The list of articles was generated using Scopus database keyword searches. This enabled a more comprehensive search across a wide variety of fields. Although using the Web of Science database for analytical literature evaluations has become more common, Scopus remains the most comprehensive database, with information from more than 20,000 journals and more exclusive articles than WOS in all categories (Falagas et al., 2008). It is the world’s most extensive abstract and citation database for peer-reviewed literature (Mongeon and Paul-Hus, 2016).

This study aims to identify spatial characteristics and play support for kids from communities in the innovation literature. Especially the state of kids’ play in open areas. Therefore, a combination of phrases linked to the neighbourhood environment and children’s play was utilised to select the peer-reviewed journal publications. Books, reports, editorials, and other non-peer-reviewed publications were specifically eliminated since peer-reviewed journals are the preferred and more reliable sources of information. Peer-reviewed journal articles were personally chosen for inclusion (Donohue and Fox, 2000). Articles were only considered if they were written in English due to the broader popularity and coverage of research and the writers’ limited linguistic abilities. Articles were only taken into consideration if the whole text was accessible from the database, allowing for appropriate study and analysis. According to the subject of research, expand the scope of search keywords, and include related synonyms as much as possible. Since the number of papers on children’s play environments is relatively stable, take the results of the past 10 years, from 2013 to 2022, as the research scope. The initial results of the search were 573 papers conducted in July 2022, with the search keywords as follows:

TITLE-ABS-KEY (“outdoor” OR “green space*” OR “environment*” OR “public space” OR “natur*” OR “landscape”) AND TITLE-ABS-KEY (“play*” OR “game*”) AND TITLE-ABS-KEY (child*) AND TITLE-ABS-KEY (“neighb*rhood*” OR “residential”) AND (LIMIT-TO (SRCTYPE, “j”)) AND (LIMIT-TO (PUBSTAGE, “final”) OR LIMIT-TO (PUBSTAGE, “aip”)) AND (LIMIT-TO (DOCTYPE, “cp”) OR LIMIT-TO (DOCTYPE,“ar”) OR LIMIT-TO (DOCTYPE,“ch”) OR LIMIT-TO (DOCTYPE, “English”))

As the papers initially searched out will not all be close to the research purpose of this study, it is necessary to exclude those irrelevant papers according to the research questions using the method of PRISMA via the author’s browsing of the abstracts and full texts (see Figure 1). The screening and eligibility checks proceeded as follows: Step 1) Two duplicate returns were identified by investigating the titles and abstracts. Step 2) All derived items were checked for consistency and accuracy of the keyword search by reading through titles and abstracts. In this stage, 67 articles out of 571 were selected, and the records were superficially screened for having a thematic match with at least children’s outdoor play and in a residential neighbourhood to indicate potential eligibility and to investigate whether those records were flagged as children’s free play without the behaviours of specific sports activities and recreational facilities. Step 3) By application of inclusion criteria to read the full text, and further screened and removed ten articles that did not relate to children’s outdoor play behaviour and spatial form and three articles that did not overlap with children’s age range from 3–12 years old. Step 4) By application of exclusion criteria, exclude two articles with no empirical results. Overall, the search procedure yielded 55 papers that meet all criteria.

The inclusion criteria were:

Articles with children’s outdoor play as the core focus of the study.

The exclusion criteria were:

Only one article will be kept for reduplicated articles.

Table 1 (Articles marked with serial numbers, see Supplementary Appendix S1) displays the theories and research frameworks pertinent to children’s outdoor play used in the investigated articles. Only 14 empirical publications had a clear theoretical foundation, while 41 might be classified as a-theoretical. The majority of publications, 9 out of 14, use the affordances hypothesis from ecological perceptual psychology established by Gibson (1979). The idea of affordances may be created, perceived, employed, or shaped (Sandseter, 2009), which might perfectly capture the spirit of children’s play. Other theories, such as the theory of loose parts (Furneaux and Manaugh, 2019), place attachment (Oscilowicz et al., 2020), attention restorative theory (Gundersen et al., 2016), theory of children’s mind development (Bao et al., 2021), naturalistic intelligence (Zhang and Tamminga, 2022), and Bourdieu’s theory of practice combined with affordance theory, can examine children’s (Ergler et al., 2013). However, studying with a single theory often requires a macro-framework structure and inevitably needs more cohesive analysis. For example, in the process of parental companionship in children’s play, parents’ psychological needs are often ignored, such as their restoration to the environment and feeling of place attachment, which can affect their initiative to accompany children. And children also have different natural aesthetic needs during outdoor activities, which will put higher requirements on integrating other theories. According to the subject of the study, the majority of these ideas have fundamental applications without showing any theoretical growth or originality.

In terms of the methods used in the body of literature on children’s outdoor play (see Table 2), surveys were most frequently used (accounting for 32.73%) among the 55 articles to be conducted, which use the technical means of a questionnaire, GIS, GPS, accelerometer, and photo elicitation, followed by the interview method, accounting for 20%. The data collected from these two methods are not only for children; parents account for a large proportion. As children in the low age group have limited cognitive ability to answer all the questions, parents need to assist in the response. It can be seen from the table that, in addition to the single use of the survey method, it is also closely combined with the interview method. This is an ideal research process, from qualitative research in the early stages to obtain data to the verification process of quantitative analysis in the later stages (Gundersen et al., 2016). More than two methods account for 50% of the total.

From the tables above, the direct way to get information about children’s outdoor activities is through surveys and interviews. Children’s outdoor activities are not involved in how they have played in the past. This happens because some neighbourhoods do not have enough space for kids to play outside often (Bao et al., 2021). Although there are studies that track children’s play behaviours over time, they do not look at the historical evolution of play forms. As a comprehensive understanding of the current situation of children’s play can be obtained through the historical evolution of children’s play and interviews with parents. Therefore, it is not only necessary to conduct interviews with children but also to explore more knowledge about children’s play activities from the perspective of parents and historical documents as much as possible. It is important to use free play or structured games as a background for studying the spatial characteristics of different residential areas.

Table 3 describes the different physical environments where children were used for outdoor play in neighbourhoods. It covers all the environmental types in and around the communities of eastern and western countries. There are not only spaces covering the general residential neighbourhood (accounting for 50.9%) but also thematic spaces, such as public green spaces (14.5%), streets (14.5%), community parks (12.7%), playgrounds (5.4%), play streets (5.4%), backyards (5.4%), school neighbourhoods (3.6%), and other microscale environments (3.6%). It can be found that the natural environment and streets are the places with the highest research frequency because of their spatial characteristics and various forms, and they are also the most preferred play environments for children (Mansor et al., 2016; Oke and Middle, 2016; Oakley et al., 2021).

The game street coincides with the street space but is not classified as the same column because it is a new game mode. It refers to a project form that closes the street within a fixed duration and allows children to play to alleviate the lack of play space or for safety needs. Moreover, mediator or moderator variables affecting children’s play are also summarised in this list to clarify which physical characteristics play a role in the influencing link of children’s outdoor play. The influencing factors in some studies are not limited to one intermediate variable. Studies may be across different intermediate elements simultaneously, so the total value of the percentages is more than 100%. From the table, another part of the research directly corresponds to the influence relationship between children’s behaviour activities and the game space to identify its internal logic. But the data is often obtained from preferences through interviews or observations, without thinking about the physical form of the space in terms of categories and structured content in the games themselves, which are challenging to obtain systematically from observations. These data are needed to think from the historical perspective of the game, as the evolution of children’s play is closely related to the natural environment (Kahn et al., 2018). It has been proven that children’s games should be most common in residential areas, where kids spend more than half of their free time (Hayball et al., 2018). Therefore, starting with the activities around existing artificial facilities or spaces does not cover children’s creative and independent characteristics.

Children’s perception of the environment is vibrant, and all kinds of literature have diverse methods of obtaining children’s sensory data. This subsection summarises all children’s environmental perceptions of outdoor play activities, including the physical and spatial aspects of the environment, according to different gender groups (see Table 4). These perceptions are expressed in the form of comparisons, preferences, conditions, strengths, weaknesses, characteristics, and recommendations. In the column on the perception of the physical environment, children’s preference for natural environments (Mansor et al., 2016; Zeng and Li, 2018; Lai and Low, 2019; Yoon and Lee, 2019; Zhang and Tamminga, 2022) and children’s preference for playing games in diverse environments accounted for the highest proportion (Holloway and Pimlott-Wilson, 2018; Loebach and Gilliland, 2019; Mears et al., 2020; Zhang and Tamminga, 2022), and the rest perception of the physical environment is relatively average. In terms of gender differences, boys have more dynamic characteristics regarding field expansion needs and spatial location movement than girls (Mansor et al., 2016; Wang et al., 2017).

Children have various expectations for the geographical environment to realise their expectations for diversified game forms. They can not only participate in community planning and design but also play by empowering children to use the environmental elements in the space in their daily play activities. There have been factors of children’s lack of freedom in games. According to Casas and Corominas (2021), 67% of kids did not quite agree that they had enough freedom to do anything they wanted in their area. It is necessary to explore how to meet the needs of children to manipulate various elements in the environment as game materials. It can be seen that reorganised spaces and diverse backgrounds with natural features should be reserved in children’s play spaces. These spaces should show natural traces as much as possible, such as seasons or the passage of time, or the optimised combination of natural elements to trigger children’s game exploration activities.

With the help of parents, children can learn critical games and social skills when they play outside (Washington et al., 2019). According to the actual investigation, parents often support children’s play by accompanying them, more likely as they are concerned about the safety of their children’s outdoor games. Even in a moderate environment, parents still have inexplicable concerns (Kepper et al., 2019). Table 5 shows six ways for parents to support children’s play. From the perspective of several of these articles, playing with their child, taking children to a location to play, and optimising the setting reached the top three, accounting for 79% of the total literature involving parent support. The rest include providing material, conditional support, and others, accounting for the remaining 21%. It can be seen from the table that some papers involve more than two types of parental support approaches for their children’s outdoor play. In terms of the specific performance of the table, it implies an additional need for environmental assistance apart from the functions of children’s games. In addition to the particular space function requirements, intergenerational interaction has positive benefits. A study also found that fathers’ participation in children’s games can fully mobilise children’s enthusiasm for playing games (Gottzén and Kremer-Sadlik, 2012).

Although parents support their children’s outdoor play in various ways, satisfaction regarding support behaviours and processes has not been explored from the parent’s perspective. Previous research always placed children at the centre of our study, with parents often acting as a supporting force in their development. But the physical and mental exhaustion of parents accompanying their children should also be given attention. The natural environment could enhance parents’ restorative psychological and other functional needs by capturing their physical and psychological feelings in the outdoors (Gundersen et al., 2016). Especially in a passive state of accompaniment, there is a need to clarify parents’ individual needs in the process of accompaniment and how these needs are met. When designing the functional space for children’s games, parents’ subjective feelings or practical needs should also be considered. Therefore, factors of parents’ support that used to be overlooked should be paid attention to.

In general, the term “structured play” refers to a task-oriented activity requiring a child to follow instructions to accomplish it (Tortella et al., 2019). Structured games are often reflected in the teaching process, which is more prominent in the teaching form (Singh, 2021). Children’s cognitive, social, and motor development is affected differently by play in various situations (Fjørtoft and Sageie, 2000; Ashley, 2011). According to Bartlett (1999), play is influenced by the local environment, including how children interact with one another in that context. Children’s games can also be promoted in the natural environment. However, due to the environmental constraints of neighbourhoods and the popularity of electronic devices, people have gradually moved away from structured games like traditional ones. Fewer rule games may increase kids’ likelihood of aggressively acting (Sayer et al., 2004). The previous description has shown that children’s outdoor games are more based on facilities, needing more experiences of game control or organisation by children themselves, which will make children gradually lose the enjoyment of social features of the play. Therefore, it is necessary to strengthen the cultivation of structured games corresponding to the environment besides the teaching scope, which would let children have the experience of guidance by rules in a play space.

The structured games played in outdoor activities, often performed by traditional games, involve regional cultural research. For example, studies from Southeast Asian countries and a few European countries mentioned it (Sutton-Smith, 1998; Frost, 2010; Genggong, 2018). The relatively small portion of studies in this area may result from the regional environment and cultural differences. For example, the population density of residential areas will affect the mixed use of space. Since most structured games are characterised by intergenerational transmission, these game activities are based on the natural environment as the context, without too many auxiliary facilities. Therefore, it is vital to introduce natural elements into the space design and shift from the design process of simple geometric forms to the details of practical functions. Furthermore, the landscape dominated by the natural environment also satisfies children’s psychological preference for being close to nature. There is much potential for research to find new ways to design game environments for kids that will make their outdoor activities more fun.

Furthermore, children’s outdoor play space is limited in high-density residential communities. To rationally allocate and utilise limited neighbourhood outdoor space for children to play games requires familiarity with the types of behaviour, characteristics, and frequency of children’s games. Integrating the game process of structured games require spatial elements with corresponding spatial matching. In a rule-driven way, even if there are no artificial game facilities or venues, it can also satisfy children’s game behaviour.

The adaptable design of residential game space refers to the functional ambiguity of children’s game space, which can meet the functional needs of different groups of people to solve the problem of hard play due to limited space. The spatial function of the residential area needs to serve different groups of people, but the main service objects are children and the elderly. For example, in China’s cultural background and high-density living environment, many families rely on intergenerational assistance to take care of children (Zhang et al., 2022). Because the elderly are more relaxed at home after retirement and the young and middle-aged are busy with work, they can only rely on their grandparents to take care of their children. So how to create an environment suitable for the needs of different people in the limited outdoor space is particularly important. To define the features of outdoor play spaces for children, it is also essential to list the functional needs of other groups, such as outdoor exercise for the elderly and outdoor sports for young and middle-aged people. All of these things need to be planned and designed together. Specifically, how to efficiently combine children’s play space with other functional spaces is especially important for developing outdoor spaces in high-density residential areas. For instance, it is possible to use spatial elements as a unit to analyse the design combination method under various functional requirements, which has rarely been involved in previous studies. In addition, there are different types of children’s games. How to rationally plan and design the residential area with the natural elements and spatial features supported by different types of games and the play behaviours of children of different ages will be a subject worthy of in-depth study. Playgrounds serve not just as locations for kids to play but also as a means of fostering interpersonal communication (Oke and Middle, 2016). In other words, the facilities in the children’s playground can not only provide exclusive sports events but also form a connection or undertake in a structured way, through different equipment, to meet the needs of children’s other free forms of play, thus promoting social activities.

In previous studies on outdoor activities in residential areas, children’s movement behaviour was identified as the most important factor, followed by social and cultural factors. However, it has rarely involved how children access various elements of the outdoors. The prerequisite for children to interact with the environment is allowing as many behaviours as possible without dividing interaction types. There have been factors of children’s lack of freedom in games, as children disagreed that they had adequate freedom to do anything they wanted in their neighbourhood (Casas and Corominas, 2021). In many gated communities, the community management department is responsible for maintaining everything in the community, and the use rights of children in outdoor spaces are largely restricted. In the future, it will be necessary to explore how to meet the needs of children by using various elements in the environment as game materials. On the premise of ensuring the safety of children, reduce the amount of maintenance on material things in the community, especially for children exploring the natural environment. Thus, children’s outdoor play should be free and open, especially with a preference for natural elements and resources. Only by abandoning the design concept that only meets the visual landscape needs of adults and reducing its restrictive use for children can the nature of children’s games be satisfied. For example, children like to pick flowers, leaves, fruits, and seeds from plants to observe and participate in imaginative games. However, this kind of openness does not mean altogether abandoning management but flexible design according to the environmental characteristics and conditions of a different residential geographic feature to promote the interaction between people and nature. Accordingly, it is necessary to explore the strategy by changing the community management mode with a more resilient landscape design model, which can encourage kids to go outside and explore to help them interact with nature better.

Parents support their kids to play outside in many different ways, from keeping an eye on them to interacting with them so they can play safely. However, the previous literature did not mention why parents have different ways of support. It is worth further studying whether they are based on parents’ preferences or the limitations of physical environmental characteristics. First, we learned from the previous article that parents’ outdoor supportive behaviours could be divided into participating in interactive games and supervising. Then, the starting point of parents’ participatory play behaviour is based on the development and guidance of children’s play or their attachment to or preference for the environment. Whether the supervising-type parents provide the space characteristics and physical environment elements suitable for the social interaction between parents in the process of accompanying, there must be some reasons behind the occurrence of these two situations. For example, whether the parents’ memory attachment to the environment is caused by visual stimulation when playing with children, which promotes the parents’ pleasure or physical and mental restoration (Geografie et al., 2014; Ratcliffe and Korpela, 2016). Parents need to supervise their children when playing outside with them. They are often involved in work or family affairs and should have additional functional facilities to meet their needs. Even if there is no task at hand, the place can also provide sports and leisure facilities that parents can experience during the playing process to stimulate their potential needs. Of course, this design strategy needs to go through systematic thinking rather than intersperse and embellish the local functions of space or via a single operation with a concrete form. It is critical for functional compatibility in the design style of the shape. Because of the insufficient space in many high-density neighbourhoods, it is challenging to distribute multiple functional facilities.