Children in dual-residence arrangements: a literature review

ABSTRACT

Dual residence is a post-divorce living arrangement where children spend up to 50% of their time in each parent’s household after separation or divorce. Reflecting societal changes and shifting norms, these arrangements have increased in many Western societies during recent years. The consequences for children have attracted much interest, resulting in a growing body of research. This literature review has a broad scope, reviewing three decades’ international research about children’s dual-residence arrangements (111 peer-reviewed articles in total) with the aim of analysing the development of the research field. Findings demonstrate that research on the topic has progressed since the first-generation studies and reached several important conclusions. However, it is geographically restricted and heterogeneous in terms of disciplinary perspectives, the choice of aspects to investigate, methodology, data and research design. Furthermore, diverse terms, definitions and cultural, demographic and jurisdictional contexts complicate cross-country comparisons. While some distinct components of dual-residence arrangements seem to increase the likelihood of positive outcomes for children, this study points out the difficulties in using the cumulative body of research in the field when drawing conclusions and making recommendations for practice. Despite the rapidly growing body of research, essential gaps in our understanding of dual residence still remain.

KEYWORDS:

• Dual residence
• joint physical custody
• shared parenting
• children
• post-divorce

Introduction

Today, an increasing number of children grow up in family arrangements other than the nuclear family, due often to high numbers of separations and divorces. One way of arranging children’s housing and care after separation¹ is dual residence (also known as shared residence, joint physical custody, shared physical custody or shared parenting), where children live with each parent, alternating their home life across two households. The definition differs between countries, the child living between a quarter and a half of the total time with each parent (Smyth, 2017). Over the last 40 years, post-separation dual-residence arrangements have gone from extremely rare and practically unknown to being a feasible choice for parents in many countries.² However, the prevalence and development of dual residence differ significantly across regions and it remains essentially a Western phenomenon.

Historically, the organization of the family has changed over time. From a long-term perspective, divorce and separation are recent phenomena. From the 1960s, divorce rates started to rise in the West and have currently reached a rate of ∼50% in many countries in Europe, the US and Australia, according to available statistics (Australian Bureau of Statistics, 2016; CDC, 2019; Eurostat, 2017). Currently, divorce rates have begun to decline in some regions, especially among the most educated segments of the population. However, the fact that many contemporary relationships do not last a lifetime raises a number of new questions regarding the composition of family over time. For example, in what ways can everyday life with children be organized after parental separation? Until recently, the most common model was a residence arrangement where the mother was the primary caregiver and children saw their father less often, typically every second weekend (Andreasson & Johansson, 2019). This pattern is currently giving way to other arrangements, for instance, where childcare is shared more equally after separation. Such post-separation arrangements have come about in line with a changing society with developing ideas regarding equality between the sexes, mothers increasingly being part of the labour force, a growing conscience about fathers’ responsibility for childcare and changing ideals of fatherhood (Andreasson & Johansson, 2019; Melli & Brown, 2008). As expected, dual residence is more common in countries where these ideas are well established, such as Sweden and Norway. In addition, the definition of dual residence in these regions tends to be closer to equally shared time (Kitterød & Wiik, 2017).

In line with its growing popularity, dual residence has generated a rapidly growing field of research across the globe, particularly focusing on its potential benefits and risks and whether it is in ‘the best interest of the child’ (Smyth, 2017; Steinbach, 2018).

Not only have changes in post-separation residence patterns attracted a growing body of research from different disciplinary fields, there is also great public interest as well as a great amount of attention among practitioners and policymakers. The debate about dual-residence arrangements and potential legal presumptions has been an intensely debated issue in family law. At the same time that the research reviewed here was carried out, legislation concerning ‘shared parenting’ has been discussed, passed or rejected in many countries (e.g. Davies, 2015; Poortman & van Gaalen, 2017; Smyth & Chisholm, 2017; Vanassche et al., 2017).

Looking into children’s residence arrangements, post-separation comes at the right time, given the great interest from professionals, academia and policymakers. Above all, the topic affects a large number of children and their families in the process of divorce or separation. Given the high numbers of union dissolutions, the topic is highly relevant to many people.

The aim of the present literature review was to map out the research field exploring the issue of dual residence. More specifically, we aim to investigate the metadata of the research (when, where, who and how) and their purposes and study findings (what). Based on the results, we aim to identify current knowledge and knowledge gaps regarding dual residence.

Materials and methods

The scope of this literature review was comprehensive and we aimed at addressing as much of the published literature as possible. The procedure is outlined below in detail.

Search strategy

To identify relevant studies, we conducted a systematic database search. Peer-reviewed academic articles on any aspects of children’s dual-residence arrangements published before 1 January 2019 were searched.

The selection of relevant articles was conducted in several steps. Initially, relevant search terms were nominated, tested, modified and selected. Reflecting the lack of a common concept and definition, a range of search terms or phrases were chosen, including ‘Joint physical custody’, ‘shared physical custody’, ‘dual residence’, ‘alternating residence’, ‘shared residence’, ‘shared parenting’, ‘shared time parenting’, ‘equal parenting’ and ‘shared care’. By using Boolean operators, the aforementioned terms were combined with ‘divorce’ or ‘separation’ to construct specific search queries and delimitate the search. The search was narrowed by only searching within the title, abstract and keywords. Sixteen electronic databases were considered relevant for the topic.³ Together, these databases cover a broad range of scientific journals in the social sciences. The search resulted in an array of articles covering a broad area related to dual residence.

Eligibility and exclusion criteria

The retrieved hits were analysed by abstracts to evaluate their relevance according to the focus of the review. The criteria for inclusion were that the articles (1) focused on children’s post-divorce or post-separation residence arrangements in which the proportion of time spent in each home varied from one-quarter to an equal share, (2) were peer-reviewed and (3) were written in English. Consequently, only journal articles were included, while books, dissertations, research reports, conference papers and unpublished papers were excluded. However, journal articles were excluded if the full text of an article was not accessible, which was the case in a couple of the early studies.

Selection of journal articles

The database searches generated over 700 journal articles. Due to the broad search terms, a large proportion of them were out of scope. Some focused on the effects of divorce or separation rather than dual-residence arrangements or studied parents rather than children (i.e. fathers’ well-being after divorce or mediation services for parents), while a few were editorials and many were indexed in multiple databases. After a provisional evaluation, 140 of the articles were identified as relevant to the topic. After reading the full-text publication, further articles were excluded because they did not meet the inclusion criteria. Early studies (mainly conducted in the 1980s and 1990s) tended to be less detailed when it came to defining residence arrangements, often without distinguishing joint legal from joint physical residence, which made comparisons difficult. As a result, these studies were excluded (among them the much-cited meta-analysis by Bauserman, 2002). Finally, a small number of articles were added manually as they were referred to by the previously included publications, yielding a total sample of 111 journal articles that were included in the study. The majority of the articles was found in Sociology Collection, PsycINFO, and Sociological Abstracts (but many were indexed in multiple databases).

Analysis

The selected studies were subjected to a thematic analysis in two steps. Initially, the paper characteristics were recorded in a matrix comprising the following six categories: Author/date/country, Aim/research questions, Definitions, Design/recruitment/sample, Measures/analysis and Results/primary findings. In the next step, the analysis focused on the content of the aim/research questions and the results/primary findings of the studies, yielding six distinct themes. These were labelled: Adjustment, physical and psychological health, social and emotional well-being, Conflict between parents – its impact on children’s well-being or outcomes, Family characteristics, Parent–child relationships and communication, Children’s views and experiences of dual-residence arrangements, and Policy and law. There were also some studies that we could not fit into any of these themes. These uncategorized studies were not included in the subsequent analysis.

Methodological limitations

There is always a risk of overlooking relevant articles, regardless of how comprehensive searches may be. As the review is limited to research published in English only, there is a risk of omitting important studies published in other languages.

Results

Characteristics of the selected studies

A total of 111 studies were selected for the current study. The first study in the sample was published in 1984 and since then the field has grown substantially. The analysis shows that 6 papers were published in the 1980s, 7 in the 1990s, 19 between 2000 and 2009 and 82 between 2010 and 2019. While the first study identified came from the UK (Irving et al., 1984), other studies on dual residence before the millennium were all conducted in North America. Between 2000 and 2009, half of the studies emanated from Australia and the other half came from European countries and North America. In the 2010s, the analysis reveals four geographical clusters with 22 studies from the Nordic countries (16 from Sweden, 5 from Norway and 1 from Iceland), 18 from North America, 15 from Belgium and the Netherlands and 13 from Australia (five studies from the UK, one from Austria, and one from Germany). A handful of these studies were cross-cultural collaborations, mostly with two countries involved. Several publications emanate from distinct research groups that use the same study sample in multiple studies, focusing on different research questions or sub-samples. Thus, even though there are a relatively high number of publications, several are interrelated and results clustered. This does not necessarily bias the conclusion, but it is relevant to ask if the results are sample-specific.

The definition of dual residence varies among the studies in the sample. To be categorized as living in a dual-residence arrangement, the minimum time spent with each parent ranges from ∼25% (e.g. Buchanan et al., 1991) to 50% (e.g. Fransson et al., 2016). The 50/50 definition is more prevalent in studies published in the 2010s and more specifically in the studies emanating from Sweden, Norway and the UK, while the North American and Australian definitions have mostly ranged from 25/75 to 35/65% (the definition of 25/75 is mainly used in older studies). Studies from Belgium make an exception to the most widely used European definitions and commonly use 33/67% as the breaking point to describe dual-residence arrangements, while in Dutch studies, definitions range from 30/70 to equal-time arrangements.

The selected sample in this literature review comprises studies with both qualitative and quantitative research designs, including several literature reviews. The majority of the empirical studies use a quantitative approach with sample sizes ranging from around 100 to 15,000 respondents. One notable exception is two school-based studies from Sweden comprising 145,000–165,000 children (Bergström et al., 2013, 2015). The vast majority of these studies used a cross-sectional design while only a few longitudinal studies were found. Data were collected by standardized interviews as well as via traditional questionnaires, while the statistical analyses applied varied from uni- and bivariate analyses to more complex multivariate analyses.

In the sample, 17 qualitative studies were identified, most using semi-structured face-to-face interviews. Most of the qualitative studies were conducted in the 2010s, primarily in Australia and Europe. As qualitative studies have been added to the body of research, there has also been a shift in study subjects in both qualitative and quantitative studies; from parents and professionals to children.

In the current study, 16 of the selected studies were categorized as meta-studies or reviews. Significant for these studies was that their aims were limited to a specific topic within dual residence, for example, children’s well-being, children’s adjustment, qualitative studies on children’s experiences and shared parenting focusing on a specific region, for example, the Australian or the North American context (e.g. Meyer et al., 2017; Poortman & van Gaalen, 2017; Smyth, 2009). In addition, most of these were small scale, the literature reviews by Steinbach (2018) and Nielsen (2017, 2018) being exceptions with their 40, 44 and 60 studies. Meta-studies also often did not disclose any information on how the studies were selected (e.g. inclusion and exclusion criteria).

The remaining, uncategorized studies (n=20) included in the current literature review, include policy debates, commentaries, conceptual papers and evaluations of law reforms.

Although it may also be an effect of the inclusion criteria, by limiting database searches to the English language, there was a notable absence of non-Western studies in the selected sample.

Themes in the selected studies

As mentioned above, six distinct themes were identified among the selected studies. In most cases, the studies could be attributed to a single theme, but some of the studies comprised a broader focus that fit into several of these themes.

Adjustment, physical and psychological health, social and emotional well-being

Early research, primarily US-based, focused almost exclusively on adjustment – asking how dual residence affected children. Thematically, this has continued to be the focus for several empirical studies, but over time, a more child-centred point of departure has emerged. The outcomes for dual-residence children are often compared to those of children living in other post-divorce arrangements, but occasionally also to those living in nuclear families. There is broad consensus that children living in nuclear families are less prone to illness and maladjustment than those with separated or divorced parents (e.g. Amato, 2010; Bergström et al., 2014; Breivik & Olweus, 2006; Carlsund et al., 2013; Wadsby et al., 2014). One common explanation is that divorce results in the loss of the relationship with one parent (often the father) and reduces the financial, social and emotional resources of the non-resident parent (Steinbach, 2018). However, this explanation does not take into account the growing number of children in dual-residence arrangements, where both parents continue to share the care of the child, albeit in two separate homes. Consequently, one could ask whether dual residence might mitigate these negative effects of separation. For children in dual-residence arrangements, there is largely consensus among researchers that children in dual-residence arrangements are equally well, or often better off in several ways (health, risk, etc.), than children living with one parent only. This has been showed in numerous studies from different countries (e.g. Bergström et al., 2013, 2018; Fransson et al., 2016, 2018; Gilmore, 2006; Glover & Steele, 1988; Jablonska & Lindberg, 2007; Shiller, 1986; Spruijt & Duindam, 2010; Turunen, 2017; Turunen et al., 2017). However, the consensus is only valid when there is no ongoing conflict, if parents are able to cooperate and if children are above the age of four (McIntosh et al., 2013; McIntosh & Chisholm, 2008; Vanassche et al., 2013). In the case of great parental conflict and for very young children, the benefits of dual residence have been disputed and have divided researchers into two camps – advocates and opponents. Regarding young children, the key issue seems to be a concern about insecure attachment, which in turn has its roots in the interpretation of attachment theories that for a long time stressed the importance of the mother–child link, one for which it was said there was no substitute (Bowlby, 1969). Less rigid interpretations and later incarnations of attachment theory suggest that the child may attach to multiple caregivers (Kelly & Lamb, 2000). However, the idea of a primary parent still seems prevailing in many studies. Apart from insecure attachment, concern has been raised that the young infant has neither memory nor language capacities to support an understanding of repeated separation or to predict reunion (McIntosh et al., 2013). To this point, there are only a few empirical studies, mostly focusing on overnight stays with the second parent rather than dual residence. Moreover, the interpretations of these results have generated a heated debate among a group of researchers (e.g. McIntosh et al., 2013; Warshak, 2014). This controversy is visible not only in research studies but has also generated commentaries and policy debates that reach outside of the research community, for example, in the fathers’ rights movement. The available literature reviews on the issue suggest overnight stays with both parents are unproblematic in general (Nielsen, 2014, 2017; Warshak, 2015, 2018), although more research is undoubtedly needed in this regard. Pruett and colleagues (2014) suggest that sensitive parenting and flexible schedules are more important for children’s well-being than the number of overnights, but point out that it is not yet known how such flexibility and sensitivity should be performed in practice (Pruett et al., 2014).

While a large proportion of the literature poses broader and more general research questions on children’s adjustment post-divorce and compares different living arrangements to each other, there are a growing number of studies that focuses on different aspects of dual residence. Three of these aspects will be discussed below, namely conflict, family characteristics and parent–child relationships.

Conflict between parents – its impact on children’s well-being or outcomes

Throughout the years, conflict between parents has been identified as having a negative impact on dual-residence arrangements (Haugen, 2010; McIntosh, 2009; Sadowski & McIntosh, 2016; Vanassche et al., 2013). Studies have found that children and adolescents are likely to feel caught between parents if there is severe conflict, which increases the risk for children’s behavioural and psychosocial problems (e.g. Maccoby et al., 1990; McIntosh, 2009). Living within and between ongoing disputes, persistent conflicts and emotional pre-occupation may make dual residence a bad solution for some (e.g. Maccoby et al., 1993; McIntosh, 2009; McIntosh & Chisholm, 2008; Sigurdardóttir et al., 2018; Sodermans et al., 2013). However, it has been argued that dual residence is still the better choice, as the stress of ongoing severe parental conflict is outweighed by the positive impact of keeping a good relationship with both parents (Fabricius & Suh, 2017; Nielsen, 2017; Warshak, 2014). For example, a recent review suggests a closer link between later outcomes for children and the quality of the parent–child relationship, than between outcomes and the degree of parental conflict or the quality of co-parenting (Nielsen, 2017). Mahrer et al. (2018) suggest that the negative effect of inter-parental conflict depends on whether conflict is persistent over time. They found that having a high-quality relationship with parents is linked to better child adjustment, even in high-conflict families. In summary, the empirical results point in different directions and the benefits of dual residence in cases of high conflict are intensely debated.

Family characteristics

One question that has occupied researchers since Shiller’s 1986 study (Shiller, 1986) regards the characteristics of the families living in dual residence arrangements. Sometimes, this has been the primary focus of studies and sometimes has been part of a larger set of research questions. Taken together, regardless of when and where these studies have been conducted, they suggest unanimously that parents opting for dual residence are well educated, employed, and have higher income than comparison groups (Bakker & Mulder, 2013; Bala et al., 2017; Fransson et al., 2018; Juby et al., 2005; Kitterød & Lyngstad, 2012; Kitterød & Wiik, 2017; Melli & Brown, 2008; Meyer et al., 2017; Poortman & van Gaalen, 2017; Sigurdardóttir et al., 2018; Sodermans et al., 2013; Turunen, 2017; Wadsby et al., 2014; Weston et al., 2011). However, a few recent studies show that as dual residence becomes more common, these families differ less in terms of socioeconomic characteristics (Kitterød & Wiik, 2017; Vanassche et al., 2017). Some studies also show that in dual-residence families parents live relatively close to each other, are child-centred and practiced a symmetrical task division during their partnership before the divorce (Bakker & Mulder, 2013; Lidén & Kitterød, 2019). In addition, parents seem to be satisfied with this arrangement for themselves and their children (Bala et al., 2017; Bergström et al., 2014). In research where grandparents have expressed their views, they have described positive experiences (Juliusdottir & Sigurdardottir, 2014). While some studies have found that these families mostly comprise low-conflict couples, this has been contested in at least one study suggesting no differences in levels of conflict (Sodermans et al., 2013). Still, it seems like one important aspect (and the potential outcome) may be related to the fact that many of these parents have chosen this arrangement together.

Parent–child relationships and communication

Another theme focused on parent–child relationship and communication. These studies suggest that parental responsiveness and co-parental communication is strongly associated with a positive outcome of dual-residence arrangements (Francia & Millear, 2015). Furthermore, there is a consensus in the literature that children in most circumstances benefit from sustaining close contact with both parents (Steinbach, 2018). Smyth (2005) found that family dynamics along with socio-demographic factors affect the form that parent–child contact takes after divorce. Another study reported that parent–child relationships and satisfaction with material resources were associated with children’s psychosomatic health (Bergström et al., 2015). The benefit of maintaining a close relationship and receiving support from both parents is often suggested as one explanation of the well-being of children in dual residence. Additionally, having sustaining relationships also implies having access to the (psychological, social and economic) resources of both, as pointed out by Steinbach (2018). Not surprisingly, dual residence is associated with stronger ties between children and their fathers (Melli & Brown, 2008; Spruijt & Duindam, 2010). Whether this is an effect or a precursor of dual residence merits further attention. Poortman (2018), who investigated pre-divorce involvement, found that the association between father–child contact and child well-being depends rather on active father involvement before separation, especially if fathers were emotionally attached with the child in their early developmental phase (through fathers’ parental leave).

Regarding parent–child communication, Bjarnason and Arnarsson (2011) have shown that children in dual residence arrangements, along with children living in nuclear families, find it easier to talk to their parents than children living in other residence arrangements. This is also the case shown in a qualitative Icelandic study where grown up children expressed their views about growing up in equal share arrangements (Sigurdardóttir et al., 2018). A Swedish study noted that children in dual residence were also more likely to turn to parents about problems than children in sole residence arrangements (Låftman et al., 2014).

Children’s views and experiences of dual-residence arrangements

While largely absent in earlier studies, the child perspective has become more prevalent over time. In many recent studies, children are respondents in surveys, as well as interviews. In this section, we focus particularly on nine studies where children themselves were asked about their experiences and views on dual- residence arrangements. For many children, their family situation changes over time as their parents may meet new partners, increasing the number of new close relationships. However, even though the number of social ties is multiplied, this may not be true of close ties. According to the findings of Zartler and Grillenberger (2017), close ties remained exclusively for parents, siblings and best friends. In a study by Berman (2015), on the other hand, new relationships with step-parents or step-siblings sometimes served as important emotional resources. Relationships with the parents they had grown up with were however found to be crucial (Berman, 2015; Sadowski & McIntosh, 2016; Zartler & Grillenberger, 2017). Berman (2015) found that children perceived that they got more attention and spent more time with each parent after the divorce and started reflecting on family and family ties in new ways. This may serve to strengthen the already existing relationships, but also to question and challenge them. In fact, many children spoke of closer relationships to parents (Berman 2015, 2018), as did adult children talking about their experiences in retrospective (Sigurdardóttir et al., 2018).

Only one study has focused on children’s friendships, indicating that most children were happy about neighbourhood friendships (Prazen et al., 2011). However, there is a potential for bias, as parents were present during the interviews, potentially affecting what children felt they were able to reveal in the interviews.

A review of ten qualitative studies based on interviews with children suggests that the quality and flexibility of the parent–child relationship and contextual factors relating to the children’s relationships with both parents influence how children perceive dual-residence arrangements (Birnbaum & Saini, 2015). Other studies conclude that the possibility to have a say regarding their living arrangements, and thus their situation, is something that children value (Berman, 2018; Campo et al., 2012; Haugen, 2010). Altogether, the results of the studies on children’s views and experiences suggest that children are more likely to feel positive when dual-residence arrangements are flexible and child-focused, when parents are able to cooperate and when they have influence on the details of their residence arrangements. Moreover, these qualitative studies highlight the parents’ abilities to prioritize the needs of the children. This includes avoiding conflicts in front of the children, both being present on occasions important to the child and allowing the child to be in contact with the other parent, regardless who they are currently staying with (Sadowski & McIntosh, 2015, 2016). Children are happy in living arrangements where parents take their views and feelings into account (Smart, 2004).

Policy and law

A substantial proportion of the studies in this sample can be categorized as policy debates and commentaries on legislation that sometimes build on literature reviews. As with some of the other themes above, this type of study has been published since the late 1980s. Some of these publications discuss the effects of legislative reforms, and are often country-specific (e.g. Australia: Kaspiew et al., 2011; Parkinson, 2018; Canada: Kruk, 2011, 2012; Sweden: Blomqvist & Heimer, 2016; UK: Harris-Short, 2010; US: Trombetta, 1989). Others debate the definitions of dual residence from a legal perspective and the difficulties in applying equality of time spent with parents as the sole factor in deciding living arrangements (Harris-Short, 2010; Sigurdardóttir et al., 2018). The common denominator for studies in this category is that they rely on secondary sources and court cases, sometimes lacking information on how these were chosen. While these may be of high value in terms of country-specific development, the outcome is context-based and thus difficult to compare in a global perspective.

Discussion

Taking the topic as a whole, our current knowledge is based on slightly more than hundred studies exploring the issue of dual residence for children, published over a 35-year period – a time during which many political and legislative changes have taken place. The aim of this review was twofold; to analyse the research field during this period in terms of when, where, how and by whom the research has been conducted, as well as to identify current knowledge and knowledge gaps.

Since the first studies were published more than 30 years ago, the knowledge base about children in dual-residence arrangements has grown considerably. In general, children living in nuclear families are better off in a number of health-related aspects. However, if parents separate, children appear to profit from dual-residence arrangements (regardless of the definition) if they are of the cooperative, communicative, low-conflict and non-violent type and the children are above the age of four. (When it comes to children below the age of four, research is yet too scarce to draw any conclusions.) Many studies have shown that children in dual-residence arrangements report better well-being and mental health than children who live mostly or only with one parent. Some qualitative studies suggest that certain core conditions, such as division of responsibility, parents’ cooperation, family communication, need to be in place for a beneficial outcome for children, while others argue for similar conditions but do not put it as a prerequisite. Research based on interviews with children are align that it is crucial that parents give priority to their children’s well-being over their own needs and interests and that parents are able to communicate and exchange information regarding children’s daily life. Additional positives are geographic closeness to both homes and inclusion of the children’s perspectives in the living arrangements.

While the findings from this review point to positive outcomes for dual-residence children in general, we must be careful not to apply group-based results to individual cases mechanically. Some of the qualitative studies have highlighted how specific conditions interplay with the way dual residence is experienced by children. Interviews with children who have grown up in dual-residence arrangements make clear that an arrangement that suits every child does not exist. Thus, it seems like there is no one-size-fits-all solution to resort to when it comes to prescribing the best possible living arrangement for children post-divorce.

Before we move on to discuss the development of the research field, we will consider some knowledge gaps that have been identified in the literature. Hitherto, many studies on dual residence are based on psychological theories and perspectives. In this regard, more sociologically oriented studies could contribute with tools suited for analysing aspects beyond individuals, taking into account cultural views and understandings of post-divorce arrangements and family structure. Studies considering interpersonal relationships as well as emotional and geographical mobility, particularly from children’s viewpoints, could also further our knowledge.

So far, nearly all empirical studies on dual residence have had a cross-sectional design, not allowing for examining potentially causal relationships. Studying the relationship between living arrangements and children’s well-being is a complex task, because there might be many unknown factors behind decisions about living arrangements. With longitudinal studies, it would be possible to account for such potential pre-separation differences, as well as changes over time. More broadly, research is also needed to study potential selection effects, as current research point out that parents of children in dual-residence arrangements differ in several significant ways from the majority of separated parents. None of the studies discuss in any depth whether the choice is a result of socio-demographic differences, or that dual-residence arrangements could be related to class; a question that merits further research.

Furthermore, studies are needed that particularly investigate the situation of special groups of children, such as children exposed to, for example, parental acrimony or mental illness, and children with special needs. To conclude, while the growing research base has significantly increased our understanding of many aspects of children’s dual-residence arrangements around the globe, our knowledge is still rather limited and more studies to further deepen our knowledge will be needed.

Let us now turn to the development of the research field during the 35-year period included in this review. As previously stated, there have been many political and legislative changes taking place during this time. In many countries, these changes have ‘normalized’ dual residence after divorce or separation. However, the results are highly country-specific, given the fact that policy and legislation differ widely, both currently and historically. In addition, the cultural context differs between countries in, for example, the perception of family, divorce, parenting, childhood and gender equality, as well as the prevalence of dual residence. Studies included in this review, for example, originate from countries where the degree of father involvement both prior to and after separation differs significantly, from countries where parental leave is reserved for mothers to countries where it is gender neutral and parents are encouraged to share parental leave equally. Accordingly, this includes countries where dual residence is approaching the norm (such as Sweden) and those where it is an unusual practice (such as the UK) (Fransson et al., 2018; Haux et al., 2017). An important result of this review is the need to reflect on what impact these differences have on the results of the studies, and whether findings from one context are valid for other countries or regions where the phenomenon of dual residence has been perceived differently and thus differs in praxis. In addition, as studies have found father – child ties to be stronger in dual-residence arrangements, we need to consider if this is related to gender-neutral legislation regarding parental leave and, thus, make dual residence a more suitable arrangement in those countries or if it is the arrangement itself that creates stronger ties.

One of the main findings of the current study is the great variation in the definition of dual-residence arrangements. Not having an agreed upon definition makes comparisons of results difficult at best and was also an initial methodological challenge for the present literature review. For example, while a 75/25 residence arrangement is considered as dual residence in one study, the very same 75/25 split would be categorized as sole parenting in another only counting 60/40 or even 50/50 as dual residence. This variability may be limiting but can be handled in academic exercises. However, drawing practical conclusions without considering the definition used in different studies may be comparing apples and oranges. Weekend visits only compared to sharing full weeks every other week may impact the outcome of the dual residence arrangement. Thus, we must ask if the outcome of dual-residence arrangement in a given study is related or not to the time split or if other aspects of dual-residence arrangements are more important and even case-specific. Also, as mentioned above, assessing dual residence time split depends a lot upon parental involvement pre-divorce, which may be culture, generation and relation-specific.

In the light of the results of this study, it can be concluded that research on the topic has much progressed since the first-generation studies and reached several important conclusions. The fact that it is geographically restricted and heterogeneous in terms of disciplinary perspectives, the choice of aspects to investigate, methodology, data and research design is both a blessing and a burden, as it broadens the knowledge while at the same time making comparisons more complex. What particularly complicates cross-country comparisons is the use of dissimilar terms and definitions and the diverse cultural, demographic and jurisdictional contexts of the studies. Consequently, this paper points out the complexity in using the cumulative body of research in the field when drawing conclusions and making recommendations for local practice.

The insights gained from this review study calls for further discussions regarding its implications. First of all, continued efforts are needed to make research and knowledge-based discussion the basis for policy and practice. When research is used to inform decisions for policy and practice, we particularly stress the need for reflection when seeking to apply studies onto other national contexts, and the necessity to reflect on contextual aspects such as the perception of family, divorce and parenting. Furthermore, it is useful to keep in mind when and where studies were conducted and what definitions were used.

As was mentioned in the introduction of the paper, children’s changing living arrangements post-divorce has gained great public interest as well as a large amount of attention among practitioners and policymakers. The potential benefits or risks of dual-residence arrangements has been an intensely debated issue, not seldom referring to research without paying attention to the context of the research, sometimes even using it in an inaccurate way. Existing research does not give evidence that dual residence is the best post-divorce arrangement for (all) children, nor does it show that dual residence is harmful for young children. What the research does assure us is that dual residence is a great arrangement for many children, when their needs are in focus, and when certain conditions are met.

Another central issue when applying research findings is the challenge of transmitting group-based knowledge to the individual case. When decisions about children’s living arrangements are made, it will always be necessary to consider the situation of the individual child and its family. The process following divorce differs between countries, as does the need for service improvements. Nonetheless, we suggest that resources are made available to ensure that divorcing families get their needs met. Counselling should be offered to all parents, including information and guidance about different arrangements and what conditions benefit children. Also, analysing the situation of each family and evaluating the child’s needs (including the views of the child) is essential to ensure children’s welfare. The main purpose of all involved – policymakers, professionals and parents – should be to find the best solution for every single child.

This study is offered as a resource for those interested in dual-residence arrangements in both research and practice; for professionals, children and parents. Hopefully, it can also serve as a useful resource for policy-making.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1 We do not differentiate between divorce and separation, since only some of the reviewed articles did so. In the EU, the average proportion of births outside marriage was 42% in 2014, although the level differs greatly between the EU states (Eurostat, 2017). The large number of children born to non-married parents indicates new patterns of family formation, and makes it relevant to include both separation and divorce.

2 Depending on geographical location and what definition is adopted.

3 Periodicals Archive Online, PsycARTICLES, PsycINFO, International Bibliography of the Social Sciences (IBSS), Politics Collection, Social Science Database, Sociology Database, Sociology Collection, Applied Social Sciences Index & Abstracts (ASSIA), PAIS Index, Worldwide Political Science Abstracts, Social Services Abstracts, Sociological Abstracts, ERIC, Scopus and Web of Science.