Language Abilities and Peer Rejection in Kindergarten: A Mediation Analysis

ABSTRACT

Rejection by peers has devastating effects on children’s social-cognitive development. As language difficulties have been found to be one of the underlying causes of peer rejection, the present study focused on the relation between these two variables. Specifically, this study was the first to test a hypothesized model connecting children’s level of receptive vocabulary knowledge to the extent to which they are rejected by their peers, through their ability to communicate effectively. A sample of N = 135 children (aged four to six) participated in the study. Their receptive vocabulary knowledge was assessed with the Peabody Picture Vocabulary Test, the level of oral communicative competence was measured using the Nijmegen Test for Pragmatics, and peer rejection was indicated by means of a nomination procedure. Research Findings: Outcomes of mediation analyses revealed that children’s receptive vocabulary knowledge was indirectly related to peer rejection, through oral communicative competence: Poor receptive vocabulary knowledge was associated with poor oral communicative competence, which was in turn related to a higher level of peer rejection. Gender was not a significant moderator in this model. Practice or Policy: Findings suggest the need to focus both on oral communicative competence and on receptive vocabulary knowledge when addressing peer rejection in kindergarten.

The kindergarten period – in the Netherlands between the ages of four to six – is critical for children’s social, cognitive, and emotional development. When children make the transition from home to kindergarten, one of the most important challenges they encounter is building positive relationships with peers (Hay, Payne, & Chadwick, 2004). Children who are rejected by peers do not succeed in initiating and maintaining such relationships and have been found to be at risk for various types of internalizing and externalizing behavior problems (for a review, see Hay et al., 2004). For example, a study of Menting, van Lier, and Koot (2011) showed that the experience of peer rejection in kindergarten is predictive of the level of externalizing behavior in grade 4, especially in the case of boys. In addition, several studies demonstrated that rejection by peers during the kindergarten years is associated with academic adjustment, declining classroom participation, and increasing school avoidance (Buhs, Ladd, & Herald, 2006; Morris et al., 2013; for a meta-analysis, see Nakamoto & Schwartz, 2010). Because of the negative consequences of peer rejection for children’s future adaptive functioning, research into antecedents is required in order to prevent or reduce peer rejection. In previous studies, factors such as children’s gender, ethnicity, and socioeconomic status were found to predict the degree to which children were rejected by their peers (Braza et al., 2009; Hitti, Mulvey, & Killen, 2017; Huaqing & Kaiser, 2003). In fact, boys (Braza et al., 2009), minority children (Hitti et al., 2017), and children from low socioeconomic status backgrounds (Huaqing & Kaiser, 2003) have found to be at increased risk for peer rejection. These findings are useful to the extent that they help gaining insight into possible underlying causes. However, as these factors concern stable features, it is not possible to intervene in them. In contrast, studies into behavioral and cognitive differences between children as an attempt to explain peer rejection experiences have offered useful practical guidelines (Hay et al., 2004). The present study builds on this line of research by investigating how language abilities are associated with peer rejection in kindergarten.

Language is one of the most powerful means for building successful relationships with peers. It enables children to enter peer play situations, to contribute to meaningful interactions, and to communicate their own ideas (Hay et al., 2004). Previous research has shown that children who are restricted in the ability to use language in an effective manner are at increased risk for being excluded from positive peer interactions (e.g., Laws, Bates, Feuerstein, Mason-Apps, & White, 2012; Redmond, 2011). It is therefore to be expected that children’s language abilities are significantly related to the degree to which they are rejected by peers. In investigating language abilities, the current study specifically focused on receptive vocabulary knowledge and oral communicative competence. Receptive vocabulary knowledge indicates a child’s ability to understand a word when it is heard or seen (e.g., Dunn & Dunn, 2005; Zhou, 2010), and is an important component of oral communicative competence (see for example the model proposed by Celce-Murcia, 2008). The term oral communicative competence refers to the ability to use language effectively and appropriately in different social situations (Celce-Murcia, 2008; see also Samter, 2003). It is however a broad and multi-faceted concept that consists of multiple abilities. Specifically, although vocabulary knowledge is an important part of oral communicative competence, it is not sufficient for effective communication.

A model developed by Roth and Spekman (1984) is helpful in further defining the concept of oral communicative competence. This model contains three components: (1) communicative intentions, (2) presupposition, and (3) social organization of discourse. The first component concerns the intention a speaker conveys and its effect on the listener. Importantly, there is an entire range of different intentions (e.g., regulating others’ behavior) that can be either expressed directly (requiring only a literal interpretation: “Could you hand me the pencil?”) or indirectly (requiring a degree of inference: “I wish I had a pencil”). The second component refers to the ability to take the perspective of the conversational partner. Specifically, a speaker should take the perspective of the listener into account to be able to decide on the content and form of his or her message whereas a listener needs to infer the speaker’s intentions behind a message rather than relying solely on its literal meaning. The third component indicates the ability to maintain the stream of a conversation. It entails the ability to take turns, to initiate, maintain, and end a topic, and to repair communicative breakdowns (e.g., by repeating something). The three aforementioned components of Roth and Spekman’s model are all highly influenced by the communicative context (e.g., channels available for communication). In fact, it is the social context that affects the type of communicative intentions, the amount of information that needs to be provided, and the manner in which conversations are organized (Roth & Spekman, 1984; for a graphic representation of the model, see Appendix A). In the current study, we used an instrument to measure oral communicative competence, which is based on Roth and Spekman’s model.

Previous studies into the relation between language abilities and peer rejection primarily focused on receptive vocabulary knowledge, demonstrating that it is significantly associated with childhood peer rejection (e.g., Longobardi, Spataro, Frigerio, & Rescola, 2016; McCabe, 2005; Menting et al., 2011; Slaughter, Dennis, & Pritchard, 2002; Stowe, Arnold, & Ortiz, 1999). But why is this so? One possible explanation might be that oral communicative competence plays an important role in the relation between receptive vocabulary knowledge and peer rejection. Specifically, it has been suggested that children with little word knowledge are less able to interpret the intentions of others and find it harder to communicate their own ideas, needs, and emotions (Menting et al., 2011). Difficulties in communication might, in turn, result in social conflicts and rejection by peers (Astington & Jenkins, 1999; Hay et al., 2004; Mostow, Izard, Fine, & Trentacosta, 2002). This could indicate that a lack of receptive vocabulary knowledge adds to or is indicative for difficulties in oral communicative competence which then increases the risk of peer rejection. Thus far, however, no studies have investigated the relations among receptive vocabulary knowledge, oral communicative competence, and peer rejection at the same time. It therefore remains unknown whether receptive vocabulary knowledge is directly related to peer rejection (as previous research suggested), or whether this relation is actually (or partially) an indirect one, through oral communicative competence. The main purpose of the present study was to address this gap and investigate whether there is a direct relation between receptive vocabulary knowledge and peer rejection (relation a), as well as an indirect one, namely from receptive vocabulary knowledge to oral communicative competence (relation b), and from oral communicative competence to peer rejection (relation c). This hypothesized model is represented in Figure 1.

Figure 1. Hypothesized model connecting children’s level of receptive vocabulary knowledge to the extent to which they are rejected by their peers, through their ability to communicate effectively.

Although no studies have investigated the associations among receptive vocabulary knowledge, oral communicative competence, and peer rejection simultaneously, several lines of research partially support the model that was hypothesized in the present study. First, multiple studies have shown a negative association between receptive vocabulary knowledge and peer rejection (relation a). A study conducted by Menting et al. (2011), for example, showed that children with poor receptive vocabulary knowledge experienced higher levels of peer rejection, which, in turn, increased their engagement in aggressive behavior. The authors theorized that higher levels of peer rejection were due to children’s difficulties in interpreting the intentions of their peers and understanding social interactions. In addition, Stowe et al. (1999) specifically investigated gender differences in the relations among language development, disruptive behavior, and peer relationships. Outcomes revealed that children’s peer relationships were predicted by a composite measure of language skills consisting of expressive and receptive vocabulary. Moreover, Stowe et al. found that the quality of children’s peer relationships was less strongly related to vocabulary for girls than for boys. They explained this finding by indicating that boys and girls were differently influenced by their language difficulties: Boys tended to react with aggression whereas girls were more inclined to withdraw (Stowe et al., 1999). As aggressive behavior has found to be strongly related to rejection by peers (e.g., Chen, McComas, Hartman, & Symons, 2011; Menting et al., 2011; Stowe et al., 1999), this might explain why the relation between poor vocabulary and peer rejection was stronger for boys than for girls.

Second, several studies have demonstrated a significant relation between children’s receptive vocabulary knowledge and their level of oral communicative competence (relation b). Bornstein and colleagues (Bornstein & Haynes, 1998; Bornstein, Haynes, & Painter, 1998), for example, conducted a series of studies into the conceptualization of vocabulary competence in toddlerhood. Specifically, they investigated links among maternal characteristics (e.g., personality), child characteristics (e.g., gender), and language abilities. Outcomes revealed significant and positive correlations between children’s word comprehension, as measured by a standardized test, and mothers’ perceptions of their children’s communication skills (Bornstein & Haynes, 1998; Bornstein et al., 1998). In addition, a study by Milton, Wade, and Hopkins (2010) indicated that vocabulary size proves to be a good predictor of communicative ability, explaining approximately 40% of its variance. These findings indicate a relation between vocabulary competence and communicative ability and are in line with the original theory of the linguistic anthropologist Dell Hymes who claimed that oral communicative competence includes knowledge of (1) grammar and vocabulary, (2) rules of speaking, and (3) how to use and respond to different types of speech (Hymes, 1972; see also Celce-Murcia, 2008). Although Hymes’ theory of human communication was later adapted by others, the idea that vocabulary is part of, and might contribute to, oral communicative competence remained intact.

Third, a few studies revealed a significant negative correlation between oral communicative competence and peer rejection (relation c). This relation has originally been investigated by Black and colleagues in a series of qualitative studies with preschool children (Black & Hazen, 1990; Hazen & Black, 1989). Outcomes demonstrated that children’s communication skills were related to their position within the peer group: Disliked children differed from their peers by showing less responsive and more disruptive communicative behavior (Black & Hazen, 1990; Hazen & Black, 1989). In addition, results of a small-scale study by Nӕrland (2011) revealed the potential unique importance of the ability to communicate effectively for children’s popularity. Specifically, this study demonstrated that, in contrast to other measures of language abilities (i.e., a score to reflect children’s range of words available and a score of their mean length of utterances) only children’s score on communicative abilities contributed to their popularity independent of age. Findings of these small-scale, exploratory studies have been recently confirmed in a study with a large sample and standardized, quantitative measures showing that children who were less able to communicate in an effective and appropriate way, were more often rejected by peers (van der Wilt, van der Veen, van Kruistum, & van Oers, 2018). The authors argued that children with poor oral communicative competence might be less attractive playmates to their peers and, therefore, experience higher levels of peer rejection.

Taken together, separate lines of research suggest that receptive vocabulary knowledge is not only directly related to peer rejection, but might also be indirectly related to it, through oral communicative competence. This raises the following question: Is there actually a direct relation between receptive vocabulary knowledge and peer rejection, or are these two variables only related because of the relations between receptive vocabulary knowledge and oral communicative competence and between oral communicative competence and peer rejection? The aim of the present study was to address this matter and to provide new leads for interventions directed at the prevention or reduction of peer rejection. In doing so, the focus was specifically on the kindergarten period (in the Netherlands, between the ages of four to six). Compared to toddlers, four-year-olds become increasingly able to express themselves verbally which allows them to solve peer conflicts in a prosocial manner (Hay et al., 2004). Moreover, during the kindergarten period, children increasingly learn to take others’ perspective and adapt their speech and communication to the needs of others (Berk, 2009; Brooks & Kempe, 2012; Gulay, 2011). In addition, the transition to kindergarten affects children’s peer relationships. Specifically, spending an increasing amount of time in a fixed peer group (i.e., children’s own class) helps children to gradually transform their preferences for certain peers into more stable friendships, something that usually results in the establishment of relatively stable group structures (Hay et al., 2004; Parker, Rubin, Erath, Wojslawowicz, & Buskirk, 2006). Children’s rapid language development and the changes in their peer relationships made the kindergarten period a particularly interesting period for investigating the relation between language abilities and peer rejection.

To summarize, the present study hypothesized that there would be an indirect relation between receptive vocabulary knowledge and peer rejection (i.e., through oral communicative competence), and that both oral communicative competence and receptive vocabulary knowledge would be directly related to the extent to which children are rejected. In addition, we explored whether gender might moderate these relations, because some studies found differences in the relation between language abilities and peer rejection between boys and girls (e.g., Stowe et al., 1999; van der Wilt, van Kruistum, van der Veen, & van Oers, 2016). No specific assumptions were made regarding the direction of the potential effect of gender as previous research generated mixed results.

Method

Participants

Children of three elementary schools from two urban areas in the western part of the Netherlands were recruited through the personal network of the researchers. The total sample consisted of N = 135 children (including 72 boys and 63 girls) aged 4.00 to 7.08 years (M = 5.35, SD = 0.78). Children came from six different kindergarten classrooms. In the current study, each class included an average of approximately 23 children (Min = 20, Max = 24), and 100% of the children in each classroom participated. The boards of the schools from which the sample was drawn did not permit the collection of detailed information regarding child ethnicity, parental employment status, or family income. School guides, however, indicated that the participating schools are mainly visited by children who live in the neighborhood. Table 1 shows population characteristics for nationality and income of the neighborhoods in which the schools are situated (Central Bureau for Statistics, 2015, 2018).

Table 1. Socioeconomic characteristics of the neighborhoods of the three participating schools (N = 135).

	School 1	School 2	School 3
Nationalities
Western	67.8%	47.6%	27.8%
Moroccan	1.3%	14.7%	25.4%
The Netherlands Antilles	3.9%	2.3%	2.1%
Surinam	3.3%	9.4%	16.0%
Turkish	1.3%	6.7%	11.2%
Other	22.4%	19.3%	17.5%
Income
Average income per person	€29,700	€26,500	€27,600
40% persons with lowest income^a	52.2%	45.4%	34.4%
20% persons with highest income^b	27.7%	21.3%	27.3%

^apercentage of persons belonging to the national 40% with lowest personal income;

^bpercentage of persons belonging to the national 20% with highest personal income.

Procedures

The present study was part of a larger research project for which ethical approval was obtained from the Scientific and Ethical Review Board of the Faculty of Behavioral and Movement Sciences of the Vrije Universiteit Amsterdam (van der Veen, 2017). All measures were individually administered by a trained test assistant in a quiet room near the children’s own classroom. Test administrations were divided into two sessions and were spread over two consecutive schooldays. During the first session (day 1), children were tested on the Nijmegen Test for Pragmatics (Embrechts, Mugge, & van Bon, 2005). Administrations of this test took approximately 20 minutes per child and were audiotaped in order to score them afterwards. During the second session (day 2), first the Dutch version of the Peabody Picture Vocabulary Test (Schlichting, 2005) was administered and then a peer nomination procedure (e.g., Menting et al., 2011) was conducted. These two measures were presented in a fixed order and were scored directly. The second session lasted about 15 minutes. Hence, total child participation took approximately 35 minutes per child.

Measures

Receptive Vocabulary Knowledge

Receptive vocabulary knowledge was assessed using the Dutch version of the Peabody Picture Vocabulary Test, third edition (Schlichting, 2005). This test is a standardized task designed to measure receptive vocabulary (Dunn & Dunn, 1997). It entails a picture book with 204 items (17 sets of 12 items), each containing four black-and-white line drawings. Participants are asked to indicate which picture displays the word that is read aloud by the test assistant. For example, one item goes as follows: “Could you point to the picture of a person who is laughing?” In this case, participants can choose among pictures of a person who is crying, who is drinking tea, who is looking shocked, and who is laughing. The test starts with common concrete objects (e.g., hand) or simple actions (e.g., jumping) and becomes increasingly difficult such that the last sets of items contain uncommon objects (e.g., gable roof) or abstract concepts (e.g., lament). The starting set depends on the participant’s age. If the participant has more than four errors in the starting set, then the test assistant moves to the previous set. A basal set is established when the participant makes no more than four errors in the set. After establishing a basal set, the test assistant continues the test until the participant makes nine or more errors in a set, establishing the ceiling set for this participant. In the present study, a raw score was calculated by subtracting the total number of errors from the total number of completed items. Subsequently, a standardized score, the Word Comprehension Quotient, was obtained using a table providing age-corrected normative scores. Previous research into the reliability of the test has indicated that its internal consistency is good (average Guttman’s Lambda-2 coefficient of .93 for children aged four to seven years; Schlichting, 2005).

Oral Communicative Competence

Oral communicative competence was measured with the Nijmegen Test for Pragmatics (Embrechts et al., 2005), a standardized and validated test designed to assess the pragmatic competence (a concept very similar to oral communicative competence) of children in the age of four to seven years. The test consists of three subscales: Communicative Functions, Conversation Skills, and Story Building. Administration of the complete Nijmegen Test for Pragmatics is quite long (i.e., approximately 45–60 minutes). In addition, the subscale Story Building was considered less important for measuring oral communicative competence, because it assesses the ability to tell a coherent story in the form of a monologue, without reference to a conversational partner. In the current study, therefore, only the two subscales Communicative Functions and Conversation Skills were used. During the test administration, the participating child is shown a two-dimensional toy house with nine small windows that can be opened. Behind the windows, nine different rooms can be found that are also visible on large color pictures. The test assistant guides the participating child through the different rooms by telling a story about the daily life of the two children living in the toy house, Peter and Lotje. In the present study, the test assistant read the 37 items of the two subscales aloud in order to tell the story. For example: “Lotje sees a big spider and wants her mom to look at it. What does Lotje say?” In this case, children needed to take the perspective of Lotje into account and were required to draw the attention of Lotje’s mom. Children’s answers were scored dichotomously (right answer = 1, wrong answer = 0). In case of the previous example, one point was assigned to “Mom!” or “Mom, look at that spider!” whereas “Lotje wears a hat” or “That is a spider” resulted in zero points. The total score on oral communicative competence was calculated by summing the number of correct answers. Internal consistency of the scales used in the current study was strong (Omega = .88, GLB = .93, Cronbach’s alpha = .88).

Peer Rejection

A sociometric method with a peer nomination procedure was used to indicate children’s position within their peer group (see for example Gifford-Smith & Brownell, 2003), though the procedure was slightly adapted in order to suit children’s young age. Specifically, children first participated in an orientation activity in which they were shown pictures of various types of food and were asked to indicate which types they liked and which not. Since this task simulated the actual sociometric task, children could practice with nominating and indicating their preferences. After this orientation task, children were shown pictures of all their classmates. To ensure that they would pay attention to each of them, they were asked to name each of their classmates. Next, the following question was posed: “With whom do you like to play?” This question was asked three times and resulted in three positive nominations. A second question followed: “With whom do you not like to play?” Again, this question was asked three times, so three negative nominations were obtained. In the end, children had nominated six classmates: three positively and three negatively. To diminish the chance that children would discuss their peer nominations with each other, after the sociometric task children were shown pictures of several types of toys and were asked which types they liked and which not. For each child, the amount of received positive nominations and negative nominations was counted separately, resulting in a positive nomination score and a negative nomination score. To control for differences in classroom size, the positive and negative nomination scores were standardized within classrooms. The level of peer rejection was obtained by subtracting the standardized positive nomination scores from the standardized negative nomination scores (see also Menting et al., 2011). The nomination procedure has proved to be a reliable and valid method to indicate a child’s level of peer rejection in kindergarten (Keane & Calkins, 2004; Wu, Hart, Draper, & Olsen, 2001).

Analyses

Statistical analyses were conducted using Statistical Package for the Social Sciences (version 23). Complete data were available for the Peabody Picture Vocabulary Test and the peer nomination procedure, but 7% of the data were missing with regard to the Nijmegen Test for Pragmatics (due to the absence of children (e.g., because of illness) on the day of testing). Missing data were imputed using the commonly used Expectation-Maximization (EM) method in SPSS after finding no statistically significant deviation from randomness (Little’s MCAR test, X²(2) = 1.60, p = .450). The imputed dataset was used in subsequent analyses.

Since the variance in the level of peer rejection between classes was very small (i.e., σ²_classes = 0.02) it was unnecessary to apply multilevel modelling (Peugh, 2010). In addition, although Shapiro-Wilk tests showed that scores on receptive vocabulary knowledge (p = .001) and oral communicative competence (p < .001) did not follow a normal distribution, the data on peer rejection, the dependent variable, was normally distributed (p = .162). Because multilevel modelling was not required and the assumption of normality was met for the dependent variable, the hypothesized model could be assessed by means of the PROCESS macro developed for SPSS (Hayes, 2013). PROCESS is a computational tool for path analysis-based moderation and mediation analysis as well as their integration in the form of a conditional process model (e.g., a moderated mediation model). The tool provides estimates of indirect effects with bias-corrected bootstrap confidence intervals. The bootstrap method is preferred over other methods in assessing the existence of mediation among variables, because it repeatedly draws samples from the data, estimating the indirect effect with each resampled data set. In the present study, the recommendation of Hair, Hult, Ringle, and Sarstedt (2014) was followed and bootstrapping was set to the default level of 5000 resamples.

Results

Preliminary Analyses

In Table 2, the means and standard deviations of each main variable are displayed. Although standardized scores on peer rejection were used in subsequent analyses, unstandardized scores are provided to facilitate the interpretation of the mean scores. In addition, Table 2 incorporates Pearson product-moment correlations (r), indicating associations among the main research variables, and the results of independent samples t-tests, to examine gender differences. Outcomes of the correlation analyses demonstrated a significant positive correlation between receptive vocabulary knowledge and oral communicative competence: Children with high levels of receptive vocabulary knowledge showed high levels of oral communicative competence as well. In addition, oral communicative competence was significantly and negatively related to peer rejection: Children with a lower level of oral communicative competence were more likely to be rejected by their peers. Finally, oral communicative competence was significantly and positively correlated with age: With age, children exhibited higher levels of oral communicative competence. Regarding the independent samples t-tests, outcomes indicated that boys and girls significantly differed with respect to their level of oral communicative competence: Boys exhibited lower levels than girls.

Table 2. Descriptive statistics, correlations and gender differences for the main variables (N = 135).

		Mean (SD)			Correlations (r)
	Variable	Total	Boys	Girls	1	2	3	4	Gender (t)
1	Receptive vocabulary knowledge	105.99 (18.91)	105.18 20.49	106.92 (17.05)		.47***	−.14	−.14	−0.53
2	Oral communicative competence	27.32 (6.63)	26.15 (7.16)	28.66 (5.72)			−.21*	.40***	−2.22*
3	Peer rejection	−0.14 (3.29)	0.00 (3.41)	−0.30 (3.17)				−.16	0.53
4	Age	4.35 (0.78)	5.38 (0.79)	5.31 (0.76)					0.50

*p ≤ .05; **p ≤ .01; ***p ≤ .001

Testing the Hypothesized Model

Although correlational analyses indicated that receptive vocabulary knowledge was not related to peer rejection, the two variables might be indirectly related (i.e., through oral communicative competence). In order to assess whether such an indirect relation exists, a simple mediation analysis (Hayes, 2013) was performed. As preliminary analyses indicated that age and gender were significantly related to oral communicative competence, they were both included in the mediation analysis as covariates. Results of this analysis are displayed in Table 3. In line with the outcomes of correlational analyses, findings of the mediation analysis indicated that receptive vocabulary knowledge was not significantly related to peer rejection (a = − 0.005), but did significantly correlate with oral communicative competence (b = 0.188, small effect): Children with low levels of receptive vocabulary knowledge also exhibited low levels of oral communicative competence. Oral communicative competence was, in turn, directly related to peer rejection: Children with low levels of oral communicative competence were more likely to be rejected by their peers (c = − 0.047, small effect). Finally, the absence of zero in the confidence interval for the indirect pathway indicated that the indirect effect of receptive vocabulary knowledge on peer rejection (through oral communicative competence) was significant as well (B = − 0.009, SE = 0.004, 95% confidence interval = [−0.019 to 01.001]). Thus, oral communicative competence was found to have a direct relation with peer rejection whereas receptive vocabulary knowledge was only indirectly related to it (Figure 2). The complete model was significant and explained 5.6% of the variance in peer rejection.

Figure 2. Model demonstrating a direct effect of oral communicative competence on peer rejection and an indirect effect of receptive vocabulary knowledge on peer rejection, through oral communicative competence (N = 135).

Table 3. Effects of receptive vocabulary knowledge and oral communicative competence on peer rejection (N = 135; bootstrap resamples = 5000; unstandardized coefficients).

		Peer rejection				Oral communicative competence
		B	SE	p		B	SE	p
Receptive vocabulary knowledge	a	−0.005	0.008	.504	b	0.188	0.023	< .001
Oral communicative competence	c	−0.047	0.022	.039
Age						4.042	0.561	< .001
Constant	i1	1.827	0.774	.020	i2	−14.194	4.137	.001
		R^2^=0.056				R^2^=0.442
		F (2, 132) = 3.935, p = .022				F (2, 132) = 52.244, p < .001

Preliminary analyses into possible gender differences indicated that boys and girls did not differ in their level of receptive vocabulary knowledge or in the extent to which they were rejected by peers. However, this does not indicate whether gender differences exist in the relations among the main variables. To examine gender as a potential moderator of the relations among receptive vocabulary knowledge, oral communicative competence, and peer rejection, a moderated mediation analysis was conducted in accordance with the procedures of Hayes (2013). This analysis revealed no significant findings, F (5, 129) = 1.44, p = .214, suggesting that gender was not a significant moderator in the model. Therefore, this model was not further explored.

Discussion

The purpose of the current study was to investigate the link between language abilities and peer relationships in kindergarten. More specifically, this study was the first to test a hypothesized mediation model connecting children’s level of receptive vocabulary knowledge to the extent to which they are rejected by their peers, through their ability to communicate effectively. Contrary to the formulated hypothesis, no evidence was found for a pathway linking receptive vocabulary knowledge directly to peer rejection. Instead, receptive vocabulary knowledge only had an indirect effect on peer rejection, namely through oral communicative competence. These outcomes underline the importance of taking oral communicative competence into account in examining peer rejection in kindergarten.

In discussing the outcomes, we will first consider the findings that coincide with those of previous research. The outcome that receptive vocabulary knowledge was directly related to oral communicative competence is in line with findings of prior studies in which such an association was found (e.g., Bornstein et al., 1998; Milton et al., 2010). This seems to confirm that oral communicative competence is a complex and multifaceted construct that encompasses multiple sub-abilities, such as vocabulary knowledge (see Celce-Murcia, 2008). Moreover, this also suggests that different aspects of language proficiency are interrelated and that proficiency in one domain affects proficiency in another domain. In addition, the association between oral communicative competence and peer rejection that was found in the current study is also supported by outcomes of prior research (e.g., Black & Hazen, 1990; Hazen & Black, 1990; Nӕrland, 2011; van der Wilt et al., 2018). The fact that these findings are in line with findings of previous studies emphasizes the important role of children’s oral communicative competence in the context of peer relationships. Furthermore, although beyond the scope of the main research aim, both gender and age appeared to be of influence on children’s level of oral communicative competence: Girls exhibited higher levels of oral communicative competence than boys and oral communicative competence increased with age. With respect to previous research, girls are indeed often found to have superior language abilities to boys, although these gender differences gradually disappear (Wallentin, 2008). As for age, outcomes of the present study confirm the finding that language abilities develop over time (e.g., Gulay, 2011).

In the current study, we did not find a direct relation between receptive vocabulary and peer rejection. This is surprising, as several studies have found such a relation between receptive vocabulary knowledge and peer rejection (e.g., Menting et al., 2011; Slaughter et al., 2002; Stowe et al., 1999). Why was no such relation found in the present study? For the sake of brevity, not every single study is considered in order to answer the question of why a relation between the two variables was found in that particular study but not in the present one. It is important, however, to highlight the study of Menting et al. (2011), because it has many similarities with the current study: The two studies were both conducted in elementary schools in the Netherlands, used the Word Comprehension Quotients of the Peabody Picture Vocabulary Test to indicate children’s level of receptive vocabulary knowledge, and adopted roughly the same procedure to measure their degree of peer rejection. However, an important difference between the two studies is that the study of Menting et al. concerned a longitudinal design: Children were followed over a four-year-period, from kindergarten to grade 4. The outcomes of Menting et al. actually showed that, although receptive vocabulary knowledge was significantly related to peer rejection on the long run, there was no concurrent relation between receptive vocabulary knowledge and peer rejection. This seems to indicate that receptive vocabulary knowledge is important in the context of peer rejection as it predicts children’s future experience with rejection by peers, but is not as important a factor for children’s current level of rejection.

The indirect relation that was found in the present study could explain why receptive vocabulary knowledge might only be longitudinally related to peer rejection: Children with poor word knowledge might experience increasing difficulties in peer communication over time and these difficulties are, in turn, likely to be directly related to peer rejection. This explanation is in line with the ones that are provided in previous studies in which a relation was found between receptive vocabulary knowledge and peer rejection (Schneider, 2008; Slaughter et al., 2002; Stowe et al., 1999). In fact, the relation between these two variables seems to be consistently explained by referring to some other, third variable (e.g., disruptive interactions; Stowe et al., 1999). Although this still cannot explain why these studies did find a direct relation between receptive vocabulary knowledge and peer rejection, differences in the measurement and/or operationalization of peer rejection between previous studies and the present one might be able to do so (i.e., the use of best friend ratings instead of peer nominations; Schneider, 2008). However, future research is required in order to investigate exactly how these methodological differences result in different findings.

Although the present study has provided new insights with regard to the relations among receptive vocabulary knowledge, oral communicative competence, and peer rejection, the study did suffer from several limitations. First, some important background characteristics of the investigated sample were unknown. In previous research, for example, it has been suggested that it might be important to take socioeconomic status into account in investigating the link between language abilities and peer relationships (Longobardi et al., 2016). Unfortunately, such data were not available in the present study. One should therefore be careful in generalizing the results.

Second, there were some shortcomings of the Nijmegen Test for Pragmatics (Embrechts et al., 2005) that was used in the present study to measure children’s level of oral communicative competence. In particular, during the administration of this test, children interact with an unfamiliar adult in a somewhat artificial situation in which they are confronted with hypothetical dilemmas. It has been argued that competence in child-adult interaction cannot be directly converted to competence in child-child interaction (Nӕrland, 2011). In addition, it is one thing to be able to produce an adequate response to a hypothetical dilemma, but it is something else to actually enact such a response in real life settings (e.g., in a classroom context; Nӕrland, 2011; see also Roth & Spekman, 1984). Although the Nijmegen Test for Pragmatics has multiple strengths (e.g., it is a reliable, valid, and standardized test), it is important to note that the present study did not take children’s actual behavior in peer interactions into account. Hence, future research into the relation between language abilities and peer rejection could use a measure that assesses children’s communication skills within the classroom context (see for example the Conversation Compass Communication Screener-Revised, Curenton, Sims, Rochester, & Gardner, 2019; see also Gardner & Curenton, 2017).

Third, a relatively small amount of variance in peer rejection was explained by the hypothesized model. This indicates that besides language abilities, other factors are involved in the context of peer rejection. Previous research indicated that children’s peer relationships are affected by, for example, the ability to send and receive emotional signals (Dunsmore, Noguchi, Garner, Casey, & Bhullar, 2008), to act in a social manner (Gifford-Smith & Brownell, 2003), and to imitate others (Hay, Caplan, & Nash, 2009). In addition, it has been suggested that certain child characteristics, such as having a disability, affect children’s peer relationships as well (Kwon, Hong, & Jeon, 2017). Besides, not only factors that are associated with the individual child might be important; a part of the variance in peer rejection may be explainable by group characteristics. It has been shown, for example, that children who engage in aggressive behavior in groups with high levels of aggression are less likely to become rejected than children who display similar behavior in nonaggressive peer contexts (Bierman, 2004; Boor-Klip, Segers, Hendrickx, & Cillessen, 2017; Mikami, Boucher, & Humphreys, 2005; Parker et al., 2006). However, although it would be interesting to investigate in future research which other factors contribute to peer rejection, language abilities might be particularly interesting because they can be fairly easily and effectively promoted.

The present study points to the significance of oral communicative competence and, more indirectly, receptive vocabulary knowledge for peer rejection. Although previous research already indicated that receptive vocabulary knowledge is a significant predictor of peer rejection (Menting et al., 2011), further research is needed to investigate the direction of the relation between oral communicative competence and peer rejection in order to indicate whether poor communicative abilities result in peer rejection, or whether rejection by peers affects oral communicative competence, or both. Moreover, in contrast to previous tendencies, future studies should not only focus on receptive vocabulary knowledge; the present study indicates that especially oral communicative competence might play a significant role in the context of peer rejection and should therefore be taken into account. If future research can demonstrate that receptive vocabulary knowledge and oral communicative competence affect children’s degree of peer rejection (direct or indirect), then kindergarten teachers who try to prevent or reduce peer rejection should take the systematic promotion of both language abilities into account. Recent research demonstrated, however, that kindergarten teachers already pay ample attention to the promotion of children’s vocabulary (van der Veen, van Renswouw, & Pennings, in preparation). In addition, vocabulary tends to have a prominent place in current language programs (e.g., Snow & Matthews, 2017) whereas several researchers have called for an increased attention to the promotion of oral communicative competence (e.g., Mercer, 2008; Mercer, Warwick, & Ahmed, 2017; Nӕrland, 2011). Hence, if future research can demonstrate that oral communicative competence causally affects children’s level of peer rejection, kindergarten teachers might therefore be encouraged to focus more explicitly on children’s ability to communicate effectively. A recently published article shows how to promote young children’s oral communicative competence through productive classroom talk (van der Veen, van der Wilt, van Kruistum, van Oers, & Michaels, 2017; see also Michaels & O’Connor, 2012, 2015). By asking children to, for example, respond to each other’s contributions (“Could you add something to what he said?”), clarify themselves (“Does everyone understand what he means?”), and reflect on their communication (“Who remembers our conversational rules?”), teachers can establish a classroom culture in which children are stimulated to practice their communicative abilities on a daily basis.

To conclude, the results of this study showed a direct and negative relation between children’s level of oral communicative competence and their level of peer rejection: Children with low levels of oral communicative competence were more likely to be rejected by their peers. In addition, an indirect relation was found between receptive vocabulary knowledge and peer rejection, through oral communicative competence. If future research can demonstrate the causal effect of oral communicative competence on children’s level of peer rejection, kindergarten teachers can be encouraged to pay more specific attention to their pupils’ communicative abilities, above and beyond their current focus on children’s vocabulary knowledge.

Acknowledgments

The authors would like to thank Dr. Marleen de Moor for her advice in the statistical analyses, and the testassistants for helping with the data collection.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study did not receive any funding.

Appendix A. Graphic Representation of the Model of Roth and Spekman (1984).