Abstract
Keywords
Introduction
John Bowlby (1907-1990), the originator of attachment theory, proposed that children look to retain the availability of their caregivers for protection and comfort, and will seek this availability especially when alarmed. He termed this the
The current study seeks to summarize the state of the literature on empirical studies using observational measures of child-parent attachment via a bibliometric analysis using the Child Attachment Studies Catalog and Data Exchange (CASCADE; Madigan, 2020)—a repository of all empirical studies using observational measures of child-parent attachment. Struck et al. (2021, p. 2) noted that “bibliometric methods have been used to quantitatively analyze a large body of peer-reviewed academic literature to indicate time-period productivity, quality, and trends.” Bibliometric analyses offer insight into the scope, diversity, and vitality of a field of research by revealing publication trends and characteristics, as well as allowing researchers to make predictions of growth trajectories over time (Struck et al., 2021). Bibliometric analyses are gaining popularity given their effectiveness in evaluating the advancement of knowledge in a given field (e.g., Asmundson & Asmundson, 2018; Boschen, 2008; Dugas et al., 2010; Elaheh et al., 2018; Ron Norton et al., 1995).
For the attachment field, a recent bibliometric analysis was conducted specifically on meta-analytic studies of attachment across the lifespan. This analysis revealed a rapid increase in the number of meta-analyses and a growing impact of this work on interventions and mental health, as well as a declining impact on work related to attachment relationships and representations (Schuengel et al., 2021). However, bibliometric research on meta-analyses give an incomplete picture of the historical trends in research. Bibliometric research on the primary studies is needed to chart historical trends more fully and identify areas that may urgently call for further research. No bibliometric analyses to date have been conducted on primary studies of infant attachment, limiting our knowledge of the more global body of literature on observational attachment.
Using bibliometric methods, the purpose of this study is to take stock of the empirical research on child-caregiver attachment that has amassed over the last 50 years to assess historical trends and the characteristics of studies within this literature. This study addresses the following research questions: (1) What has been the number of publications in child-caregiver attachment annually from 1970 to 2023 and in which publication venues has this work tended to be published? (2) What are the key characteristics of publications addressing child-caregiver attachment using observational measures per year over the last five decades (e.g., parent gender, geography, population samples, and measurement tools)? (3) What have been the predominant predictors and outcomes of child attachment studied in this body of research?
Observational Measures of Child-Parent Attachment
First introduced by Ainsworth and Wittig in 1969, the Strange Situation Procedure (SSP) pioneered the use of structured, standardized observational assessments of the quality of attachment relationships. The standardized 21-min observational procedure conducted within a laboratory environment involves two episodes of separation and reunion between a child and their caregiver. The procedure simulates a context of stress by evoking what Bowlby (1969) termed natural cues for danger: an unfamiliar environment, the presence of a stranger, and separation from a caregiver. In doing so, the SSP evokes behavior reflecting the child’s expectations about their caregiver’s availability. Based on their behavioral response to the separation-reunion episodes, infants are assigned a classification of secure, avoidant, resistant (Ainsworth et al., 1978), or disorganized (Main & Solomon, 1990).
Infants in
These categories have been empirically associated with various theoretically-expectable correlates, including the caregiver’s behavior toward the child in naturalistic settings, and the child’s later mental health and social adaptation (Groh et al., 2017). Though the categories remain the predominant approach in the literature, an alternative way to measuring individual differences in the SSP has been to code children’s behavior dimensionally (Raby et al., 2021). The continued use of the SSP as an observational measure of attachment over the last 50 years reflects its predictive power (Deneault et al., 2021; Deneault, Duschinsky, Van IJzendoorn, et al., 2023; Deneault, Hammond, & Madigan, 2023; Fearon et al., 2010; Groh et al., 2017; Madigan et al., 2013), as well as the capacity of the measure to yield replication and comparisons across time and context (Madigan, Fearon et al., 2023).
Several adaptations to the SSP have been developed for use in the home, and with older children. The most widely used adaptations are those of preschool and early childhood attachment, namely the Preschool Attachment Classification System (PACS; Cassidy & Marvin, 1992) and the Main-Cassidy 6-year-old system (Main & Cassidy, 1988). These systems code children’s behaviors during a modified SSP; modifications vary across studies, such as the absence of a stranger and longer separations and reunions (Deneault, Bureau, Duschinsky, Fearon, & Madigan, 2023). Analogous classifications of child-caregiver relationships are derived from these observations (secure, avoidant, resistant and disorganized). Another coding system for the preschool years is the Preschool Assessment of Attachment (PAA; Crittenden, 1992), which is likewise based on the SSP.
However, the role of the SSP in the study of attachment has been challenged by attachment researchers and by critics and commentators (Keller, 2021; Lamb et al., 1985). Questions have been raised, for instance, about whether the meaning of the assessment is the same for children who have experienced daycare. This question has been generally put to rest, as the correlates of the SSP appear to be the same for children with and without experience of daycare (Rutter, 2008). However, another question relates to a decline in the prevalence in avoidance over the years. It could be that this represents changes in parenting behavior, or it could represent coder drift (Madigan, Fearon et al., 2023). It should also be noted that, whilst offering one window into children’s expectations about their caregiver’s availability, there has been growing acknowledgment that the SSP does not capture all relevant aspects of the attachment relationship (Schmidt et al., 2021; Ziv & Hotam, 2015). For instance, whereas the SSP focused on children’s response to reunion with their caregivers, other measures have been developed that examine children’s expectations of caregiver support.
Cross-cultural studies using the SSP have also provided insight on the applicability of the instrument in various cultural contexts (Rothbaum & Morelli, 2005). Umemura et al. (2024) recently presented findings from a study that compared three East Asian samples (one Korean and two Japanese) with two Western samples (one U.S.A. and one Czech). They found that the East Asian samples found the pre-separation episodes more distressing than the Western samples, but did not cry more in the reunion episodes. Umemura and colleagues suggest that the SSP may be more valid when used after 18 months in East Asian samples, when children will have more experience of brief separations. They suggest that this cross-cultural difference may impact the distribution of SSP classifications, reducing the validity of the assessment, but not eliminating it: they do not regard the SSP as inappropriate in an East Asian context, but expect more noise and less signal regarding children’s expectations of secure base and safe haven availability in children under 18 months.
Another widely-used observational measure in naturalistic and lab settings is the Attachment Q-Sort (AQS; Waters & Deane, 1985) and its shortened version, the Toddler Attachment Q-Sort (TAS; Andreassen & Fletcher, 2007). The AQS was developed mostly upon Ainsworth’s scoring instructions for home observation and also somewhat the scoring instructions for the SSP (Vaughn et al., 2021). The AQS can be used with children aged 12 to 48 months and is usually based on longer periods of observation (i.e., 1–3 hr). Coders sort a number of cards (90 cards in the original AQS) into different piles based on whether the statement on the card is “not descriptive at all” to “totally descriptive” of the child’s attachment behavior. The sort is then used to derive a correlation of how similar this sort is to a prototypically secure sort, providing a score ranging from −1.0 (very insecure) to 1.0 (very secure). A modified version of the AQS asks caregivers, instead of coders, to conduct the sort. Although the caregiver reported version shows weaker concordance with the SSP (Cadman et al., 2018), it is often used given its scalability.
Predictors and Sequelae of Child-Parent Attachment
Researchers have investigated a number of potential factors that may affect the formation of a secure versus insecure attachment in children to their parents. Meta-analyses have been conducted, for example, on parental influences such as the associations between maternal psychopathology and quality of attachment (Atkinson et al., 2000; Barnes & Theule, 2019; van IJzendoorn et al., 1992) and the associations between parental sensitivity and child attachment (Deneault et al., 2022; Madigan, Deneault, Duschinsky, Bakermans-Kranenburg, Schuengel et al., 2024). Other meta-analyses have examined the associations between child characteristics and the development of child-parent attachment relationships such as children’s language development (van IJzendoorn et al., 1995), children’s history of maltreatment (Baer & Martinez, 2006; Cyr et al., 2010), and children’s emotion understanding (Cooke et al., 2016). There have also been meta-analyses on children’s socioemotional development (Groh et al., 2017), cognitive development (Deneault et al. 2023), behavior problems (Deneault et al., 2021; Fearon et al., 2010; Madigan et al., 2013), peer relations (Pallini et al., 2014; Schneider et al., 2001), and the development of mental health conditions such as depression (Spruit et al., 2020). Other notable meta-analyses have examined cross-cultural differences in attachment formation (van IJzendoorn & Kroonenberg, 1988), family environments such as children’s exposure to intimate partner violence (Noonan & Pilkington, 2020), and attachment patterns in institutionalized, foster, or adopted children (Lionetti et al., 2015; van Den Dries et al., 2009; Vasileva & Petermann, 2018).
Researchers are paying increased attention to how sociodemographic contexts and risk factors affect the development of secure attachment relationships. Socioeconomic risks such as low income, low education, single or adolescent parenthood, and community violence have received considerable attention in the literature (Cyr et al., 2010; Lyons-Ruth et al., 1999; Madigan, Fearon et al., 2023; Main & Hesse, 1990; van IJzendoorn et al., 1992; Verhage et al., 2020). In particular, the disorganized/disoriented attachment classification has provided significant insight into infant-caregiver attachment relationships in high-risk contexts (Duschinsky, 2018; Fearon et al., 2010; Lyons-Ruth et al., 1999; Madigan et al., 2006, 2023; Main & Hesse, 1990; Moss et al., 1999; Out et al., 2009). Thus, it is now well-established in the field of child development that the quality of the child-parent relationship provides insight into how children expect and respond to caregivers’ availability in various contexts of risk and that the child-caregiver attachment relationship is foundational for the health and development of children (Groh et al., 2017).
Researchers have also grappled with whether variables such as child age, sex, and ethnic minority status play a role in attachment formation (Bakermans-Kranenburg & van IJzendoorn, 2009; Del Giudice & Belsky, 2010; Madigan, Deneault et al., 2024; Madigan, Fearon et al., 2023; Waters & Deane, 1985). As researchers have shed light on how sociodemographic risks predict patterns of insecure and disorganized attachment among children, empirical studies on risk factors continue to grow in the literature, with investigations ranging from the effects of child maltreatment (Savage et al., 2019; van IJzendoorn et al., 1999) to parental substance use (Bernard et al., 2018; Connell & Goodman, 2002; Goodman et al., 2011; Hobson et al., 2005; Wan & Green, 2009), and child medical and neurodevelopmental risks (Koren-Karie et al., 2009; van IJzendoorn et al., 2007).
Attachment researchers have also urged for more attention to be paid to investigations of comparisons of child attachment relationships with multiple caregivers such as those between mother-child and father-child or children in institutionalized settings (Dagan et al., 2021; Deneault et al., 2021; Dozier & Rutter, 2016; Fox et al., 1991; Howes & Spieker, 2008; Lamb, 1977; Madigan et al., 2011; Smyke et al., 2012; Steele & Steele, 2017; van Den Dries et al., 2009). Lastly, attachment researchers have also examined the temporal and geographical trends of attachment patterns such as the stability of attachment in children over time and cross-cultural differences in attachment formation (Cabrera et al., 2000; Grossmann & Grossmann, 1989; Kondo-Ikemura et al., 2018; Madigan, Fearon et al., 2023; Takahashi, 1986; van IJzendoorn & Kroonenberg, 1988). Together, this body of research has provided valuable insight into various contexts of risk that shape child-parent attachment, which in turn plays an important role in child development more broadly.
In sum, using bibliometric analysis, the current study will examine historical trends and the characteristics of empirical studies in the area of observational child-caregiver attachment research.
Methods
Our team developed the Child Attachment Studies Catalog and Data Exchange (CASCADE; Madigan, 2020) project, a comprehensive database of empirical studies that used observational measures of child-parent attachment (i.e., SSP, AQS, modified-SSP). CASCADE serves as a comprehensive database that contains information relevant for researchers interested in synthesizing research on observational child-parent attachment, such as attachment distributions in different populations and the variables assessed in various studies. Data from all relevant empirical studies have been extracted and cataloged.
Search Strategy
The current study was conducted following the recommendations and standards set by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA; Moher et al., 2009). A science librarian conducted searches in PsycINFO, MEDLINE, EMBASE, Web of Science, and Dissertation Abstracts International for published and unpublished studies from 1967 to February 16, 2023. Database-specific headings and text word fields were searched for concepts of “strange situation” and “attachment,” with truncation symbols used to capture variant endings and spellings (e.g., infant*). Synonymous terms were combined with the Boolean “OR,” and the concepts were combined with the Boolean “AND.” No language or publication restrictions were applied. A total of 46,776 non-duplicate abstracts were identified across the various databases (see PRISMA flow diagram in Figure 1).

PRISMA flow diagram.
Inclusion and Exclusion Criteria
A team of 10 research personnel (Research Assistants, Research Associate, Post-doctoral Fellow, and student volunteers) independently screened the studies for the following inclusion criteria: (1) child-parent attachment was assessed using an observational measure in infancy, preschool, or middle childhood; (2) the attachment assessment was conducted with fathers, mothers, adoptive/foster caregivers, and/or teacher/professional caregiver; and the study (3) was written in English, French, or Spanish (languages spoken by our team); and (4) published between 1970 and 2023. All studies were double screened to increase reliability of results. Exclusion criteria were: (1) attachment was assessed using representational, questionnaire, or interview-based measures of attachment; and (2) child attachment was assessed with grandparents, other extended family members (aunts, uncles), and/or siblings. In the event that titles and abstracts were insufficient to determine meeting or excluding eligibility criteria, full texts were retrieved.
Data Extraction
A standard coding form was developed by the research team to extract data from each study on measurement characteristics, as well as study-level and sample-level moderators. One coder extracted all study characteristics, attachment distribution data, and potential moderator variables from the studies meeting inclusion criteria. A second independent coder performed data extraction on 22% of randomly selected studies to determine inter-rater reliability. Percent agreement for categorical moderators was 93% (kappa = 0.77). The agreement for continuous moderators was ICC = 0.90, and agreement on the extraction of SSP distributions was 99%. Discrepancies were resolved by review and discussion, and consensus coding was used in data analysis.
Categorical moderators (such as parent gender, SES, etc.) were determined based on 80% or more of the sample falling in a given category. If the information for any given moderator was missing, it was coded as “not specified” unless indicated below. Three general categories of moderators were examined: general study characteristics, temporal trends, and regional factors.
Results
The literature search identified 2,318 publications (peer-reviewed articles, dissertations, book chapters) on child-parent attachment between the years 1970 and 2023. The distribution of studies by year of publication is presented in Figure 2. One-third (30.9%) of all publications have occurred in the last decade, and well over half (64.3%) have been published since the year 2000. For dissertations, the period between 1990 and 2000 saw the sharpest increase, representing 30.7% of all dissertations published on the topic. Since 2000, over half (56.6%) of the dissertations were published in this period. However, there is a notable declining trend in dissertations since the sharp rise in the period between 1990 and 2000.

Number of studies conducted per year (1970–2023).
Among peer-reviewed publications, studies were published in 283 different academic journals. Among the top 10 journals (Figure 3) in which the publications appeared, the majority of the journals are devoted to child development research broadly, attachment research specifically, child mental health, family psychology, psychobiology, and behavioral science.

Top 10 journals for child-parent attachment publications.
Representation of Mothers and Fathers
We found that 88.3% of studies examined child-mother attachment relationships only, with only 9.1% of studies examining both child-mother and child-father attachment, and 1.4% focused solely on child-father attachment. The proportion of studies that have examined child-mother versus child-mother and child-father versus child-father attachment has remained strikingly consistent over the years (Figure 4).

Proportion of attachment studies conducted with mothers only, mothers and fathers, and fathers only per year.
Geographical Representation
As for geographical trends, almost three-quarters (72.8%) of the studies were conducted in North America, and a fifth (18.9%) were conducted in Europe. The remaining 7.4% of studies were conducted in Africa, Asia, Australia, the Middle East, or South America. Figure 5 shows the distribution of studies by geography as viewed on a world map. A total of 48 countries are represented.

World map of distribution of child-parent attachment studies.
Sample Characteristics
Community samples make up almost two-thirds (61.5%) of all the samples in the empirical literature on child attachment. Samples with an indicator of demographic or health risk represent one-quarter (24.7%) of the total number of studies, and clinical and foster/adoptive samples represent 8.3% and 4.4%, respectively.
The majority of samples are drawn from mid-high (36.3%) or mixed (24.7%) socioeconomic background populations, with 17.6% of samples drawn from low socioeconomic settings. A considerable number of studies (21.4%), however, did not specify the socioeconomic status of their study sample.
Of the total number of studies included in this bibliometric analysis of empirical studies, 30.5% of studies did not provide information on ethnicity. Of the studies that did provide information on ethnic composition of their sample, 58.9% were conducted on samples with ≥80% of individuals with non-ethnic minority status. Only 8.2% of studies with information on ethnicity were conducted with samples that had ≥80% of individuals from an ethnic minority background. Across the studies with information on ethnicity status, the average percentage of ethnic minority status represented in the studies is 24.4%.
Measurement Tools
The majority of studies (55.2%) used the Strange Situation Procedure (SSP) as their observational measure of child-parent attachment, with 23% using the Attachment Q-Sort (AQS) or the Toddler Attachment Q-Sort (TAS), and 12.9% reporting results from a SSP measure modified for use with older children (i.e., PACS, Main-Cassidy, and the PAA). The remainder of studies (8.9%) used a combination of instruments such as the SSP and AQS or AQS and PAA.
Predictor and Outcome Variables
The five most frequent
The 10 most prevalent
Descriptions of Predictor Variables.
The five most prevalent
Descriptions of Main Outcome Categories.
Discussion
Attachment theory is one of the most influential theories in developmental science (Dixon, 2015) and has generated thousands of studies. In an effort to take stock of past research, we conducted a bibliometric analysis of empirical studies (i.e., journal articles, chapters, dissertations) using observational measures of attachment between 1970 and 2023. Below we provide a discussion of key findings from the bibliometric analysis and pinpoint areas of growth for future research. While findings of attachment research can be interpreted in various ways depending on cross-cultural and epistemic understandings of security and disorganization (Duschinsky et al., 2021; Wright et al., 2025), this study’s findings nonetheless reveal the historical trends in child-parent attachment research that has resulted in a disproportionate focus on maternal caregivers, Western contexts, and middle-class and non-minority status community samples. The findings also reveal that more research is needed to better understand the parental factors or environmental risks that affect the development of child-parent attachment relationships. These findings can indeed help researchers to see more clearly the research gaps and to design more studies that attempt to address these gaps.
Gender Representation
The vast majority of observational child-parent attachment research over the past 50 years has been and continues to be conducted on child-mother dyads (88.3%). Previous estimations suggested that only 10% of attachment research included fathers (Cowan & Cowan, 2019). Our bibliometric analysis confirmed and extended this estimate within the wider literature. Furthermore, our study found that this percentage has remained relatively constant over the years. Specifically, while there was a peak of research on fathers in the 1980s, it was not sustained over time. There are a few possible explanations for this finding. First, at least initially, the effects of father-child attachment may have generated weaker predictions to child outcomes, and there may have been a general interest among researchers at that time to focus on larger effect sizes. It should be noted that recent meta-analyses have not demonstrated differences in the distribution of attachment among mothers and fathers (Madigan, Fearon et al., 2023), nor the prediction of maternal or paternal caregiver sensitivity on child attachment (Madigan, Deneault et al., 2024), or the predictive capacity of mother-child versus father-child attachment on child outcomes (Dagan et al., 2021; Deneault et al., 2021). Second, it has been acknowledged that many challenges exist to recruiting fathers in research studies, and this may dissuade researchers from conducting such studies (Mitchell et al., 2007). It should be noted, that among the existing research on fathers, the large majority of samples are drawn from homogeneous populations—biparental fathers in a heterosexual relationship from low-risk backgrounds in a Western country. Thus, not only is it essential that we more deliberately and consistently study child-father dyads, but it is also imperative to diversify the fathers studied.
The focus on maternal influences can likely be attributed, in part, to early sociological trends and rearing practices at the time that attachment theory originated. When Bowlby and Ainsworth were developing and refining attachment theory and observational measures of attachment over 50 years ago, mothers were generally the primary caregiver for young children whereas fathers were the primary breadwinners. The development of observational attachment measures on mothers specifically may have influenced research trends. Contemporary sociological data, however, now show that fathers play a much larger role in child-rearing (Sayer, 2018), with a three- to six-fold increase in time spent on child care over the previous generation of fathers (Bakermans-Kranenburg et al., 2019). Moreover, child-father attachment relationships hold comparable associations to mothers on children’s outcomes (Dagan et al., 2021; Deneault et al., 2021). This bibliometric analysis rejoins with past calls to the attachment community to shift and adjust their focus to investigating both mothers
The recent creation of the Society for Emotions and Attachment Studies’ Special Research Interest Group on Father-Child Attachment and Relationships is an encouraging development. Another important research initiative is the series of individual participant data reviews published by Dagan et al. (2021), Dagan, Schuengel, Verhage, Madigan, Roisman, Bernard, et al. (2024), Dagan, Schuengel, Verhage, Madigan, Roisman, Van IJzendoorn, et al. (2024) addressing the interactive effects of mothers and fathers on child attachment and developmental outcomes. This work is based on the expectation that attachment relationships with multiple caregivers (e.g., fathers, mothers) can contribute to positive child development (Dagan & Sagi-Schwartz, 2021). They have found that children who are classified as being in secure relationships with fathers and mothers show fewer behavioral problems, compared to children secure with just one, or no secure attachment. Taking a family systems perspective (Cowan & Cowan, 2019) and considering cross-cultural family configurations that may place more emphasis on the role of extended family members in child-rearing (e.g., Liang et al., 2021) is another critical way for attachment research to be a more diverse and inclusive science.
Geographical Representation
This study revealed that an overwhelming majority (91.7%) of child-parent attachment studies using observational measures have been conducted in North America (72.8%) and Europe (18.9%). This disproportionate focus on these regions is problematic given that these regions represent less than 10% of the world population (Thalmayer et al., 2021). While research on child-parent attachment using observational measures in China has been growing, together with several studies conducted in Japan over the past five decades, there remains a dearth of research on infant-caregiver attachment in Asia. This paucity represents a significant knowledge gap considering the high population density of countries like Indonesia, Pakistan, and India. Moreover, little is known about child-parent attachment relationships in regions of the world, including Asia, Africa, and South America. One important step to achieve the goal of more representations of research studies in these regions is likely conducting more accredited training outside of North America and Europe, where they have been traditionally concentrated. Additionally, collaborations and partnerships between researchers from these regions and underrepresented regions can be instrumental in shrinking the representation gap in attachment research. Trainings provided in China, for example, resulted in an increase of studies conducted there with the SSP (e.g., Liang et al., 2021). Such collaborations can also help mitigate the lack of research funding in some countries that would allow for the use of cost-intensive behavioral observation.
One prediction made by attachment theory is that secure attachment will be associated with more successful socioemotional development than insecure attachment. However, what constitutes successful socioemotional development in a specific cultural niche and how it should be measured are thorny issues, as basic “emic” research in settings that comprise understudied regions of the world is lacking (Posada et al., 2004). Furthermore, cross-cultural validation of observational measures of child-parent attachment, such as the SSP, needs further testing, especially in terms of some core hypotheses in attachment theory that go beyond the mere comparison of attachment distributions. An important methodological consideration concerns the coders of the SSP, as no study, to our knowledge, has compared whether coders from a different culture and those from a local culture would code the same tape similarly. It is possible that coders’ own experiences and culturally shaped expectations would make them see behaviors differently, something that has yet to be tested.
It should also be noted that geographic regions are comprised of highly diverse cultural contexts, with different norms and expectations about parenting, making comparisons between and generalizations across entire continents limited in value. A more detailed approach using multidimensional characterization of cultural differences between smaller geographic regions with a large set of psychosocial and economic scales might better represent cultural niches and provide a more granular comparison of culturally defined meaning of attachment (Muthukrishna et al., 2020).
Risk Contexts
Despite increasing attention to contextual risks, almost two-thirds (61.5%) of all the studies in the published literature on infant-caregiver attachment are drawn from community samples. For instance, 36.3% of the samples in our analysis were characterized as having mid-high socioeconomic background, followed by 24.7% and 17.6% drawn from mixed and low socioeconomic settings, respectively. Underrepresentation of high-risk dyads could mislead regarding family processes if generalizations are made from high-SES families (Sagi et al., 1997). In a recent meta-analysis of the prevalence of attachment distribution across 285 studies conducted to date (Madigan, Fearon et al., 2023), it was found that secure attachment was less common in samples with low SES compared to middle/upper SES (42% vs. 56%). Factors associated with higher rates of insecure infant-parent attachment among samples that face socioeconomic barriers include parenting stressors (e.g., food insecurity) that can result in less sensitive parenting, which is a precursor to secure infant-parent attachment. Furthermore, families with low SES may not have access to resources that can help bolster the caregiving environment (e.g., parenting books, therapeutic treatments; Bakermans-Kranenburg et al., 2005; Bradley et al., 1994).
Indicators of socioeconomic disadvantage often cluster within families with low SES, such as low parental education, single parenthood, parenting stress, household chaos, as well as inter-partner and neighborhood violence (Cyr et al., 2010). These stress-inducing factors could play a role in shaping child-parent attachment relationships by endangering the child’s sense of safety and security and thereby potentially activating the child’s fear system without adequate resolution or regulation, and/or engendering parental withdrawal behaviors (Lyons-Ruth et al., 1999). Thus, it is important that child-parent attachment research continues to pay increasing attention to how socioeconomic disadvantage and other risk contexts may be pathways to disorganized attachment. Understanding these pathways will enable policy makers and clinicians to design effective interventions that mitigate the risk of insecure and disorganized attachment and subsequent poor developmental outcomes in children. Evidence from attachment research of the harms caused by high-risk environments can also underpin calls to take action to change these environments, whether through additional resources or through policy change (Bachmann et al., 2022; Duschinsky et al., 2015; Goldman et al., 2020; Jones-Mason et al., 2021; Kraemer & Roberts, 1996; van IJzendoorn & Bakermans-Kranenburg, 2020).
While we caution against pathologizing ethnicity or suggesting a deterministic relationship between ethnicity and risk, researchers have identified that ethnic minority status may have associations with insecure attachment in the context of other adversities, likely due to the effects of injustice and inequality (Causadias et al., 2022; Coard, 2022; Cyr et al., 2010; Johnson et al., 2003). Ethnic minority populations can sometimes be characterized as vulnerable populations such as new immigrants, refugees, or those who have historically faced discrimination and barriers in accessing social services such as African Americans or Indigenous Peoples. For these vulnerable populations, risks such as socioeconomic disadvantage or trauma resulting from historical events or experiences of social exclusion can play a significant role in shaping child-parent attachment relationships (Alink et al., 2013; Bakermans-Kranenburg et al., 2004; Cárcamo et al., 2015). However, over half (58.9%) of the studies that reported data on ethnic minority status were conducted on samples where a majority of individuals were of non-ethnic minority status and only 8.2% of studies were focused on individuals of ethnic minority status (≥80% of sample). With the average percentage of ethnic minority status represented in child attachment studies being 24.4%, there is room in future studies to examine more closely the factors that shape child-parent attachment relationships among ethnic minority populations. In addition to providing insight into the risks associated with ethnic minority status, perhaps future studies could also reveal the potential protective cultural factors among these populations that influence the development of attachment relationships.
Attention should also be given to the need for more research using observational measures of attachment conducted on clinical samples, such as children with neurodevelopmental disorders (e.g., intellectual disability, Down Syndrome, cerebral palsy) in early childhood and those with a history of psychopathology (e.g., anxiety, depression, behavioral conduct problems) that emerge later in childhood. Researchers have prospectively studied whether infants with insecure versus secure attachment are more likely to develop mental health difficulties later in childhood (Deneault et al., 2021; Fearon et al., 2010; Groh et al., 2017; Madigan et al., 2013). Future research, however, could focus specifically on clinical samples characterized by these conditions (e.g., intellectual disabilities or mental health) to provide more insight into how child risk factors play a role in shaping child-parent attachment relationships or whether intervention programs targeted at these special groups are necessary to mitigate the risk of insecure or disorganized attachment.
Predictors and Outcomes
Many of the predominant variables that have been assessed in child-parent attachment studies, such as child cognitive and language development, child behavior problems, child peer relationships, attachment representations, maternal psychopathology, and parental sensitivity, have been examined in meta-analytic studies (e.g., Atkinson et al., 2000; Barnes & Theule, 2019; Deneault et al., 2021, 2022; Deneault, Duschinsky, Van IJzendoorn, et al., 2023; Madigan et al., 2013; Madigan, Deneault et al., 2024; Pallini et al., 2014; Schneider et al., 2001; van IJzendoorn et al., 1992; van IJzendoorn et al., 1995). The results of these meta-analyses indicate that children who form secure attachments with their caregiver have developmental advantages over those with insecure or disorganized attachment relationships with their caregiver. Results from this bibliometric analysis show that other parental and environmental variables, such as parenting attitude, parenting stress, social support, life events, household context, and marital conflict/satisfaction, have been examined in a sizeable number of studies. Future meta-analyses focusing on these variables could provide further insight into how parental factors or environmental risks affect the development of child-parent attachment relationships.
Assessment of preschool-aged child-caregiver attachment using the SSP-M has increased sharply over the last two decades with 69% of all studies using the SSP-M having been published between the period 2000 to 2019 (38% published since 2010). This trend suggests that researchers are interested in examining child attachment beyond infancy to gain insight into later childhood development, including related child behavioral outcomes, or the stability of child-caregiver attachment relationships over time. With the growth of studies looking at toddler and preschool-aged children, variables to assess child developmental outcomes are receiving more attention, such as the associations between child-parent attachment and children’s socio-emotional development, child behavior problems, child cognitive and language development, and children’s peer relationships.
Limitations
While this study represents an effort to compile as comprehensively as possible the study characteristics of all empirical studies in the field of child-parent attachment research, it is possible that some studies were missed. Moreover, we only include empirical studies in CASCADE and therefore, commentaries, editorials, chapters without data, etc. were not included in this bibliometric analysis. Some older records, even though containing empirical data, may not have been included in online databases given that online data base indexing was developed after these early publications. Measures were in place to ensure reliability of the data; however, one coder was responsible for entering all the studies into the CASCADE database. The research team collectively made decisions regarding study inclusion criteria, which may differ from another research group’s decisions.
Conclusions
Drawing on the CASCADE catalog, we analyzed bibliometric trends in a corpus of 2,318 empirical studies between 1970 and 2023 that used observational measures of child-caregiver attachment. This has highlighted areas of relative strength in the contemporary science of attachment. For instance, we identified a number of parenting factors where many studies have accumulated, and which would be ripe for meta-analytic research. However, our analysis also identified gaps. Three stand out as especially salient. The available research remains limited in its attention to non-maternal caregivers, and a spike of interest in father research in the 1980s has failed to be sustained. We hope that innovative developments such as the creation of the Society for Emotions and Attachment Studies’ Special Research Interest Group on Father-Child Attachment and Relationships may change this. Another limitation is that the overwhelming majority of studies that have used observational measures of child-caregiver attachment have also been conducted in either North America (72.8%) or in Europe (18.9%). Increased availability of training in observational measures of attachment and international collaborations between researchers may reduce this inequality in the future and help to understand more about the role of cultural factors in shaping how attachment relationships develop, and how attachment relationships contribute to later developmental outcomes. Lastly, only 17.6% of samples were drawn from low socioeconomic settings. As the pressures of adversity can be anticipated to impact attachment-related processes in parenting and development, care should be taken in generalizing findings on the basis of samples drawn predominantly from higher socioeconomic settings. Addressing these gaps in future research would increase the representativeness of samples, and generalizability of empirical findings, which in turn would foster a more inclusive understanding of the formation and sequalae of child-parent attachment relationships.
