, frequency measures, and ratings of interactive behaviors. The interpretation focuses on sequences, balance, and behavioral organization. A child may show intense distress and still use reunion with the caregiver efficiently to become comforted. Another child may show little overt distress yet actively minimize interaction when the caregiver returns. Similar visible behavior can acquire different significance in its relational and episodic context.
Why Reunion Is Central
Reunion supplies an opportunity to observe what happens when an accessible caregiver reappears after an experimentally controlled separation. The response helps distinguish organized strategies of contact, comfort, avoidance, and resistance. Its importance rests on the interaction between infant behavior and the restored availability of the caregiver. Researchers assess patterned differences rather than score distress alone as a direct index of love, dependence, health, or resilience. The book's later comparison of groups and subgroups includes detailed treatment of greetings and other reunion behaviors. Chapter inventory.
The Original Three Attachment Groups: A, B, and C
Group B: Secure Attachment
Group B generally describes infants whose behavior reflects effective use of the caregiver as a secure base for exploration and a source of comfort following separation. The specific form and intensity of protest vary, while the organization of reunion is especially informative. Security does not mean constant happiness, zero anxiety, or independence from others. It describes a characteristic relationship pattern under the circumstances of the assessment. In the original classification program, group B was the secure category.
Group A: Avoidant Attachment
Group A describes an organized pattern marked by comparatively limited overt proximity seeking or active avoidance of the caregiver at reunion. Some infants may attend to toys or other elements of the situation while reducing visible bids for interaction. Researchers interpret the configuration across episodes, including signs that might be missed by judging crying alone. Avoidance in this classification is an observed infant–caregiver pattern in a particular assessment, not evidence that the child lacks an attachment bond or is incapable of emotion.
Group C: Resistant or Ambivalent Attachment
Group C describes an organized pattern in which strong proximity or contact seeking may be accompanied by resistance, difficulty settling, and constrained return to exploration. The child may pursue the caregiver yet show anger or resistance during interaction. The historical nomenclature includes resistant and ambivalent/resistant descriptions. These are observational terms for behavior in the procedure, not adult personality types. The original monograph also discussed subgroups within the three major classifications.
Why Group D Belongs to Later Research
The later disorganized/disoriented category, commonly designated D, is associated with Mary Main and Judith Solomon's subsequent work. It should not be retrospectively described as one of the classifications introduced by Ainsworth, Blehar, Waters, and Wall in 1978. Research using the extended classification framework can examine disorganization in addition to the organized A/B/C patterns. Scientific histories should identify each development in its own chronological context. Historical account in Duschinsky, 2020.
Statistical and Measurement Ambitions
The monograph's treatment of classification reaches beyond simply naming three groups. Chapter 6 examines the system using multiple discriminant function analysis and reports a cross-validation exercise. Its table of contents specifies the contribution of 22 variables to distinguishing groups. The scientific issue is whether independently measurable behavioral dimensions correspond to the qualitative organizations identified by observers. This gives the classification program an empirical test within the original dataset, although such analyses cannot by themselves establish universal validity. Original contents, chapter 6.
A classification system must also withstand challenges beyond the original observations: coders must follow reproducible rules, agreement across trained observers must be adequate, results must respond intelligibly to developmental changes, and associations with external measures must be investigated. Training and consistent coding help make complex observation more reliable. Even strong within-sample discrimination does not substitute for replication with different participants, cultural circumstances, caregivers, and independently trained teams.
The authors' attention to repeated administrations and to subgroups matters here. A method that itself exposes participants to unfamiliarity and separation might yield different behavior if a child has already experienced the room or the assessment. Developmental age can also change the meaning of separation, stranger response, and exploration. Chapters on repetition and older children document that the authors considered these measurement questions within the research program.
Home Behavior, Caregiver Sensitivity, and the Interpretation of the Groups
The book relates laboratory groupings to observations of the infant and caregiver in the home. Ainsworth's work on sensitivity treated caregiving as the capacity to notice, interpret, and respond appropriately to the infant's signals. Her original scales used historical terminology concerning maternal behavior because the Baltimore home program studied mother–infant dyads. Contemporary attachment research also investigates fathers, other caregivers, and diverse family structures. The historical sample description must remain intact while current scientific interpretation reflects a broader set of caregiver relationships.
The conceptual claim is that the availability and responsiveness of a caregiver can become relevant to how an infant organizes expectations and behavior in that relationship. The empirical claim is more specific: observational indices of sensitivity and attachment security should be associated across samples. Modern meta-analysis finds a statistically reliable, moderate-to-small pooled correlation rather than perfect correspondence. In 2024, Madigan and colleagues combined 174 samples and 22,914 caregiver–child dyads and reported r = .25, 95% confidence interval [.22, .28], for the overall sensitivity–security relationship. The study also found positive associations for maternal and paternal sensitivity. These findings support the importance of caregiving while leaving room for temperament, context, measurement, developmental timing, and other influences. Madigan et al., 2024.
Correlation is not a license to infer that any one infant's classification was caused by a single caregiver action. The original naturalistic records are valuable for temporal and behavioral context; they are not randomized causal experiments. Later randomized interventions provide a different evidentiary perspective. A Cochrane review found moderate-certainty evidence that video feedback improved observed parental sensitivity, with substantially lower certainty for child attachment outcomes and insufficient evidence for several other proposed benefits. This difference between measurable caregiving change and demonstrated changes in attachment classification is important when translating the 1978 program into practice. Cochrane review.
What the 1978 Book Established and What Later Work Tested
The established historical contribution is a coherent research program. The authors described standardized observation, a classification framework, links to longitudinal home behavior, and procedures for testing the interpretability of classifications. They also reviewed research available at the time. These features gave later investigators a common method and vocabulary with which to compare studies. A measurement tradition emerged because the book specified what to observe and why the pattern mattered, creating a foundation for replication and disagreement alike.
Large contemporary datasets clarify what the original sample could not settle. A 2023 meta-analytic review synthesized more than 285 Strange Situation studies involving 20,720 caregiver–infant dyads. It examined distributions of classifications, temporal patterns, geographic variation, and population differences. The existence of this international body of evidence confirms the procedure's extraordinary methodological reach; the documented variation also shows why the Baltimore distributions should not be treated as fixed percentages for every society or caregiving setting. Madigan et al., 2023.
Evidence for sensitivity is established at the level of aggregate association, with effect sizes depending on how observation is conducted. The 2024 synthesis reports variation by instrument, observation length, reliability, and timing. That result is scientifically informative because it connects the foundational attachment hypothesis with contemporary measurement quality. It also corrects simplistic accounts in which security follows automatically from an idealized parenting style or a single interaction. Madigan et al., 2024.
Predictive research must likewise be interpreted probabilistically. Attachment patterns have been studied in relation to later social, emotional, and developmental outcomes, but associations are neither immutable pathways nor individual clinical forecasts. Family ecology, changing relationships, and later experiences can modify developmental trajectories. The original book helps frame prospective hypotheses; longitudinal and meta-analytic research must determine whether particular predictions survive broader tests.
Cross-Cultural Interpretation and Scientific Debate
The book emerged from observation in Uganda and Baltimore, already suggesting that expressions of security and responses to unfamiliarity could vary with experience and social organization. Subsequent cross-cultural research has challenged investigators to distinguish a proposed attachment system from local expectations about separations, strangers, communal care, and socially encouraged exploration. A classic meta-analysis by van IJzendoorn and Kroonenberg in 1988 compared cross-cultural distributions of Strange Situation classifications. Later multinational synthesis greatly expanded the scale of evidence. Van IJzendoorn and Kroonenberg, 1988; Madigan et al., 2023.
A cultural difference in observed classifications can arise from multiple mechanisms: variation in caregiving ecology, the customary frequency of separations, the unfamiliarity of the laboratory, the distribution of stressors, differences in recruited samples, and differences in how behavior is assessed. The observation that security-related processes may matter across populations does not imply that every local distribution should resemble the original Baltimore sample. The appropriate question is how adequately the specific procedure and interpretation capture relationship organization in the population studied.
The 1978 book also uses maternal language consistent with its historical cohort. A modern scientific reading preserves that historical information while considering multiple attachment figures and gender-inclusive caregiving research. The original primary source should not be rewritten to fit present terminology; the contemporary evaluation should distinguish its design from the wider phenomena to which researchers now apply attachment concepts.
Temperament, Context, and Competing Explanations
One persistent debate concerns how much behavior in a brief separation setting reflects attachment relationship history, and how much reflects the infant's temperament, immediate state, familiarity with strangers, or context. The monograph does not make every observed response exclusive to attachment; its own organization recognizes interacting behavioral systems. Fearfulness, fatigue, prior separations, and novelty can affect an infant's conduct. The core research strategy is to interpret multiple behaviors in relation to changing caregiver accessibility, supplemented where possible by other observations.
Temperamental variation may influence intensity without determining the relational organization of the response. Yet methodological safeguards remain necessary: investigators must avoid circular interpretation, in which a child is labeled insecure because of a behavior and that same label is then used as the sole explanation of the behavior. Additional home observations, coder agreement, pre-specified rules, and independent predictions provide stronger tests. Duschinsky's historical synthesis places these debates in the evolving practices of attachment laboratories rather than a single unchanging doctrine. Duschinsky, 2020.
Scientific Influence and Later Extensions
Patterns of Attachment shaped developmental science by offering a vocabulary for attachment organization, an observational procedure capable of widespread reproduction, and a research agenda connecting everyday relationships to controlled assessment. It became central to work on caregiver responsiveness, infant emotion regulation, secure-base exploration, risk and resilience, and the measurement of early relationships. Its classifications provided a reference point from which later researchers could refine coding and investigate new populations. The 2015 classic reissue testifies to its standing as a text investigators continue to examine. Publisher record.
The later disorganization classification associated with Main and Solomon, continuous measures such as the Attachment Q-Sort, investigations of adult representations, and studies of romantic attachment enlarged the research field. These developments need their own methodological and historical attribution. Adult romantic attachment measures, often organized around anxiety and avoidance, are not direct adult versions of the infant A/B/C laboratory categories. The foundational book supplies historical roots for some questions about relational expectations, but its empirical observations concerned infants in specific caregiver relationships.
Clinical practice draws from attachment research while operating under different standards of inference. A Strange Situation classification is a specialized research assessment of relationship behavior; it is not a diagnosis of reactive attachment disorder, disinhibited social engagement disorder, autism, trauma, or a personality disorder. No single classification demonstrates mistreatment or provides a deterministic forecast. Clinical concerns require comprehensive evaluation of the individual child, caregivers, development, environment, and presenting symptoms. This distinction preserves the book's actual scientific contribution and protects against misuse of its categories.
A Critical Assessment of the Book as a Historical Research Source
The primary strengths of the monograph are its operational transparency, integration of home and laboratory observation, substantive treatment of competing behaviors, explicit examination of classifications, and willingness to examine cross-study comparisons and methodological weaknesses. Its research logic demonstrates why close observation of relationships can produce testable scientific questions. The chapter-level progression from procedure to analysis to qualified interpretation is one reason the book remains valuable for understanding how developmental constructs are built.
Its limits follow from the original sample, circumstances, and historical scientific context. The Baltimore longitudinal group was small and concentrated; the laboratory imposed a particular sequence of separations and reunions; mother–infant relations were the principal focus; and contemporary cross-cultural, father–infant, and diverse-caregiver databases were not yet available. The book's original analyses can establish the internal logic and historical evidence for the proposed categories, but later replication, meta-analysis, and conceptual critique are needed for general claims. The publication's significance is fully compatible with reassessing its assumptions.
A careful reader distinguishes three levels of statement. Established historical facts include the four authors, 1978 original publication, chapter structure, and documented procedures. Established contemporary empirical evidence includes broad replication of the Strange Situation and the pooled positive association of caregiver sensitivity with security. Limited or contested propositions include universal cultural interpretations, strong causal accounts inferred from observation alone, and sweeping predictions about adult character based on one infant assessment. Scientific precision depends on keeping these levels visible.
Questions Readers Commonly Ask
Was Patterns of Attachment written by Mary Ainsworth alone?
No. The 1978 monograph names Mary D. Salter Ainsworth, Mary C. Blehar, Everett Waters, and Sally Wall as its four authors. A citation that drops Blehar, Waters, or Wall gives an incomplete bibliographic history. Original title page.
Was the book first published in 1978 or 1979?
The original-edition statement gives 1978 and Lawrence Erlbaum Associates. Some later catalogs display 1979, but the reproduced first-publication page establishes the original year. Later reprints and editions should be cited with their own dates where relevant.
Is Patterns of Attachment the same as the Strange Situation Procedure?
The procedure is one method described and analyzed by the book. The monograph is a much larger scientific work incorporating theory, coding rules, empirical results, comparisons with naturalistic home observations, published research reviews, statistical analysis, and theoretical discussion. It also provides the historical context of the A/B/C classification program.
Did the book introduce disorganized attachment?
The book's foundational system comprises the original A, B, and C groups. The later disorganized/disoriented D category belongs to the subsequent work of Mary Main and Judith Solomon. These developments form one research history with distinct authorship and chronology.
Can a parent use the book to classify their own child?
Scientific attachment classification requires standardized observation and trained interpretation of behavioral sequences in a particular caregiver relationship. Everyday separation distress, apparent independence, clinginess, or affection by itself is insufficient for classification. The procedure does not diagnose mental illness or assign a lifelong personality label.
Why do scholars still study a book from 1978?
It provides the founding methodological exposition for a major research tradition. Modern studies can test its constructs in much larger and more diverse samples, refine its methods, or challenge its interpretations. A historical landmark remains scientifically useful when its primary claims are assessed against subsequent evidence rather than accepted as final conclusions.
Related Articles
Mary Ainsworth — The researcher's intellectual development, Uganda and Baltimore programs, methods, collaborators, and broader scientific legacy.
John Bowlby — The attachment-theoretical foundation that supplied the central explanatory framework for Ainsworth's observational investigations.
John Bowlby's Attachment Theory: Origins, Principles, and Legacy — The development of attachment theory as a conceptual program, distinct from the 1978 book's methodological and empirical analysis.
Attachment in Infancy and Early Childhood: Security and Development — Contemporary developmental and relationship-based context for infant attachment.
Adult Attachment Theory: How Anxiety and Avoidance Shape Relationships — A later, conceptually related research tradition whose measures and constructs differ from the infant Strange Situation.
Mary Ainsworth's Strange Situation Procedure: Design, Episodes, and Interpretation
Mary Ainsworth's Baltimore Longitudinal Study: Methods and Discoveries
Mary Ainsworth's Attachment Classifications: Secure, Avoidant, and Resistant
References
Ainsworth, M. D. S., and Bell, S. M. (1970). Attachment, exploration, and separation: Illustrated by the behavior of one-year-olds in a strange situation. Child Development, 41(1), 49–67. https://doi.org/10.2307/1127388.
Ainsworth, M. D. S., Blehar, M. C., Waters, E., and Wall, S. (1978). Patterns of attachment: A psychological study of the Strange Situation. Lawrence Erlbaum Associates. Original book facsimile. Digital edition DOI.
Bretherton, I. (1992). The origins of attachment theory: John Bowlby and Mary Ainsworth. Developmental Psychology, 28(5), 759–775. https://doi.org/10.1037/0012-1649.28.5.759.
Duschinsky, R. (2020). Cornerstones of attachment research. Oxford University Press. https://doi.org/10.1093/med-psych/9780198842064.001.0001.
Madigan, S., Deneault, A.-A., Duschinsky, R., Bakermans-Kranenburg, M. J., Schuengel, C., van IJzendoorn, M. H., Ly, A., Fearon, R. M. P., Eirich, R., and Verhage, M. L. (2024). Maternal and paternal sensitivity: Key determinants of child attachment security examined through meta-analysis. Psychological Bulletin, 150(7), 839–872. https://doi.org/10.1037/bul0000433.
Madigan, S., Fearon, R. M. P., van IJzendoorn, M. H., Duschinsky, R., Schuengel, C., Bakermans-Kranenburg, M. J., Ly, A., Cooke, J. E., Deneault, A.-A., Oosterman, M., and Verhage, M. L. (2023). The first 20,000 Strange Situation procedures: A meta-analytic review. Psychological Bulletin, 149(1–2), 99–132. https://doi.org/10.1037/bul0000388.
O'Hara, L., Smith, E. R., Barlow, J., Livingstone, N., Herath, N. I. N. S., Wei, Y., Spreckelsen, T. F., and Macdonald, G. (2019). Video feedback for parental sensitivity and attachment security in children under five years. Cochrane Database of Systematic Reviews. https://pubmed.ncbi.nlm.nih.gov/31782528/.
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van IJzendoorn, M. H., Schuengel, C., Wang, Q., and Bakermans-Kranenburg, M. J. (2023). Improving parenting, child attachment, and externalizing behaviors: Meta-analysis of the first 25 randomized controlled trials on the effects of Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline. Development and Psychopathology, 35(1), 241–256. https://doi.org/10.1017/S0954579421001462.