In the literature interactions with peers and friendships are considered important for the social and emotional development of children (Hartup, 1996). Children with satisfying peer relationships are more socially competent and achieve better at school (Ladd, Kochenderfer, & Coleman, 1996). Children who withdraw from social contacts are seen as deprived of social learning opportunities (Renshaw & Brown, 1993), which may cause problems at a later age (Kochenderfer & Ladd, 1996). Within the group of withdrawn children, Coplan, Rubin, Fox, Calkins, and Steward (1994) distinguish three subtypes: solitary-passive, children who like to play alone, solitary-active, children who are rejected and isolated by their peers because of their sometimes aggressive, acting-out behavior, and reticent, socially anxious children, who are afraid of making contact with their classmates (Cheah, Rubin, Fox, & Calkins, 1996) and suffer from what Asendorpf (1990) called an “approach-avoidance” conflict (see also Harrist, Zaia, Bates, Dodge, & Pettit, 1997).

Schlenker and Leary (1982) describe social anxiety as the fear of negative evaluation in social situations. It appears that the incidence of social anxiety is high (Meijers, 1978), even at a very young age, and leads to a negative self-image (Olweus, 1993). Bokhorst, Goossens, Camodeca, Stegge, and de Ruyter, (1999) demonstrated that socially anxious pupils (aged 11) suffered from a lower self-esteem and higher depression than their peers. In another study with 9 to 12-year-old children in elementary school Bokhorst, Goossens, and de Ruyter (1995) used a teacher questionnaire (Teacher Rating Scale of Social Anxiety-Senior) in addition to a self-report measure (SAS-K; Dekking, 1983). This TRSA-Senior correlated significantly with the self-report measure of social anxiety. The TRSA-Senior served as the basis for the present authors’ junior version. As there is still a shortage of instruments for the behavioral description of preschoolers, who cannot yet report reliably about themselves, they opted for the use of the teachers’ questionnaire on the grounds of its cost-effectiveness. In this paper, data about the internal consistency and the test-retest reliability of this TRSA-Junior are presented first.

Researchers interested in children’s behavior can make use of three different types of informants: teachers, peers, and observers. Measures obtained from these informants possess differing methodological strengths and weaknesses. Since the TRSA-Junior is to be filled out by teachers, the authors decided to rely on peers and observers for validation. Observations have the advantage of objectivity, but the disadvantage of being labor-intensive and usually limited to some samples of behavior. According to Coplan et al. (1994) socially anxious children avoid contact with peers. The authors opted for observations during recess, because there the observers would be less obviously visible than within the confines of the classroom (Boulton, 1999). Also, the schoolyard tends to be the place where interactions between peers take place most spontaneously. They expected socially anxious children to be less competent in their exchanges with peers (cf. also Rubin & Clark, 1983).

Young children have been depicted as poor informants about some types of behavior, because of a lack of skills (Younger, Schwarzman, & Ledingham, 1985). However, they would appear to be capable of expressing likes and dislikes. These preferences have been found to be stable and to be predictably related to behaviors reported by teachers (Asher, Singleton, Tinsley, & Hymel, 1979; Rubin & Clark, 1983). Thus, children with externalizing behaviors are usually disliked, while those with prosocial behavior are usually liked from very early on. Withdrawn children usually take up an intermediate position (Graham & Hoehn, 1995). They are neither strongly liked nor disliked. In the second study the authors correlated teacher judgments as in the TRSA-Junior with sociometric ratings (Asher et al., 1979). Teachers are usually sophisticated judges of children’s behaviors. They spend a lot of time with them, have plenty of opportunity to see the children in a variety of contexts and are usually well trained for assessing the behavior of children in their care (Ladd & Profilet, 1996). In order to further validate teachers’ assessments in the TRSA-Junior, they were asked to fill in the Behavioral Questionnaire for Toddlers and Preschoolers (BQTP; Goossens, Dekker, Bruinsma, & de Ruyter, 2001) and the Child Behavior Checklist (Achenbach & Edelbrock, 1986). The BQTP is designed to assess anxious/withdrawn behavior and aggressive/disturbing behavior, and has been well validated in The Netherlands. The CBCL is a well known, well standardized, and well validated questionnaire for mapping problem behavior in children. The BQTP and the CBCL were used to further study the convergent and divergent validity of the TRSA-Junior.

Teacher Rating Scale of Social Anxiety. The Teacher Rating Scale of Social Anxiety (TRSA) is a Likert-type teacher questionnaire of 10 items, aimed at identifying social anxiety. An example of an item is: When he/she is asked to say something in front of the class he/she is ...absolutely not afraid, not afraid, just as afraid as the other children, afraid, very afraid. A higher score indicates more social anxiety. Psychometric data are presented in the results paragraph.

Behavioral Questionnaire for Toddlers and Preschoolers. The Behavioral Questionnaire for Toddlers and Preschoolers (BQTP) is designed to measure problem behavior in young children (2-6 years). About half of the questionnaire consists of items from the Preschool Behavior Questionnaire (Behar & Stringfield, 1974). Other items were collected from teachers in preschools and daycare centers to bring the total number of items to 41. Reliability and validity of the questionnaire have been established in a variety of studies involving over 1,100 children (Goossens et al., 2001). The last item Do you think that this child has behavior problems? (answers: absolutely not, hardly, just some, many, very many) is meant to reflect a total impression. Factor analysis of the total questionnaire, with the exception of this last item, showed a clear two-factor structure: “aggressive/disruptive” and “anxious/withdrawn” behavior. An example of an item of the first scale is: Kicks or hits other children, with alternative responses from (1) absolutely not characteristic to (4) very characteristic. An example of an item of the second scale is: ...is rather on his own, with the same alternative responses.

At T1 Cronbach’s alpha for “aggressive/disruptive” behavior was .94 (item-total correlations .45 to .83). For “anxious/withdrawn” behavior reliability was .83 (item-total correlations .42 to .64). At T3 the same factors were found as at T1. Cronbach’s alpha for “aggressive/disruptive” behavior was now .91 (item-total correlations .36 to .79). For “anxious/withdrawn” behavior reliability was .87 (item-total correlations .51 to .71). Because of a relatively strong, positively skewed partition scores on both moments were transformed by extracting their root values.

Child Behavior Check List. The Child Behavior Check List (CBCL) was designed by Achenbach and Edelbrock (1986) to measure skills and problem behavior in 4- to 16-year-old children. The authors used the Dutch version of the TRF (Teacher’s Report Form). From this questionnaire they analyzed the section on problem behavior, which consists of 113 items with scores on a 3-point response scale (does not apply, applies sometimes, certainly applies). The CBCL consists of the following subscales: aggressive behavior, withdrawn behavior, somatic complaints, anxious-depressed, social problems, thought problems, attention problems and delinquent behavior. On the basis of these subscales two broad-band syndromes are distinguished: externalizing and internalizing. The CBCL is an extensively studied, reliable, and valid instrument (Verhulst, Koot, Akkerhuis & Veerman, 1990).

Observations of social participation. At T2 children were observed during recess using the scale, developed by Parten (1932; Bakeman & Brownlee, 1980; Smith, 1978), which distinguishes between 5 levels of increasing social participation: (1) unoccupied or onlooking (subsumed together by the present authors), (2) solitary play, (3) parallel play (the child plays near others and performs the same activities), (4) associative play (situations of deliberation or attempts to do so/contact with one or more other children without a common goal or structure). Included here were rough-and-tumble-play (contact in some playful or aggressive way) and (5) cooperative play (some common agreements are made). To these categories was added a sixth: aggressive behavior (actions intended to hurt another by physical force, humiliation, or insulting).

Each child was followed continuously during one minute each time over a period of 4 months and for a total number of 5 minutes (“focal subject sampling”; Pellegrini, 1996). Assignment to observations occurred at random. Observers registered both onset and termination of 1 of the 6 designated behaviors. Four observers were trained until the interobserver reliability was high (all rs > .80). All interobserver agreements were subsequently reassessed. These ran from .73 for “associative play” to .98 for “cooperative play”. “Aggression” (6) occurred infrequently and was deleted. An average score was computed (AVER-OBS) on the remaining ranked Parten scores (“unoccupied/onlooking” = 1, “solitary” = 2, “parallel play” = 3, “associative play” = 4, and “cooperative play” = 5). For example: a child who was observed for one minute in category 1, 30 seconds in category 2, 90 seconds in category 3, 60 seconds in category 4, and 60 seconds in category 5 received a total score of (60 × 1) + (30 × 2) + (90 × 3) + (60 × 4) + (60 × 5) = 930. This score was divided by the total number of seconds (300), so that the final score for this child was 3.1.

The consistency of the observations was checked by comparing the total scores for each minute with the overall score for the five minutes. Correlations ranged from .50 to .59, indicating a reasonable degree of consistency.

The TRSA was scaled optimally by means of a multi-dimensional scaling technique (HOMALS). One item was left out because of a low discriminant value (< .25). Factor analysis showed the same results. Cronbach’s alpha at T1 was: .90 (all item-total correlations were .46 or more). The average total-score was 22.5 (SD = 5.7; range 10-34). There were no gender differences (t = -1.43; ns; two-tailed). At T3 alpha was .90 (all item-total correlations were .48 or more). The average score was now: 21.7 (SD = 5.59; range 9-34). Girls scored significantly lower this time than boys (t = -2.65; p = .01; two-tailed).

The test-retest stability of the TRSA was .48; it was .56 for the girls and .41for the boys (p = .00 throughout).

The TRSA scores correlated negatively with the average score of social participation at both times. The correlation of the TRSA at T1 with AVEROBS was -.16 (p = .02) and of the TRSA at T3 with AVEROBS -.18 (p = .01). Both times a modest negative correlation was found between the level of social anxiety according to the teachers, and the level of social participation during recess. At T1 the TRSA correlated positively with the observation category “solitary” (r = .16; p = .02) and at both times negatively with the category “cooperative” (at T1: r = -.15; p = .02 and at T3: r = -.14; p = .04). In addition, the means of the TRSA scores were computed at T1 and at T3. The correlation of this mean score was -.19 (p < .05) with AVEROBS and -.19 (p < .05) with the category “cooperative”. While these correlations are modest, they do establish a fairly consistent correlation between teachers’ views of children’s social anxiety in the classroom and a low level of social participation during recess. It is important to note that there was a six-month interval between T1 and T2 as well as between T2 and T3. There was a strong correlation between the TRSA score and the “anxious/withdrawn” scale of the BQTP. At T1 this correlation was .57 (p < .001) and at T3 it was .69 (p < .001). The TRSA showed no significant correlation with the “aggressive/disruptive” scale of the BQTP (at T1 the correlation was -.01 (ns), and at T3 it was -.06 (ns)).

The correlations of the TRSA with the subscales of the CBCL are shown in Table 1. The TRSA correlates positively with the subscales withdrawn behavior, anxious-depressed, social problems, thought problems, and the broad-band syndrome internalizing, and negatively with the subscales aggressive behavior and delinquent behavior.

Thus, the data support the validity of the TRSA scale by way of modest correlations with degree of social participation during recess. Correlations with other teacher ratings (BQTP at T1 and T3; CBCL at T3) indicate more strongly the anxious and withdrawn qualities underlying the concept of social anxiety. TRSA scores do not seem to be related to externalizing qualities. However, the majority of the data in this study were supplied by teachers, about one third of whom were the same person at both times of measurement. Moreover, correlations between teacher ratings at T3 were highest, indicating that common variance caused by the fact that the same people were filling in the questionnaires may have influenced the results. This is why the authors set up study 2, in which teacher ratings were correlated with peer judgments of popularity.

Procedure and sample. In this study the sample consisted of 285 children (144 girls and 141 boys). These were nearly all children of grades 1 and 2 from four different elementary schools in small towns in the Dutch provinces of North Holland, Utrecht, and North-Brabant. The TRSA was filled in by 14 teachers who had been acquainted with their pupils about one year on average (SD = 9 months). The children’s average age was 66 months (SD = 9 months; range 49-89 months). Correlation between the TRSA–Junior and ratings by peers, collected in the following way, were investigated.

Peer ratings. The procedure of Asher et al. (1979) was used to assess the level of acceptance by classmates. Each child was given a photograph of a classmate and asked to imagine how he/she would feel if he/she were to play with this classmate. Three post boxes were put in front of the children. On these post boxes were three drawings of faces with a cheerful, a neutral, and an angry/sad expression. If the child liked playing with that classmate, he/she had to put the photograph of that child in the post box with the cheerful face. If the child did not like playing with that classmate, the photograph had to be put in the post box with the angry/sad face. If the child did not have either positive or negative feelings, the photograph had to be put in the post box with the neutral face. Each child could thus be given positive, neutral, and negative ratings. These ratings were added up per child and then divided by the number of children in the class minus one - a procedure which effectively increased the comparability of the figures across the different classrooms.

BQTP and TRSA. Again in this study teachers filled in the BQTP and the TRSA. The alpha for the “aggressive/disruptive” scale of the BQTP was .93 (item-total correlations > .46), while that of the “anxious/withdrawn” scale was: .87 (item-total correlations > .46).

Teachers appear to be able to judge their pupils consistently with a brief Likert-type questionnaire such as the TRSA-“junior”. The internal consistency coefficients were high in both study 1 and study 2. Item-total coefficients also easily met conventional requirements. The test-retest reliability was satisfactory too, especially taking into account that the interval between the two times of measurement was one year. Over such relatively long periods of time coefficients of .40 to .60 are generally considered satisfactory to good. In addition, the children assessed with the TRSA–Junior were still very young; their behavior may still be subject to considerable change. Most of such test-retest coefficients presented earlier have related to judgments by peers (Moskowitz, Schwarzman, & Ledingham, 1985) or observations (Rubin, Hymel, & Mills, 1989), but here these were able to be presented on a teacher-measure basis. The test-retest coefficient was even more impressive when the same teacher filled in the TRSA at both the first and second time of measurement. Admittedly, the test-retest coefficient was lower when different teachers filled in the TRSA at the two points of time. However, even then the coefficient indicated a moderate degree of stability of the behavior as rated. It is tempting to view this result as support for the robustness of the scale. Moreover, the analyses used to examine scale homogeneity and dimensionality produced very similar findings in two studies, suggesting that these psychometric properties replicate across samples.

The validity of the TRSA–Junior was examined by studying its relationship to both conceptually similar and dissimilar measures. Without exception the TRSA bore a strong relationship to measures of the same, or closely-related, behaviors and no relation to measures of different behavior. Such a pattern is best interpreted as support for the construct validity of the TRSA “junior”. However, these relationships may be artificially high because the same teachers supplied the data for the TRSA–Junior, the BTQP, and the CBCL.

Support for the construct and predictive validity was obtained from systematic observations during recess. It was shown that children who were judged to be socially anxious by teachers on the basis of their classroom behavior displayed low levels of social involvement with their peers during recess. The correlation coefficients showing this link were moderate at best, but there may be a number of reasons for this. First, the TRSA items describe behavior in the classroom, while the observations took place on the playground. Secondly, the observations took place approximately 6 months later than the first TRSA measurement and also approximately 6 months before the second TRSA measurement. It is highly likely that both the difference in context and the difference in time have suppressed the degree of correlation. Thirdly, moderate correlation coefficients would appear to be within the expected range when looking for relationships between global judgments on questionnaires on the one hand and systematic observations on the other (Ladd & Profilet, 1996).

Peer judgments were included in this study, as peers can be conceived of as important witnesses of other children’s behavior. Here the authors sought to replicate the well-known finding that low degrees of social involvement are not facilitative of peer acceptance (Ladd & Profilet, 1996; Rubin & Clark, 1983). The data bore out this expectation, indicating that what had been perceived by the teachers in the TRSA had also been noticed by the peers. Overall, low social involvement is usually not strongly associated with peer rejection. While the socially anxious children in study 2 received few positive ratings (expected) and the highest neutral ratings (expected), they also received the highest negative ratings (unexpected). It may be that the authors’ measure of “highly socially anxious”, that is, more than 1 SD above the mean, also included children whom Rubin and Asendorpf (1993) describe as “social isolates”. These social isolates are children who are outgoing and interested in contact with peers (“high on approach and on social motivation”), but are ignored by their peers because of their inept behavior.

The authors are inclined not to pay too much attention to the result (found at T3 in study 1), that girls were less socially anxious than boys. This was found neither at T1 nor in study 2. It could be that there was some temporary increase among the boys, and/or a decrease among the girls at that particular age. On self-report measures the authors have previously found gender differences indicating that girls report more social anxiety than do boys (Bokhorst et al., 1995; Dekking, 1983).

In sum, the TRSA–Junior shows considerable promise as a tool that can be used to gather data on one particular form of behavior, that is, social anxiety. However, this is only a first attempt at validating this scale for a young age group. All instruments have their limitations and instrument development is a never-ending process. For this reason, the present authors invite colleagues to elaborate on the psychometric qualities, validity and usefulness of the instrument.

The TRSA–Junior seems to be a useful instrument in the short and middle run. However, at this point in time there are no data about the relationship between the TRSA–Junior scores and long-term behavior. Both Rubin and Clark (1983) and Asendorpf (1990) claim that social anxiety is a risk factor in the long run. The authors are at present preparing a manuscript in which that claim is tested, because they find it important to map those risks and to test what can be done to reduce the negative consequences of social anxiety (Bokhorst, Goossens, Bokhorst, Dekker, & de Ruyter, 2001).

The TRSA–Junior is a questionnaire for use by teachers. It is brief and easy to administer and can be used at a time when very few data are yet available about the children in their care, that is, at the very beginning of their elementary school career. The advantage of this instrument is that it does not take much time or effort on the part of the teacher. However, the instrument is also limited in that it aims to measure only one characteristic. For those who want a more comprehensive questionnaire, assessing numerous characteristics there are good options such as the Preschool Behavior Questionnaire (Behar & Stringfield, 1974), the Child Behavior Scale (Ladd & Profilet, 1996) or the Child Behavior Checklist (Achenbach & Edelbrock; 1986).

Achenbach, T. M., & Edelbrock, C. S. (1986). Manual for the Teacher Report Form and teacher version of the Child Behavior Profile. Burlington, VT: University of Vermont, Department of Psychiatry.

Asendorpf, J. B. (1990). Development of inhibition during childhood: Evidence for situational specificity and a two-factor model. Developmental Psychology, 26, 721-730.

Asher, S. R., Singleton, L. C., Tinsley, B. R., & Hymel, S. (1979). A reliable sociometric measure for preschool children. Developmental Psychology, 15, 443-444.

Bakeman, R., & Brownlee, J. R. (1980). The strategic use of parallel play: A sequential analysis. Child Development, 51, 873-878.

Behar, L., & Stringfield, S. (1974). A behavior rating scale for the preschool child. Developmental Psychology, 10, 601-610.

Bokhorst, J., Goossens, F. A., Bokhorst, C. L., Dekker, P. H., & de Ruyter, P. A. (2001). De relatie tussen teruggetrokken gedrag, sociometrische status en betrokkenheid bij pesten; een longitudinaal onderzoek [The relation between withdrawal, sociometric status and involvement in bullying: A longitudinal study]. Manuscript in press.

Bokhorst, J., Goossens, F. A., Camodeca, M., Stegge, H., & de Ruyter, P. A. (1999). Emoties en cognities van sociaal angstige kinderen in de bovenbouw van het basisonderwijs [Emotions and cognitions of socially withdrawn children in primary education]. Nederlands Tijdschrift voor Opvoeding, Vorming en Onderwijs, 15, 256-277.

Bokhorst, J., Goossens, F. A., & de Ruyter, P. A. (1995). Social anxiety at elementary school: The effects of a curriculum. Educational Research, 37, 87-94.

Boulton, M. (1999). Concurrent and longitudinal relations between children’s playground behavior and social preference, victimization, and bullying. Child Development, 70, 944-945.

Cheah, C. S., Rubin, K. H., Fox, N. A., & Calkins, S. (1996). Correlates of internalizing problems in preschoolers. Poster session presented at the XIVth Biennial Conference for the International Society for the Study of Behavioral Development, Quebec City, Canada.

Coplan, R. J., Rubin, K. H., Fox, N. A., Calkins, S. D., & Steward, S. L. (1994). Being alone, playing alone, and acting alone: Distinguishing among reticence and passive and active solitude in young children. Child Development, 65, 129-137.

Dekking, Y. M. (1983). SAS-K, Sociale angst schaal voor kinderen (SAS-K, Social Anxiety Scale for Children). Lisse, The Netherlands: Swets & Zeitlinger.

Goossens, F. A., Dekker, P. H., Bruinsma, C., & de Ruyter, P. A. (2001). BQTP; Behavioral Questionnaire for Toddlers and Preschoolers: Reliability and validity. Manuscript in press.

Graham, S., & Hoehn, S. (1995). Children’s understanding of aggression and withdrawal as social stigmas: An attributional analysis. Child Development, 66, 1143-1161.

Harrist, A., Zaia, A., Bates, J., Dodge, K., & Pettit, G. (1997). Subtypes of social withdrawal in early childhood: Sociometric status and social-cognitive differences across four years. Child Development, 68, 278-294.

Hartup, W. (1996). The company they keep: Friendships and their developmental significance. Child Development, 67, 1-13.

Kochenderfer, B. J., & Ladd, G. W. (1996). Peer victimization: Cause or consequence of school maladjustment? Child Development, 67, 1305-1327.

Ladd, G. W., Kochenderfer, B. J., & Coleman, C. C. (1996). Friendship quality as a predictor of young children’s early school adjustment. Child Development, 67, 1103-1118.

Ladd, G., & Profilet, S. (1996). The child behavior scale: a teacher-report measure of young children’s aggressive, withdrawn, and prosocial behaviors. Developmental Psychology, 32, 1008-1024.

Meijers, J. J. (1978). Problem-solving therapy with socially anxious children. Lisse, The Netherlands: Swets & Zeitlinger.

Moskowitz, D., Schwarzman, A., & Ledingham, J. (1985). Stability and change in aggression and withdrawal in middle childhood and early adolescence. Journal of Abnormal Psychology, 94, 30-41.

Olweus, D. (1993). Victimization by peers: Antecedents and long-term outcomes. In K. Rubin & J. Asendorpf (Eds.), Social withdrawal, inhibition, and shyness in childhood (pp. 315-341). Hillsdale, NJ: Erlbaum.

Parten, M. B. (1932). Social participation among preschool children. Journal of Abnormal and Social Psychology, 27, 243-269.

Pellegrini, A. (1996). Observing children in their natural worlds. A methodological primer. Hillsdale, NJ: Erlbaum.

Renshaw, P. D., & Brown, P. J. (1993). Loneliness in middle childhood: Concurrent and longitudinal predictors. Child Development, 64, 1271-1284.

Rubin, K. H., & Asendorpf, J. B. (1993). Social withdrawal, inhibition, and shyness in childhood: Conceptual and definitional issues. In K. Rubin & J. Asendorpf (Eds.), Social withdrawal, inhibition, and shyness in childhood (pp. 3-17). Hillsdale, NJ: Erlbaum.

Rubin, K., & Clark, M. (1983). Preschool teachers’ ratings of behavioral problems: Observational, sociometric, sociometric, and social-cognitive correlates. Journal of Abnormal Child Psychology, 11, 273-286.

Rubin, K., Hymel, S., & Mills, R. (1989). Sociability and social withdrawal in childhood: Stability and outcomes. Journal of Personality, 57, 237-255.

Schlenker, B. R., & Leary, M. R. (1982). Social anxiety and self-presentation: A conceptualization and model. Psychological Bulletin, 92, 641-669.

Smith, P. K. (1978). A longitudinal study of social participation in preschool children: Solitary and parallel play reexamined. Developmental Psychology, 14, 517-523.

Verhulst, F. C., Koot, J. M., Akkerhuis, G. W., & Veerman, J. W. (1990). Praktische handleiding voor de CBCL [Practical manual to the CBCL]. Assen/Maastricht, The Netherlands: Van Gorcum.

Younger, A. J., Schwarzman, A. E., & Ledingham, J. E. (1985). Age-related changes in children’s perceptions of aggression and withdrawal in their peers. Developmental Psychology, 21, 70-75.

Achenbach, T. M., & Edelbrock, C. S. (1986). Manual for the Teacher Report Form and teacher version of the Child Behavior Profile. Burlington, VT: University of Vermont, Department of Psychiatry.

Asendorpf, J. B. (1990). Development of inhibition during childhood: Evidence for situational specificity and a two-factor model. Developmental Psychology, 26, 721-730.

Asher, S. R., Singleton, L. C., Tinsley, B. R., & Hymel, S. (1979). A reliable sociometric measure for preschool children. Developmental Psychology, 15, 443-444.

Bakeman, R., & Brownlee, J. R. (1980). The strategic use of parallel play: A sequential analysis. Child Development, 51, 873-878.

Behar, L., & Stringfield, S. (1974). A behavior rating scale for the preschool child. Developmental Psychology, 10, 601-610.

Bokhorst, J., Goossens, F. A., Bokhorst, C. L., Dekker, P. H., & de Ruyter, P. A. (2001). De relatie tussen teruggetrokken gedrag, sociometrische status en betrokkenheid bij pesten; een longitudinaal onderzoek [The relation between withdrawal, sociometric status and involvement in bullying: A longitudinal study]. Manuscript in press.

Bokhorst, J., Goossens, F. A., Camodeca, M., Stegge, H., & de Ruyter, P. A. (1999). Emoties en cognities van sociaal angstige kinderen in de bovenbouw van het basisonderwijs [Emotions and cognitions of socially withdrawn children in primary education]. Nederlands Tijdschrift voor Opvoeding, Vorming en Onderwijs, 15, 256-277.

Bokhorst, J., Goossens, F. A., & de Ruyter, P. A. (1995). Social anxiety at elementary school: The effects of a curriculum. Educational Research, 37, 87-94.

Boulton, M. (1999). Concurrent and longitudinal relations between children’s playground behavior and social preference, victimization, and bullying. Child Development, 70, 944-945.

Cheah, C. S., Rubin, K. H., Fox, N. A., & Calkins, S. (1996). Correlates of internalizing problems in preschoolers. Poster session presented at the XIVth Biennial Conference for the International Society for the Study of Behavioral Development, Quebec City, Canada.

Coplan, R. J., Rubin, K. H., Fox, N. A., Calkins, S. D., & Steward, S. L. (1994). Being alone, playing alone, and acting alone: Distinguishing among reticence and passive and active solitude in young children. Child Development, 65, 129-137.

Dekking, Y. M. (1983). SAS-K, Sociale angst schaal voor kinderen (SAS-K, Social Anxiety Scale for Children). Lisse, The Netherlands: Swets & Zeitlinger.

Goossens, F. A., Dekker, P. H., Bruinsma, C., & de Ruyter, P. A. (2001). BQTP; Behavioral Questionnaire for Toddlers and Preschoolers: Reliability and validity. Manuscript in press.

Graham, S., & Hoehn, S. (1995). Children’s understanding of aggression and withdrawal as social stigmas: An attributional analysis. Child Development, 66, 1143-1161.

Harrist, A., Zaia, A., Bates, J., Dodge, K., & Pettit, G. (1997). Subtypes of social withdrawal in early childhood: Sociometric status and social-cognitive differences across four years. Child Development, 68, 278-294.

Hartup, W. (1996). The company they keep: Friendships and their developmental significance. Child Development, 67, 1-13.

Kochenderfer, B. J., & Ladd, G. W. (1996). Peer victimization: Cause or consequence of school maladjustment? Child Development, 67, 1305-1327.

Ladd, G. W., Kochenderfer, B. J., & Coleman, C. C. (1996). Friendship quality as a predictor of young children’s early school adjustment. Child Development, 67, 1103-1118.

Ladd, G., & Profilet, S. (1996). The child behavior scale: a teacher-report measure of young children’s aggressive, withdrawn, and prosocial behaviors. Developmental Psychology, 32, 1008-1024.

Meijers, J. J. (1978). Problem-solving therapy with socially anxious children. Lisse, The Netherlands: Swets & Zeitlinger.

Moskowitz, D., Schwarzman, A., & Ledingham, J. (1985). Stability and change in aggression and withdrawal in middle childhood and early adolescence. Journal of Abnormal Psychology, 94, 30-41.

Olweus, D. (1993). Victimization by peers: Antecedents and long-term outcomes. In K. Rubin & J. Asendorpf (Eds.), Social withdrawal, inhibition, and shyness in childhood (pp. 315-341). Hillsdale, NJ: Erlbaum.

Parten, M. B. (1932). Social participation among preschool children. Journal of Abnormal and Social Psychology, 27, 243-269.

Pellegrini, A. (1996). Observing children in their natural worlds. A methodological primer. Hillsdale, NJ: Erlbaum.

Renshaw, P. D., & Brown, P. J. (1993). Loneliness in middle childhood: Concurrent and longitudinal predictors. Child Development, 64, 1271-1284.

Rubin, K. H., & Asendorpf, J. B. (1993). Social withdrawal, inhibition, and shyness in childhood: Conceptual and definitional issues. In K. Rubin & J. Asendorpf (Eds.), Social withdrawal, inhibition, and shyness in childhood (pp. 3-17). Hillsdale, NJ: Erlbaum.

Rubin, K., & Clark, M. (1983). Preschool teachers’ ratings of behavioral problems: Observational, sociometric, sociometric, and social-cognitive correlates. Journal of Abnormal Child Psychology, 11, 273-286.

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