Worry in Children

Abstract

Worry in adults has been conceptualized as a thinking process involving problem-solving attempts about anticipated negative outcomes. This process is related to, though distinct from, fear. Previous research suggested that compared to adults, children’s experience of worry is less strongly associated with thinking and more closely related to fear. The present study further explored children’s worrying. Ninety-three 7- to 12-year-olds rated how much they worry, fear and think about the same list of negative outcomes, and reported on their positive beliefs about worrying. Children associated worrying more strongly with fear than with thinking. However, this relationship was moderated by age. Older children reported that worry was more closely related to thinking and less closely related to fear. Furthermore, children who reported more thinking, rather than fear, about negative outcomes were also more likely to report that worrying had beneficial effects. Results suggest important changes in the nature of worrying during late childhood.

Keywords

child worry fear problem-solving coping

Worrying is a common experience in everyday life. Most adults report worrying at least once a week (Tallis, Davey, & Capuzzo, 1994; Szabó & Lovibond, 2002, 2006), and children as young as 4 to 6 years of age are able to report on their worries (Muris, Merckelbach, Gadet, & Moulaert, 2000). Excessive worrying, however, is a clinically significant phenomenon. It is associated with several anxiety disorders, and is the cardinal feature of Generalized Anxiety Disorder in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; American Psychiatric Association, 2013), both in adults and children. Although there is now a large body of empirical and theoretical work available concerning normal and pathological worry in adults, surprisingly little is known about the characteristics, function, and developmental course of worry in youth (Cartwright-Hatton, 2006).

Current research interest in worry was initiated by Borkovec, Robinson, Pruzinsky, and DePree (1983), who first defined this phenomenon as

. . . a chain of thoughts and images, negatively affect-laden and relatively uncontrollable. The worry process represents an attempt to engage in mental problem-solving on an issue whose outcome is uncertain but contains the possibility of one or more negative outcomes. Consequently, worry relates closely to fear process. (p. 10)

Subsequent research in adults has shown that worrying is a predominantly verbal thought process, with relatively less imagery present (Borkovec & Inz, 1990; Huang, Szabó, & Han, 2009). Worrying is associated with symptoms of vigilance and tension, rather than the hallmark physiological arousal symptoms of anxiety or fear (Freeston, Dugas, Letarte, & Rheaume, 1996; Szabó, 2011). It has been proposed, therefore (e.g., Sibrava & Borkovec, 2006), that one of the functions of worrying is to suppress mental imagery about possible future outcomes and to reduce the aversive physiological arousal symptoms associated with such imagery. In addition to this subtle cognitive avoidance function, however, the primary avoidance function of worry is to enable individuals to mentally search for ways to avoid perceived future danger, or to prepare to cope with it, should it occur (Mathews, 1990; Sibrava & Borkovec, 2006). Indeed, although different theoretical approaches emphasize alternative characteristics of worry (e.g., Davey, 1994; Dugas, Gagnon, Ladouceur, & Freeston, 1998; Hirsch & Mathews, 2012; Wells, 1999), they all tend to agree that normal worrying involves problem-solving or coping attempts. The success of such attempts may be thwarted by pathological worriers’ intolerance of uncertainty (Dugas et al., 1998), lack of problem-solving confidence (Davey, 1994), or ineffective thought control strategies (Wells, 1999).

There is much less known about the defining characteristics of worry in youth. The few available developmental analyses to date (Kertz & Woodruff-Borden, 2011; Vasey, 1993; Vasey & Daleiden, 1994) propose that children are able to worry in an adult-like fashion from about 7 to 8 years of age. It has been argued that from about this age, children are able to foresee chains of increasingly negative future outcomes and their consequences, as well as being able to switch from mental imagery to verbal thought while rehearsing such outcomes. Before the development of these abilities, young children’s worries are thought to be closely related to fear, involving negative mental imagery and physiological arousal (Vasey, 1993; Vasey & Daleiden, 1994). Interestingly, however, Vasey’s analysis did not attempt to account for developments in the problem-solving or coping function of normal worrying observed in adults. Instead, worry was conceptualized merely “as a process characterized by the anticipation and elaboration of catastrophic possibilities” (Vasey & Daleiden, 1994, p. 192); any beneficial effects were explicitly ruled out from this definition.

Consistent with this approach, research studies exploring the nature and determinants of worrying in children have often defined worry to the young participants as “thinking about a bad thing that may happen” (Muris et al., 2000, p. 52), or involving “things that people think really hard about, or think about a lot” (Henker, Whalen, & O’Neil, 1995, p. 689). Similarly, child clinical assessment tools define worry to children as “when you keep thinking about things over and over” (Silverman & Albano, 1996, p. 39). In some studies, worrying has been differentiated from fear by pointing out to participants that fear involves physiological arousal and occurs in the immediate presence of danger, while worry is more anticipatory in nature and involves more thinking (Muris et al., 2000). These studies have documented important aspects of worrying in youth. However, the strategy of providing pre-determined, adult definitions of “worry” to child participants does not allow us to better understand what children mean when they report on their worries in the absence of adult definitions.

To improve the developmental sensitivity of our assessment, understanding and treatment of children’s anxiety-related experiences (Schniering, Hudson, & Rapee, 2000), children’s own definitions of these phenomena also need to be taken into account. To that end, a clear documentation of possible age-related changes in children’s experience of the concept they call “worry” is necessary. As a first step, research evidence is needed to show whether school-aged children’s reports of “worrying” in fact represent a thinking process that is different from fear. Furthermore, it needs to be established whether this thinking process merely involves an elaboration of increasingly catastrophic possibilities (Vasey & Daleiden, 1994), or, alternatively, whether it is also associated with perceived beneficial effects of worrying. Establishing such parameters of worrying in non-anxious youth would then allow us to better delineate the pathological aspects of clinically significant worrying at various ages (Cicchetti, 2006).

Children have difficulty in explicitly defining “worry” or verbalizing subtle differences between “worry” and other anxiety-related phenomena (Henker et al., 1995). Therefore, a small number of studies have attempted to explore this question using indirect strategies (Campbell, Rapee, & Spence, 2000; Szabó, 2007, 2009). In these studies, participants of different ages were asked to rate how much they “worry about,” are “afraid of,” and “think about” the same list of negative outcomes. In the absence of pre-determined definitions of fear and worry provided to them, primary-school-aged children did not differentiate between outcomes they “felt afraid of” or “worried about,” whereas adults clearly distinguished between such outcomes (Szabó, 2007). Furthermore, compared to adults, children were less likely to associate worrying with “thinking” (Campbell et al., 2000; Szabó, 2007). In other words, it appears that compared to adults, 7- to 12-year-old children experience worrying as more similar to fear and involving less “thinking.”

Unfortunately, none of these studies examined whether there were any age-related differences in the phenomenology of worry within the 7- to 12-year-old range. In addition, although some children express positive beliefs about the problem-solving or coping functions of worry (e.g., Bacow, Pincus, Ehrenreich, & Brody, 2009; Muris, Meesters, Merckelbach, Sermon, & Zwakhalen, 1998; Wilson & Hughes, 2011), it is not yet known whether the “thinking” aspect of their worries is associated with the early stages of the emergence of its problem-solving function, or, alternatively, whether worrisome thinking merely involves a rehearsal of increasingly negative anticipated outcomes, as suggested by Vasey (1993). There is now substantial evidence showing that during middle and late childhood, children’s cognitive coping strategies become increasingly sophisticated, and complex methods of mental problem-solving emerge (Zimmer-Gembeck & Skinner, 2011). Considering this development, it is possible that the nature of worrying also changes during this period.

The present study, therefore, was conducted to further explore the nature of worrying in 7- to 12-year-old children. We hypothesized that within this age group, older children would experience worrying as increasingly involving a thinking process, and having a decreasing association with fear. Furthermore, the extent to which participants report “thinking” about negative outcomes would be positively associated with a perception that worrying has beneficial effects.

Method

Participants

The sample included 93 primary schoolchildren attending Grades 2 to 6 (M_age = 10.00 years; SD = 1.19; minimum = 7.85; maximum = 12.30; 48.39% girls). There were 8 students recruited from Grade 2, 21 from Grade 3, 32 from Grade 4, 18 from Grade 5, and 14 from Grade 6. There were no differences in the gender distribution of participants according to school grade (η = .007), and no significant age differences between boys and girls (M_age for boys = 10.07, M_age for girls = 9.91, t = −.65, p = .34). Participants were recruited from one independent school, two out-of-school-hours-care centers associated with government schools, and a holiday camp including children from both independent and government schools. Response rates varied between 25% and 50%, which is consistent with rates from prior similar studies (Szabó, 2007, 2009). Participants’ suburb of residence was used as a proxy index of their socio-economic status (SES) based on local income level, employment, and education. Most participants were found residing in suburbs classified as high SES, with 82% classified in the two highest deciles (Australian Bureau of Statistics, 2006). The majority (88%) of the 92 children who were able to give this information reported that they were born in Australia. Furthermore, 61% reported that their mother was born in Australia, and 59% reported that their father was born in Australia. Other backgrounds included Europe (17% of mothers and 19% of fathers), Asia (9% of mothers and 3% of fathers), and New Zealand, Polynesia, and Melanesia (5% of mothers and 9% of fathers).

Materials

The Child and Adolescent Worry Scale (CAWS)—Revised versions

In its original format, the CAWS (Campbell & Rapee, 1994; Szabó, 2007) is a 20-item self-report questionnaire assessing the degree to which children aged 6 to 16 years worry about a variety of outcomes happening to them (e.g., “being lonely” or “breaking an arm or a leg”). Children are asked to rate how much they worry about the outcomes happening to them on a 3-point scale from 0 = “don’t really worry” to 2 = “worry a lot.” The CAWS has been found to have good convergent and discriminant validity across age, gender, and in both clinical and non-clinical populations (Campbell & Rapee, 1994). This scale was adapted by Szabó (2007) to include versions where children are able to give ratings about how much they fear and think about negative outcomes. Each of these versions includes the same items, but the instructions and response options are different. For CAWS-Fear, participants are asked to rate how afraid they are of the outcomes happening to them from 0 = “not really afraid” to 2 = “very afraid.” For CAWS-Think, participants are asked to rate how much they think about each of the outcomes happening to them from 0 = “not really think about it” to 2 = “think about it a lot.” A second modification was made for the purpose of this study. The number of items on all three versions was reduced from the original 20 to 17 items, because of concern that reporting on the more distressing items (e.g., “dying”) three times could be upsetting for the young participants. All three versions of the CAWS had excellent internal consistencies in the present study, with Cronbach’s alphas from .94 to .95.

The Metacognitions Questionnaire for Children—Positive Beliefs Subscale (MCQ-C[PB])

The MCQ-C (Bacow et al., 2009) is a self-report measure of the metacognitive processes associated with worry in children, developed from the adult version of the Metacognitions Questionnaire-30 (Wells & Cartwright-Hatton, 2002). The MCQ-C has been found to have good concurrent, convergent, and discriminant validity in youth aged 7 to 16 years (Bacow et al., 2009). In the present study, we used the “Positive Beliefs about Worry” (PB) subscale of the MCQ-C to assess the extent to which children perceive worry as having a beneficial function. The scale consists of six items. Most of these refer specifically to problem-solving or cognitive coping (e.g., “Worrying helps me solve problems” or “When I am confused, worrying helps me sort things out”), and one reflects a more generalized positive effect (“Worrying helps me feel better”). Children indicate how much they “generally agree” with the statements on a 4-point scale ranging from 1 = “do not agree” to 4 = “agree very much.” In the present sample, the MCQ-C(PB) was found to have satisfactory internal consistency, with a Cronbach’s alpha of .69. This value is similar to that previously reported in a non-clinical sample by Bacow et al. (2009).

Procedure

The study received ethical approval from all relevant institutional ethics committees. Only children who returned consent forms signed by both themselves and their parents by the date of data collection took part in the study. Questionnaires were completed in groups of up to 30 children at school, or on out-of-school-care or holiday camp premises. To prevent order effects, the order of item presentation was different between the three versions of the CAWS, and the order of the three versions of the CAWS was counterbalanced. The MCQ-C(PB) was always completed last, to minimize any potential biasing effect of items that describe the benefits of worrying. Because we were interested in understanding the children’s subjective experience of worry, no pre-determined definitions were given to the participants.

Results

Descriptive statistics and Pearson correlation coefficients for all variables are presented in Table 1. The three versions of the CAWS measuring Worry, Fear, and Thinking were positively associated with each other and with the MCQ-C(PB). Age had near-zero bivariate relationships with these variables. A series of t tests found no significant differences between boys and girls on any of the study variables, largest t(91) = 1.27, p = .21, for CAWS-Worry.

Table 1.

Mean Scores (SD), Pearson’s Correlations Among CAWS-Worry, CAWS-Fear, CAWS-Think, and MCQ-C(PB) Scores, and Age.

	1	2	3	4	5	$\bar{X}$ (SD)
CAWS-Worry	—					11.03 (9.38)
CAWS-Fear	.84***	—				12.28 (9.87)
CAWS-Think	.82***	.68***	—			10.28 (8.83)
MCQ-C(PB)	.35***	.35***	.42***	—		8.53 (2.80)
Age	−.04	−.09	−.01	.02	—	10.00 (1.19)

Note. CAWS-Worry = Child and Adolescent Worry Scale, Worry version; CAWS-Fear = Child and Adolescent Worry Scale, Fear version; CAWS-Think = Child and Adolescent Worry Scale, Think version; CAWS = Child and Adolescent Worry Scale (Campbell & Rapee, 1994); MCQ-C(PB) = Positive Beliefs about Worry subscale of the Metacognitions Questionnaire for Children (Bacow, Pincus, Ehrenreich, & Brody, 2009).

***

p < .001.

To test our first predictions, a moderated hierarchical multiple regression analysis was carried out, with CAWS-Worry as the criterion variable. Age, CAWS-Fear and CAWS-Think were entered as predictors in the first step. The interaction term between Age and CAWS-Fear and the interaction term between Age and CAWS-Think were entered in the second step. Age was calculated and entered as a continuous variable, representing the time period between the date of data collection and each participant’s date of birth in years and months. Scores on each of the three CAWS scales were mildly positively skewed (e.g., CAWS-Worry skewness = .580; Kolmogorov-Smirnov statistic = .115, df = 93, p < .005). Square-root transformations reduced skew, but using transformed variables did not change the pattern of results. Therefore, analyses using untransformed variables are reported for reasons of clarity. Variables were mean-centered to reduce the possibility of multicollinearity effects. According to commonly accepted thresholds, a Variance Inflation Factor (VIF) larger than 5.00 or 10.00 and Tolerance values smaller than .10 or .20 indicate a collinearity problem (Keith, 2006). In this analysis, the largest VIF was 2.29 and the smallest Tolerance was .44. These were associated with the interaction term between Age and CAWS-Fear. Therefore, VIF was below 5.00 and Tolerance was above .20 for all predictor variables, meeting the more stringent criteria to indicate that multicollinearity was unlikely to affect the results.

Results of this analysis are presented in Table 2. Step 1 of the analysis shows that across the whole 7- to 12-year-old age group, CAWS-Fear explained more variance in CAWS-Worry, compared to CAWS-Think. However, both interaction terms at Step 2 were also significant, qualifying these findings. Specifically, b values associated with the significant interaction terms indicated that as Age increased by one unit, the slope of the regression of CAWS-Worry on CAWS-Fear decreased by .18 units. Conversely, as Age increased by one unit, the slope of the regression of CAWS-Worry on CAWS-Think increased by .17 units. These significant interactions are graphically illustrated in Figure 1, which shows that the linear relationship between Worry and Fear was relatively stronger in younger children, whereas the linear relationship between Worry and Think was relatively stronger in older children.

Table 2.

Hierarchical Multiple Regression Analysis Testing the Moderating Role of Age in Explaining Variance in Worry Ratings.

	Criterion variable: Worry ratings (n = 92)
Predictor variables	R ²	ΔR²	B	β	t
Step 1	.83***
Age			.06	.01	0.19
Fear ratings			.51	.53***	8.82
Think ratings			.49	.46***	7.61
Step 2	.85***	.02**
Age			−.11	−.02	−0.34
Fear ratings			.48	.51***	8.89
Think ratings			.52	.49***	8.47
Age X Fear ratings			−.18	−.22***	−3.55
Age X Think ratings			.17	.20**	3.24

Note. Worry ratings = CAWS, Worry version; Fearing ratings = CAWS, Fear version; Think Ratings = CAWS, Think version; CAWS = Child and Adolescent Worry Scale (Campbell & Rapee, 1994).

p < .005. ***p < .001.

Figure 1.

Simple slopes illustrating the relationship of Worry to Fear and Thinking in younger (7- to 9-year-old, n = 50) and older (10- to 12-year-old, n = 43) children.

The second aim of this study was to explore the relationship between children’s ratings of how much they think about negative outcomes and their perceptions that worry serves a beneficial function. Children’s perceptions of the benefits of worrying were measured by the MCQ-C(PB). As shown in Table 1, scores on the MCQ-C(PB) were significantly and positively correlated with all three versions of the CAWS, which were strongly correlated with each other. To test our hypothesis that the extent to which participants report “thinking” about negative outcomes is uniquely associated with their perception that worrying has positive effects, a simultaneous multiple regression analysis was conducted. MCQ-C(PB) was entered as the criterion variable, and both CAWS-Fear and CAWS-Think were entered as predictors to control for the overlap between these two measures. Diagnostic indices for multicollinearity were well within commonly accepted thresholds (VIF = 1.84, Tolerance = .54 for both predictors). The model explained a significant amount of variance in MCQ-C(PB) scores (adjusted R² = .17, F = 10.11, p < .001). However, only CAWS-Think retained a significant association with MCQ-C(PB) (CAWS-Think, b = .11, β = .33, t = 2.54, p < .05, squared semi-partial correlation = .059) when CAWS-Fear was also in the equation (CAWS-Fear, b = .04, β = .13, t = 1.00, p > .05, squared semi-partial correlation = .009).

Discussion

The present study aimed to expand upon previous findings concerning the phenomenology of children’s worrying (e.g., Campbell et al., 2000; Szabó, 2007) by examining possible age-related differences in the experience of worrying during late childhood. We hypothesized that older children would experience worrying as increasingly involving a thinking process, and having a decreasing association with fear. Furthermore, we predicted that the extent to which participants report “thinking” about negative outcomes would be positively associated with their reports that worrying has beneficial effects. Results supported both of these hypotheses.

Consistent with previous findings (Szabó, 2007), our results have shown that children aged 7 to 12 years associate their experience of worrying more strongly with fear than with thinking about negative outcomes. In researching both normal and clinically significant worry in children, it is common practice to define “worrying” to child participants as a thinking process, and to differentiate it from fear (Henker et al., 1995; Muris et al., 2000; Silverman & Albano, 1996). While this practice allows researchers and clinicians to assess the extent to which children engage in an adult-like worry process, it does not allow us to assess worry as understood and implicitly defined by the children themselves. The present results, together with those of previous studies (Campbell et al., 2000; Szabó, 2007, 2009), indicate that school-aged children’s reports on “worry” may in fact reflect a concept that is qualitatively different from adult worry.

Furthermore, the significant interactions with age in the present study indicate that as children mature, their worries increasingly acquire the “thinking” process characteristic of adult worry, and become more differentiated from their concept of “fear.” While the size of the interaction effect was relatively small, these findings are especially noteworthy considering the restricted age range of the sample, and the relatively few children in the youngest age group in this study. The current study contributes to accumulating evidence suggesting that there are important changes in the nature of worry during late childhood, and questioning previous proposals that an adult-like worry process appears at about 7 to 8 years of age (Vasey, 1993). The precise age at which an adult-like worry process emerges is still unknown, and research is now needed to clarify this question. The findings further highlight the need for researchers to be mindful of potential developmental differences in the phenomena they examine, and to exercise caution in applying adult definitions and theories of these phenomena to youth (Cartwright-Hatton, 2006).

The hypothesis concerning the association between “thinking” about negative outcomes and the perceived positive functions of worry was also supported by the results. Thinking about negative outcomes was associated with perceived beneficial effects of worrying, when level of fear was held constant. In other words, among children who reported experiencing the same level of fear, those who reported “thinking” more about negative outcomes were also more likely to believe that worrying had beneficial effects. These children reported that worrying helps to “solve problems,” to “sort things out” and to “be organized,” and that it can lead to having “less problems in the future.” These findings show that while children’s worrisome thinking may partly reflect a “catastrophizing” process (Vasey, 1993), it can also include attempts to cope with or problem-solve about negative outcomes (Sibrava & Borkovec, 2006; Szabó & Lovibond, 2004). The data further underline the need for a new developmental theory of worrying that takes the emerging problem-solving aspects of normal worry into account, in addition to its “catastrophizing” content. The emergence of such problem-solving aspects may be associated with the development of increasingly complex cognitive coping abilities between middle childhood and early adolescence (Zimmer-Gembeck & Skinner, 2011).

It is important to note, however, that in this study we assessed children’s perception of the beneficial effects of worry, rather than actual problem-solving during worrying or the success of problem-solving attempts. Studies documenting the content of children’s worry episodes have shown that, while children do make problem-solving attempts, few of their worry episodes involve successful problem-solving (Muris et al., 1998; Szabó & Lovibond, 2004). Perceptions of coping or problem-solving in the present study, therefore, may partly indicate superstitious beliefs, or the negative reinforcement of the worry process via the association of worrying with the non-occurrence of the anticipated event that probably would not have occurred. Hence, an important avenue for future research would be to explore the degree to which children’s perceptions of the beneficial effects of worry in fact reflect successful problem-solving. To investigate this question, studies using detailed thought-listing procedures to document the content of children’s worry episodes (e.g., Szabó & Lovibond, 2004) are needed.

The findings of this study contribute to a more developmentally appropriate conceptualization of worry in non-anxious children and can provide the background against which further studies may explore similar questions in clinically anxious youth. Before making any recommendations for clinical assessment or treatment, it is important to compare the present results with similar outcomes in clinically anxious children. For example, it is not presently known whether 7- to 12-year-old anxious children also increasingly experience worrying as a “thinking” process as they mature, whether they also perceive that thinking about negative events is associated with beneficial effects of worrying, and whether there are any differences between non-anxious and clinic-referred anxious children in such fundamental aspects of worrying. The few available studies that address this question suggest that clinic-referred anxious children report relatively fewer and less successful problem-solving attempts during worry, compared to others (Muris et al., 1998; Szabó & Lovibond, 2004).

The current findings need to be interpreted in light of the study’s methodological limitations. All data were collected via self-report questionnaires, which are open to biases introduced by memory effects, reading ability, and social desirability. The use of self-report in this study was necessary, as we were interested in the subjective phenomenology of worrying as experienced by the children. Nevertheless, the correlations may have been inflated by method effects, and future research using alternative data collection methods is now needed. Such research, if completed in samples including children with a broader range of SES backgrounds, would also aid in establishing the generalizability of the findings. Furthermore, based on the design of this study, it is not possible to ascertain if the results reflect changes in children’s experiences of worrying, or alternatively, whether they reflect age-related differences in participants’ definitions of “worry” in comparison with “fear.” To investigate these questions, studies using detailed thought-listing procedures to document the content of children’s worry episodes are needed.

Finally, although we aimed to uncover age-related changes in worrying, the cross-sectional design of the study does not allow us to draw definitive conclusions about these changes. Age-related differences in cross-sectional studies may reflect either a developmental progression or merely cohort effects. However, it is difficult to explain our findings by evoking any potential explanations other than the effects of cognitive maturation, for example, the development of cognitive coping skills, with increasing age (Zimmer-Gembeck & Skinner, 2011). Longitudinal studies are now needed to provide a clearer developmental perspective. Such further investigations may be able to more precisely delineate the age at which worrying is first experienced as a verbal-linguistic thought process associated with coping attempts, as previously observed in adults (Davey, Tallis, & Capuzzo, 1996; Freeston, Rheaume, Letarte, Dugas, & Ladouceur, 1994; Mathews, 1990; Szabó & Lovibond, 2002, 2006; Tallis et al., 1994; Wells & Cartwright-Hatton, 2002).

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was partly supported by an Australian Government National Health and Medical Research Council grant (NHMRC, Project Grant 1010738) awarded to the second author.

Author Biographies

Imogen Carr graduated from the University of Sydney with Bachelor of Science (Hons.) in 2011, majoring in psychology. She has been working as a research assistant in developmental and clinical psychology since graduating.

Marianna Szabó is a senior lecturer in psychology at the University of Sydney, and a clinical psychologist in private practice. Her PhD research, completed in 2002, compared the characteristics of worrying between adults and children. She retained an interest in this research area, while expanding it to include the investigation of other emotional experiences, such as depression or stress, in children, adolescents, and adults.

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