Introduction
Adolescence is a period of personality development and is associated with internal turmoil, spanning between the ages 10-19 [1]. This period includes transformations in the body, mind, visualization, and imagination [2]. Puberty occurs in this period [3]. The physical changes caused by puberty are often considered as a crisis for adolescents, and can lead to the creation and continuation of many problems. Adolescent girls face more health, psychological, and social problems than boys due to physiological differences, social roles, and prevailing social norms [4]. Adolescence is a vulnerable period for mental health, which can lead to many psychological disorders, such as anxiety [5]. Anxiety is a painful feeling determined by the current traumatic situation or the expectation of undefined threats, often accompanied by physical symptoms [6]. Research indicates that anxiety is more prevalent in girls than in boys [7]. A meta-analysis study has estimated a global anxiety prevalence of 13.4% in adolescents [8]. Anxiety is a multifaceted phenomenon and has different aspects, including physical, cognitive, emotional, and interpersonal [9]. Psychologists such ::as char::les Z. Spielberger and Richard L. Gorsuch categorize anxiety into state and trait types [10]. State anxiety is defined as a temporary emotional state in response to a perceived threat [11], whereas trait anxiety refers to a more general tendency to respond to perceived environmental stressors, which is relatively stable [12]. 
Given that anxiety is often related to negative thoughts and appraisal of situations, cognitive therapy can be an effective approach to mitigate it, whose clinical efficacy has been shown by various studies [3]. Through cognitive therapy, individuals learn how their thoughts contribute to the onset and persistence of anxiety symptoms and how to mitigate these thought patterns to reduce the occurrence and severity of their reactions. Michael Frey’s cognitive therapy approach not only modify a person’s rational beliefs but also addresses their emotional beliefs and teach individuals to move from abnormal information processing methods to normal methods. By creating a change and transformation in the individual’s cognitive system, it enables their reactions to be changed by cognitive characteristics, allowing the person to correctly understand and interpretate the facts [8]. This method is a non-pharmacological treatment. Its advantage compared to other psychotherapy methods is that it directly deals with thoughts and feelings, which are important in all mental disorders. Additionally, its implementation in a group format can increase its effectiveness. Therefore, since the individual benefits from the support of group members which can expand his/her social skills, and given that the approach is cost- and time-effective, group therapy is more efficient than individual therapy [13]. 
Research suggests that anxiety in adolescence can disrupt interpersonal relationships. Since social functioning is crucial during adolescence, anxiety can negatively affect social interactions, for example, by reducing the acceptance of peers and low friendship quality [14]. Anxious adolescents tend to be less engaged in school activities, directly affecting their academic performance and grades [15]. They also experience more psychological issues than their peers, which disrupts their normal life and daily performance [16]. Therefore, early intervention during this critical period is essential to prevent psychological disorders in adulthood [1]. Physically and psychologically healthy children and adolescents are imperative for social development [17]. Investigating solutions to manage the anxiety of adolescents is crucial not only for the individuals and their family but also for the schools and even the government. Therefore, this study aims to examine the effect of cognitive group therapy on state and trait anxiety of female adolescents.

Materials and Methods
This is an open-label randomized controlled clinical trial with a pre-test/post-test/follow-up design. The study population consists of the students from Ayatollah Hashemi Rafsanjani High School for girls in Sari, Iran, in December 2022. Out of 110 students, the parents of 76 students allowed them to participate in the study. After providing explanations about the study objectives, 54 students expressed their willingness to participate in the study. Then, they completed Spielberger’s state-trait anxiety inventory (STAI). Those who achieved a minimum score of 30 were included. In this regard, 30 students were purposefully selected and randomly (lottery method) divided into two groups of 15 including intervention and control groups (Figure 1). The sample size of 15 per group was determined using a formula (comparing two means) and based on previous study [18]. Inclusion criteria were age 13-16 years (first-grade high school students), no incurable physical diseases such as cancer or multiple sclerosis, written consent from both parents and students to participate in the study, no major psychiatric disorders such as schizophrenia, no simultaneous attending in other psychological interventions or drug therapies, and a minimum STAI score of 30. The exclusion criterion was the absence from more than two treatment sessions. It should be noted that three students had lower scores in the post-test and follow-up phases than in the pre-test phase; however, since their scores was >50, they were selected and referred to the psychiatric center at the discretion of the school counselor and the parents.
The intervention group received cognitive group therapy at 12 weekly sessions of 90 minutes according to Michael Frey’s proposed protocol [19] presented in Table 1, which was provided by an expert (MS in clinical psychology), supervised by an expert (PhD in general psychology).


The control group did not receive any treatment during the study but was put on a waiting list to receive the cognitive therapy after the end of the study. 
Assessments were carried out in three phases: Pre-test, post-test (March 2023), and follow-up 45 days after the intervention (April 2023), by the first author using the STAI. This tool was developed in 1970 by Charles Z. Spielberger, and has 40 items; items 1-20 measure the state anxiety and items 21-40 assess the trait anxiety. A score of 20-29 shows mild anxiety; score 30-49= mild anxiety, score 50-69= moderate anxiety, and score 70-80= severe anxiety. The Cronbach’s α coefficient is 0.92 for the state anxiety subscale and 0.90 for the trait anxiety subscale, with a test-retest coefficient of 0.62 for the state anxiety and 0.68 for the trait anxiety subscale [20]. This questionnaire has been standardized in Iran, which reported reliability scores of 0.92 and 0.91 for state and trait anxiety, respectively. Its validity has been confirmed at a high level [21]. 
Data were analyzed in SPSS software, version 22, and the significance level was set at 0.05. The repeated measures analysis of variance (ANOVA) with was used to assess the effects of treatment and time.

Results 
Table 2 presents the demographic characteristics of the two groups and Table 3 provides the mean scores for the study variables at three phases for each group.




Levene’s test results confirmed that the assumption of equal variances for the state anxiety (F=3.132, P=0.088) and trait anxiety (F=4.164, P=0.051). Table 4 presents the results of repeated measures ANOVA, using the Greenhouse-Geisser correction, for the effect of cognitive group therapy on the STAI score in female adolescents.


The treatment significantly reduced state anxiety and trait anxiety in the intervention group compared to the control group (P<0.05). Moreover, both main effect and interaction effect of time and group were significant on state anxiety and trait anxiety. The Bonferroni post hoc test was used for the pairwise comparison in the intervention group. The results are shown in Table 5.


As can be seen, the scores of state anxiety and trait anxiety were significantly different between the three assessment phases in the intervention group.

Discussion
The findings of this research demonstrate that cognitive group therapy had a significant effect on state and trait anxiety of anxious adolescent girls. We found no similar study to compare the results. A study in Kish Island, Iran, revealed that cognitive-behavioral group therapy reduced state-trait anxiety in girls aged 15-17 and enhanced their mental health [22]. This is consistent with our results, although we used cognitive therapy alone, without behavioral treatment. A study explored the effectiveness of cognitive group therapy based on Michael Frey’s method on reducing rumination and depression of female high school students, where the findings confirmed the effectiveness of cognitive group therapy [8]. A study on the effect of metacognitive group therapy for adolescents with anxiety disorders and depression also indicated its promising results [23]. In another study, the effects of cognitive-behavioral group therapy on rumination and anxiety among patients with multiple sclerosis were examined. The findings indicated that cognitive-behavioral group therapy led to significant improvements because in this type of thinking and feeling treatment, patients to organized their absolute beliefs about themselves and others, and the therapy effectively reduced negative imagery and dysfunctional attitudes related to irrational thoughts [24]. Additionally, a related study demonstrated the efficacy of cognitive-behavioral therapy in alleviating anxiety during the pandemic, which caused a state anxiety created by an unstable condition [25]. According to studies, to manage psychosocial factors, it is necessary to use psychological methods (such as cognitive group therapy) for the anxious adolescents [26]. 
In explaining the effectiveness of cognitive group therapy on the state and trait anxiety, it can be said that this intervention which is based on cognitive processes and emotional reactions, affect the persistence of psychological problems in the individuals since people’s feelings and behaviors are influenced by their perception of events. What is important in explaining psychological problems is the way people interpret and perceive a distressing event and the cognitive content of their reactions to achieve the flow of thoughts and schemas that affects a person’s perceptual structure and behavior control assessment. This therapy is a direct and structured approach to help individuals identify and eliminate distorted and ineffective thinking patterns through regular and organized homework. In addition, since it was performed in a group format and the group members benefit from each other’s skills, it had a great impact. By challenging negative thoughts, it improve the planning to achieve goals and reduces anxiety [5, 10, 11]. 

Conclusion
One of the disadvantages of this clinical trial was the use of only one experimental group. In addition, the results cannot be generalized to all anxious people, since the intervention was conducted only on female samples. For future research, it is recommended to include both male and female adolescents and to use a longer study duration to observe long-term effects. The providers of educational, therapeutic, and support services to adolescents in Iran are recommended to use cognitive group therapy, along with other methods for the psychological treatment of anxious adolescents.

Ethical Considerations
Compliance with ethical guidelines
This study has ethical approval from the ethics committee of Islamic Azad University, Sari branch (Code: IR.IAU.SARI.REC.1401.232).

Funding
The article was extracted from the master's thesis of Fatemehzahra Khayati Ghasemkheyli, approved by Department of Psychology, Faculty of Medicine, Sari Branch, Islamic Azad University.

Authors' contributions
The authors contributed equally to preparing this article.

Conflict of interest
The authors declared no conflict of interest.

References

1. Kasir S, Hosseini Mehr M, Agili Rad S, Sherhani M A. [Investigating the effectiveness of group cognitive therapy on students’ emotional reactions (Persian)]. Soc Educ. 2017; 9:111-9. [Link]
2. Hassanloo F, Zahraei, S, Tavoli, A. [A phenomenological investigation of the lived experience of adolescence among adolescents based on the mentalization capacity (Persian)]. J Appl Psychol Res. 2023; 14(3): 63-82. [DOI:10.22059/JAPR.2023.348221.644373]
3. Rafsanjani Akbaribadi Z, Hosseinzadeh Taqvai M, Danesh I, Kraskian Mojmanari A, Tarimoradi A. [Comparison of the effectiveness of compassionate mind group training and mindfulness-based cognitive therapy group training on self-balance and anger control in female adolescents (Persian)]. Rooyesh-e-Ravanshenasi. 2022; 11(1): 81-9. [Link]
4. Soheili salek Z, Farrokhi N, Poushaneh K. [Effectiveness of Positive Youth Development Education to Parents on psychological capital and anxiety of female adolescents (Persian)]. Islam Iran Fam Stud J. 2023; 2(4): 19-31. [Link]
5. Marlow M, Skeen S, Grieve CM, Carvajal-Velez L, Åhs JW, Kohrt BA,et al. Detecting depression and anxiety among adolescents in south Africa: Validity of the isiXhosa patient health questionnaire-9 and generalized anxiety disorder-7. J Adolesc Health. 2023; 72(1S):S52-60. [DOI:10.1016/j.jadohealth.2022.09.013] [PMID]
6. Saedi F, Khanjani Z. [A comparative study of three attachment styles (secure, ambivalent, avoidant) in adolescents with internalizing symptoms of depression and anxiety (Persian)]. Women Fam Stud. 2016; 10( 38):153-37. [Link]
7. Behzadpur S, Pouretamad H, Akbari Zardkhaneh S. [Risk factors of anxiety in children and adolescents with autism spectrum disorder: A systematic review (Persian)]. J Child Ment Health. 2021; 7(4):165-80. [Link]
8. Rostami M. [Effectiveness of group cognitive therapy by Michael Free method on reducing rumination and depression in female high school students (Persian)]. J Educ Psychol Stud. 2021; 18(41):150-71. [DOI:10.22111/JEPS.2021.6194]
9. Nasiri Z, Ahadi H, Kalhornia Golkar M, Teymouri S, Khadem Ghaebi N. [Effect of mindfulness-based cognitive therapy on intolerance of uncertainty in infertile women undergoing in vitro fertilization treatment (Persian)]. J Health Res Commun 2022; 7(4):75-80. [Link]
10. Zeinali S. [The association between anxiety and mindfulness while emphasizing the mediating role of attention control functions (Persian)]. Shenakht J Psychol Psychiatry. 2022; 9(3):111-22 . [DOI:10.32598/shenakht.9.3.111]
11. Peng L, Hu X, Lan L, Xu C, Li M. The moderating role of resilience in the relationship between state and trait anxiety and post-traumatic growth of medical freshmen. Acta Psychol (Amst). 2022; 230:103741. [DOI:10.1016/j.actpsy.2022.103741] [PMID]
12. Roohzadeh Z, Lotfi H, Mirzaian B. [The effect of state-trait anxiety on the choise of cognitive clarity situation (Persian)]. Cogn Strategies Learn. 2021; 9(16):223-43. [DOI:10.22084/J.PSYCHOGY.2020.21718.2159]
13. Gahamari M, Elhifar H. [The effectiveness of cognitive group therapy in decreasing general anxiety and test anxiety of students (Persian)]. J Behav Sci. 2012; 3(10).57-67. [Link]
14. Yang X, Zhou Z, Liu Q, Fan C. Mobile phone addiction and adolescents’ anxiety and depression: The moderating role of mindfulness. J Child Fam Stud. 2019; 28(3):822-30. [DOI:10.1007/s10826-018-01323-2]
15. Lynch H, McDonagh C, Hennessy E. Social anxiety and depression stigma among adolescents. J Affect Disord. 2021; 281:744-50. [DOI:10.1016/j.jad.2020.11.073] [PMID]

16. Williams AL, Craske MG, Mineka S, Zinbarg RE. Neuroticism and the longitudinal trajectories of anxiety and depressive symptoms in older adolescents. J Abnorm Psychol. 2021; 130(2):126-40. [DOI:10.1037/abn0000638] [PMID]
17. Kamali S, Abolmaali Alhoseini Kh. [Predicting cognitive emotion regulation strategies according to family communication processes and perfectionism in high school adolescent girls (Persian)]. Appl Psychol. 2017; 10(4): 291-310. [Link]
18. Gall D, Borg W, Gal J. Quantitative and qualitative research methods in educational sciences and psychology [A. Nasr, Persian trans.]. Tehran: Samt Publications; 2012. [Link]
19. Frey M. ‎Cognitive therapy in groups: Guide lines and resources for practice [A.Sahibi, H. Hamidpour, & Z. Indoz, Persian trans]. Tehran: Sayeh Sokhn; 2016. [Link]
20. Spielberger CD, Gorsuch RL, Lushene R,Vagg PR, Jacobs GA. Manual for the state- trait anxiety inventory. Palo Alto, CA: Consulting Psychologists Press; 1983. [Link]
21. Safavi M, Marofi S. [Correlation between attachment styles and state- or trait- anxiety (Persia)]. Med Sci. 2013; 22(4):307-12. [Link]
22. Mirza Hosseini H, Kabiri Qomi N. [The effectiveness of group cognitive therapy based on Michael Frey on the cognitive regulation of emotion and reducing anxiety in depressed girls (Persian)]. J Anal Cogn Psychol. 2018; 10(38):37- 48. [Link]
23. Thorslund J, McEvoy PM, Anderson RA. Group metacognitive therapy for adolescents with anxiety and depressive disorders: A pilot study. J Clin Psychol. 2020; 76(4):625-45.  [DOI:10.1002/jclp.22914] [PMID]
24. Shahnazari M, Hanari H. [The effect of cognitive-behavioral therapy group on rumination and anxiety in patients with multiple sclerosis (Persia)]. J Appl Psychol Res. 2015; 7(1):155-67. [Link]
25. Egan SJ, McEvoy P, Wade TD, Ure S, Johnson AR, Gill C, et al. Unguided low intensity cognitive behavior therapy for anxiety and depression during covid-19 pandemic: A randomised trial. Behav Res Ther. 2021; 144:103902.[DOI:10.1016/j.brat.2021.103902] [PMID]
26. McInerney J, Brown P, Bird JC, Nickless A, Brown G, Freeman D. Dose raising heart rate prior to a behavioural test enhance learning in cognitive therapy for anxiety? An experimental test for treatment of fear of heights using virtual reality. Behav Res Ther. 2021; 144:103928. [DOI:10.1016/j.brat.2021.103928] [PMID]