Abstract
This article provides a circumscribed descriptive analysis of the current state of research worldwide related to adult romantic relationship processes and their underlying mechanisms. A scoping review was used to gather data. This yielded 15,418 eligible articles from 1,687 different academic journals. From these, we outline key themes and theories arising in the last seven decades and note the most prolific journals and authors. The study of relational wellbeing has focused on overt behaviors such as communication and commitment, on underlying attitudes and motives such as empathy and contempt, and on substrates and circumstances such as neurobiological functioning and life stressors. The results reveal the strong interdisciplinary research underpinnings of the field of relationship science and show up key influences over its expansion. Results are intended to give an overview of key peer reviewed research that has contributed to the development of current scientific knowledge and theory development in this field.
Keywords
An Update on the State of Relationship Science Research
Recent years have seen an exponential accrual of broad-ranging evidence pointing to the personal and societal benefits of high-quality adult romantic relationship function. This significant body of relationship information portends an exciting time for relationship scientists as multiple academic disciplines converge in a season of mutually beneficial growth. The enormous scale of this research has led to a “critical mass of clinically compelling theory” (Gurman, 2011, p. 281), which, according to couple’s therapy expert Susan Johnson, has instigated a “relationship revolution” (2013, p. 9). In this paper, we investigate and review the mass of research literature underpinning the science of relationships.
As the published research in this field has burgeoned over the last seven decades, a cross-disciplines review of the literature has become an overwhelming task outside of the purview of many relationship researchers and therapists. Consequently, people working in this essential public health and wellbeing domain may be lacking an awareness of the breadth and depth of the knowledge it contains, or the way in which recent studies are reshaping old therapeutic mandates. Previous reviews have been carried out on a smaller scale, including some by relationship science’s eminent researchers: Huston and Levinger (1978), Clark and Reis (1988), Holmes and Boon (1990), Gottman (1998), and Finkel et al. (2017). However, the pace of research output is such in this era that these quickly get surpassed and no longer necessarily represent the current state of knowledge or prioritization of theory in this field. This study takes a broad and sweeping look at relationship science research over the last 70 years with emphasis on the most recent decade of 2010–2020. As such, it encompasses an investigation of relationship science research and draws from this literature base to understand the ascendency of research themes and topics, giving this study a unique hermeneutic entrance point (Heidegger, 2002) and thereby enabling a fresh perspective on the history, context, and current state of this domain.
The proliferating of relationship science data over the past decades—while making available an extraordinary amount of information regarding its common themes, and theories—has also meant that trying to keep up with the latest findings is like “trying to drink from a fire hose” (Kee, 2014, p. 28). As a way of illustrating the significant and exponential growth in romantic relationship science over the last seven decades, a keyword search was made in EBSCO of the syntax: “(romantic OR couple OR marriage) relationship.” The search was limited to books, reports, conference materials, dissertations, and academic journals. This search was further demarcated to ten-year periods since 1920. Figure 1 illustrates this growth. Scholarly publications from 1921 to 2020 using the syntax: “(Romantic OR couple OR marriage) relationship.”
As far back as 1953, the proliferation of interdisciplinary scientific research concerned the renowned theorist Ludwig von Bertalanffy who foresaw that with so much data to study, specialization in narrow scientific fields could result. Specialization, while advantageous in many ways, risks a siloing of scientific branches of knowledge, and subsequently a loss of valuable collaboration and sharing of common understanding. In addressing this he wrote: “In so far as the advancement of science is concerned, history shows that interconnection of different fields and problems is a most important basis of progress” (von Bertalanffy, 1953, p. 233). Decades later, in her summary review “The Greening of Relationship Science,” Berscheid (1999) exhorted relationship researchers to work toward coherence among the myriad of scholarly fields involved. More recently, relationship scientists Timothy Loving and Ted Huston wrote of their hopes that relationship science would “overcome the disciplinary isolation that undermines a holistic understanding of relationships” (Loving & Huston, 2012, p. 275).
Despite these valid petitions, the task of negotiating and uniting the flurry of information has become increasingly more difficult simply due to the sheer amount of it. The abundance of new data and the speed at which it is being produced can slow down integration of new theory into existing theory. Melchert (2016, p. 486) wrote in his appraisal of the psychology profession: “So much has been learned about human psychology recently that current explanations of many psychological mechanisms and processes are markedly different from those considered current just a generation ago.” The mass of data relevant to romantic relationship processes continuously needs updating. Yet, this updating is no small task and any serious attempt at evaluating such a broad criterion of data requires both a robust organization of the information and a refining of that information in relation to both existing and arising theories (Reichertz, 2004). This study therefore set about investigating the breadth of research relating to romantic relationship processes across disciplines, and delved into the key themes, theories, journals, and authors, rising to the fore through the decades, with the intention of clarifying the current position of academic relationship science research.
Method
A wide-ranging scoping review was utilized to research this study. Scoping reviews are sweeping in nature and therefore a method suited to exploring the current state of an especially broad research domain such as human relationships (Munn et al., 2018). Arksey & O’Malley’s (2005) scoping review framework and their eligibility criteria were used as a guideline. An extensive search was made of academic literature databases to collate data that related to romantic relationship processes and mechanisms. Data were then edited, reviewed, organized, and analyzed.
Eligibility Criteria
Studies were included if they: a) involved peer reviewed research; and b) illuminated an aspect of the adult romantic relationship processes and their underlying mechanisms. No restrictions were imposed on the language (where translatable to English), or country of origin. Grey literature was excluded on the grounds that their methodological value was difficult to ascertain (Lawrence et al., 2015). No restrictions were placed on year of publication resulting in a date range of 1922–2020; however, issue by issue searches of journals were only made for the decade 2010–2020 due to time limitations and following guidance to prioritize recency and credibility (Ward et al., 2016). Duplicate records were removed.
Identifying Relevant Studies
Relevant studies were identified by searching keywords, key journals, key researchers, and key theories methodically and heuristically.
Keyword Search Method
Keywords (and their truncated variants) describing the population and phenomena of interest were investigated using this initial search syntax: (relationship* OR couple* OR relational OR marital OR marital relation* OR marriage OR close relationships OR romantic OR cohabit* OR partner*) AND (satisfaction OR health OR function* OR conflict OR happiness OR wellbeing). This syntax was applied to electronic databases including EBSCO, OVID, PubMed, PsycINFO, SAGE, Scopus, MEDLINE, Web of Science, and Wiley. This search showed up 19,630,389 articles. These were screened for applicability to the research question by reading the titles and those that seemed applicable (related to romantic relationship processes and mechanisms) were retained. This initial search collected 11,218 articles of interest which were all loaded and edited into Endnote—a software tool commonly used for managing academic references (Peters, 2017).
To determine key constructs dominating these articles, 525 key articles pertaining specifically to adult romantic relationship theory were added into NVivo (qualitative data analysis software) and a word search was run on them. This showed up additional high use words that had been missed in the original syntax search including emotion*, behavior*, sex*, dyadic, satisfaction, divorce, dissolution, separation, interaction, interpersonal, couple*, communication, commitment, personality, neuroscience, physiolog*, husband, wife, wives, coping, stress*, motivation, neuroticism, values, and cultur*. Further searches were carried out using these words until saturation occurred. At the end of this stage of research, with repeated investigation of these topics, 15,403 additional articles had been collected into the Endnote database. Every abstract was read through and used to inform thematic categories. Each article took approximately 15 minutes to search out, download, clean, read, and assess. Extrapolated out this meant more than two full-time years of data collection by the primary author, while simultaneously staying up to date on new publications.
Themes were determined by the wording of the title and abstracts of each article. Some articles were grouped into more than one theme where the overlap was obvious. For example, the article titled “Too close for comfort? Adult attachment and cuddling in romantic and parent–child relationships” (Chopik et al., 2014) was grouped under both “attachment style” and “sex and affection.”
Journal Search
The 15,403 articles originated from a total of 1,687 different journals. These journals were tabled and those from which more than 10 articles had already been gleaned were trawled extensively, issue by issue, from 2010 to 2020. Relevant articles missed in the keyword search were thus garnered. A total of 219 journals were investigated in this manner. An additional 3,112 articles were thus added to the Endnote database.
Researcher Search
Following this, an investigation was made of the work of influential relationship researchers. In Endnote, more than 6,000 individual authors were searched and those who had contributed more than 10 articles as the lead author were identified and added to an excel file. A total of 504 authors were thus investigated. At this point, to clarify the most significant contributors specifically in the area of relationship processes, the data were coded into five groupings. Group 5 included articles deemed most relevant to the study of romantic relationship processes and mechanisms (N = 689). Group 1 included articles deemed least relevant, or having no relevance to the research question, or lacking peer review or sound methodology (N = 6,113). The first authors of studies coded into Group 5 were further searched. As a result of these searches, an additional 2,523 articles were added to the Endnote database.
Theory Search
Finally, an investigation was made of relevant, noteworthy, and influential models and theories. Seminal theory identification occurred through reading the article abstracts of those articles coded into Group 5 (most theoretically relevant to the study of romantic relationships). “Theory” was defined in this study as that which logically relates propositions in order to systemize knowledge, explanation, and prediction (Carpiano & Daley, 2006). In the literature, the term theory may also be defined as a conceptual framework or model. Each of these was considered viable for use in the theory search.
A total of 530 relevant theories were identified. An open field (entire PDF article search) Endnote database search was carried out for each of these theories. This showed up the number of articles mentioning the theory at least once in their content throughout the database. Those theories mentioned in more than 300 articles (N = 30 theories) were further searched online. An additional 493 articles were added to the Endnote database as a result of this search, bringing the total number of articles to 21,531. Those coded in Group 1 (N = 6,113) were then excluded due to lack of eligibility bringing the total number of articles used in this study to a final figure of 15,418.
PRISMA Flow Diagram
A brief overview of the scoping review process is outlined in Figure 2. This is a version of the PRISMA Scoping Review Flow Diagram (based on Moher et al., 2009). Scoping review flow diagram.
Results
Key Word Search Results
Number of articles per theme.
Journal Search Results
Number of articles per journal.
These 20 journals comprise just over 1% of the overall journal pool (N = 1,670) in this study and yet provide 42% (N = 6,502) of the utilized research data.
Researcher Search Results
Number of articles per author.
Together, these 20 researchers provide 10% of the utilized research in this study while representing only 4% of the authors. Of note, of the 20 most prolific relationship science authors found, only four are women. Most researchers (75%) are based in the United States, with one (Peter Kuppens) from Belgium, one (Guy Bodenmann) from Switzerland, one (Nickola Overall) from New Zealand, one (Mario Mikulincer) from Israel, and one (Emily Impett) from Canada. The populations of research are similarly from predominantly first world nations grounded in historic European ideals of marriage and family structure.
Theory Search Results
Number of articles per theory.
Other commonly used theories specific to romantic relationships included: The actor–partner interdependence model (APIM) (Kashy & Kenny, 1999); Love styles (Hendrick & Hendrick, 1986); Interpersonal circumplex theory (IPC) (Leary, 1957; Wiggins & Trobst, 1997); Sociometer theory (SMT) (Kirkpatrick & Ellis, 2001; Leary & Downs, 1995); Reinforcement sensitivity theory (RST) (Gray, 1973); Self-expansion model (Aron & Aron, 1996); Triangular theory of love (Sternberg, 1986); Social baseline theory (SBT) (Beckes & Coan, 2011); Relational competence theory (L'Abate, 2010); Relational turbulence model (Solomon & Knobloch, 2004); The family stress model (Conger et al., 2010); The sound marital house (Gottman & Silver, 1999); Relationship self-regulation theory (RSR) (Halford et al., 1994); Risk regulation model (Murray et al., 2006); Affection exchange theory (AET) (Floyd, 1997); Convoy model (Levitt, 2005); and The circumplex model of marital and family systems (Olson, 1989).
The most recent theories are also interesting to note. These are generally built upon the wealth of older theories and give an indication of their cumulative impact. Emerging theories and models include: Hierarchical model for interpersonal verbal communication (Jiang et al., 2021); The emotional bookkeeping hypothesis (Schino & Aureli, 2021); Reciprocal impact of relational conflict on physiological resilience (Kiecolt-Glaser et al., 2021); Happy, healthy, safe relationships (HHSR) continuum (C. Murray, Ross et al., 2020); The quadruple theory (Tobore, 2020); Culturally based romantic relationship (CBR2) model (Fonseca et al., 2020); Love as caring maturity model (Hedayati, 2020); Microbial effects on social behavior (Sarkar et al., 2020); Model of the social-safety system (S. Murray, Lamarche et al., 2020); and A gene-environment model (Paris, 2020).
Discussion
This study sought to investigate and analyze the current state of research worldwide related to adult romantic relationship processes. An initial search showed more than a 600-fold increase in romantic relationship related research papers being published over the last 70 years. A scoping review was used to gather data. The results of this scoping review yielded 15,418 eligible articles which were encoded into Endnote. The articles originated from 1,687 different academic journals indicating the breadth of interest in human relationships across diverse fields of science. Of these journals, 219 were extensively searched for the decade 2011–2021.
Themes were drawn from each article’s title and abstract. These themes included: Personality, genetics, expectations, mental health, aggression and attachment, gender differences, cognitions and beliefs, empathy, societal expectations, social support options and life stressors, control and power, capitalization, conflict, communication, intimacy, and vulnerability, taking influence and interdependence, relationship maintenance, and sex and affection. These lined up with the dominant pre-existing theories noted in the research, of which those most commonly referred to were: Attachment theory (including adult attachment theory); Big Five personality model (personality theory); Mindfulness; Emotional intelligence; Theory of mind; Appraisal and attribution theories; Biopsychosocial and systems theories; Emotionally Focused Theory; Bowenian theory; Demand-withdraw theory; The Investment Model; Dyadic coping and stress theories; Self-Determination Theory; Regulatory Focus Theory; Evolutionary theory; Adverse Childhood Experiences; Parenting styles; Interdependence Theory; Gene-environment models; Assortative Mating Theory; Implicit theories; Perceived Partner Responsiveness Theory; Social Learning Theory; and Social exchange theories.
The dominant publishing themes of the most prolific relationship science related journals include: Understanding the bio-social nature of human being and human relating; relationships between human social, psychological, and behavioral features and bodily processes; individual differences in personality and the factors stimulating these differences; cognition and emotion and their structure and regulation; promotion of healthy relationship processes and mending of dysfunctional ones; family relationship networks and larger systems; and family therapy.
The main topics and themes investigated by the most prolific relationship researchers included: Close relationships and interpersonal processes; resolving conflict and enhancing relationship success; communication patterns in relationships; relationship trajectories; psychological processes that affect the course and conduct of close relationships; theories of emotion appraisal and individual differences; emotional regulation; dyadic coping and stress; prediction of divorce and relationship distress; attachment; social support; approach-avoidance motivation in close relationships; goal achievement in relationships; relationship perceptions and appraisals; humor; personal relationships and forgiveness; interpersonal attraction; romantic relationship development and functioning; personality and social risk factors; commitment in romantic relationships; affective neuroscience; Emotion Focused therapy (EFT); Integrative Behavioral Couple Therapy (IBCT); the demand/withdraw pattern; relationship education; cross-cultural and lifespan factors in relationships; and sexual satisfaction. It is clear from this broad array of key themes and theories that across the decades researchers in relationship science have traversed multiple disciplines.
Considerations and Limitations
The results of this study are intended to give an overview of key peer reviewed research that has contributed to the development of current scientific knowledge in this field. It places relevance on article output rather than more commonly used determinants such as citation count or methodological reliability and validity. This alternate method of considering relevance provides a new perspective on the research journey of the field of relationship science. Nonetheless there will be articles missed and additionally articles unnecessarily gathered due to the vast extent of the available literature. Theory and theme names have sometimes been altered over the decades leading to under represention in the word searches therefore skewing the results. Additionally—as some articles were pre-1985, their PDFs were not searchable by Endnote, consequently reducing the identification of these terms. The results are therefore presented not as a definitive answer but more as a discourse that helps reduce rather than eliminate uncertainty regarding the current state of the research underlying relationship science in the current era.
Time changes research ethos and correspondingly theories evolve and transform. Concepts of interest and relevance rise and fall in and out of favor. In this study, only key journals over the past decade were searched by edition. As a result, articles from earlier decades will inevitably have been missed and this will have skewed the results in favor of more recent material and theories. Nonetheless, as this study covers a period of 70 yearsthose theories developed earlier in the growth of relationship science will have much greater length of exposure in the collective research than those published only in the last decade. The older theories and models have had more opportunity to be read, and utilized, and therefore integrated into research processes and included in more recent publications. While older theories tend to therefore represent those most populous in the literature, it is prudent to note that this does not necessarily mean they are theories that are most helpful to the understanding of romantic relationship processes or those most utilized by current therapeutic practitioners. However, the fact that older theories have not only endured but have also continued to be of use to researchers is an indication of their relevance, validity, and reliability (Fesmire, 2014). On the flip side, their continued use could also be an artifact of researchers failing to keep up to date with the overwhelming amount of new research and any changes that these might suggest.
This overview has highlighted a culture and gender bias in the research. The majority of journals publishing romantic relationship research are based in the United States of America, and the few that are from other nations are predominantly based in western, educated, industrialized, rich, and democratic (WEIRD) nations, which comprise only about 12% of the world’s population (Henrich et al., 2010). Approaching research from a westernized mindset can bias the methodology used as well as the results garnered, given that the populations being studied represent a particular cultural paradigm. Although many relationship science theories have been shown to be replicable this is an area of research needed to advance the robustness of relationship science findings (Cronbach et al., 1972; Shavelson et al., 1989).
In a similar vein, the majority of authors were men with women vastly under-represented. While a recent study has shown that women are approaching gender parity in psychological research contribution (46.4% of APA authorships (Gonzalez-Alvarez & Sos-Pena, 2020)), the accumulative record is still skewed in favor of male researchers. Many of the studies in this collation note gender differences in men and women’s approaches to relationship processes. Therefore, we can also expect that there will be differences in the way men and women approach researching relationship processes. In this study, there was an analogous potential for a gender bias in the coding of key topics, both in regard to the authors’ bias and the bias of the literature from which codes were drawn from.
Looking Forward
This study places relevance on productivity across disciplines. As such, it provides a unique perspective on the research journey of the field of relationship science and the emphases that have directed its growth. This perspective may be helpful for those working in the field who do not have the opportunity to broadly investigate the scientific foundations of their practice. It provides a sweeping general view of the state of the field rather than a granular conceptualization of whether this is the state it should be in. The study is limited by the enormous amount of data available to collect and thematize and the inevitable incompleteness of this process. It nonetheless offers a representation of pertinent relationship science literature—especially that which has been published in the last decade—and alludes to its developmental influences. It offers therapists and researchers an insight into the most likely journal sources and authors relevant to romantic relationship knowledge. In homing in on the most drawn upon theories, it may aid educators in understanding the underlying knowledge base around romantic relationship theory. This may also help clinicians in fulfilling their discipline’s core competency briefs—which often include demonstration of a knowledge of the history, theory, and research literature relating to their area of practice (e.g. New Zealand Psychologists Board, 2018).
This study illuminates strengths in the field of relationship science, including the extensive research regarding the ways in which relationship outcomes are impacted by attachment style, personality, mindfulness, emotional intelligence, theory of mind, and attributions and appraisals. These theoretical concepts stand out as the most relevant, valid, and reliable in this area of relationship science due to their continued and popular use and consequent recurrent testing (Peirce, 1878). Further cross-disciplinary investigation into the key findings of multiple researchers may lead to greater clarity around romantic relationship processes and mechanisms via “structural corroboration” (Eisner, 1998, p. 55). In addition, some recent theories were exposed that may prove fruitful for future avenues of inquiry. Of note, research funders could consider the addition of more female authors/researchers and more authors/researchers studying non-first world populations.
Conclusion
Relationship research is complex due to the broad nature of the phenomena under investigation. Many contextual factors influence our understanding and explication of these phenomena and the theories we formulate around them. This study is a starting point for lessening some of that complexity by providing a grounding in the research context that has brought relationship science to this point in history.
Footnotes
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.
