Soc Psychiatry Psychiatr Epidemiol (2009) 44:1–7
DOI 10.1007/s00127-008-0400-7
ORIGINAL PAPER
Malin Gren-Landell Æ Maria Tillfors Æ Tomas Furmark Æ Gunilla Bohlin Æ Gerhard Andersson Carl Go¨ran Svedin
Social phobia in Swedish adolescents Prevalence and gender differences
Received: 22 January 2008 / Accepted: 10 June 2008 / Published online: 29 July 2008
j Abstract Background The aim of this study was to investigate the prevalence of self-reported social phobia in a community sample of Swedish adolescents in junior high school, at the risk-period for developing social phobia. Of particular interest was to investigate gender differences in prevalence across ages. Prevalence of sub-threshold social phobia was also studied. Methods Students in grades 6–8 (aged 12–14) from seventeen schools in five Swedish municipalities were screened by means of a self-report questionnaire, the social phobia screening questionnaire-for children (SPSQ-C). Results Data from a sample of 2,128 students were analysed and showed a point-prevalence rate of 4.4% (95%CI 3.5–5.2) and a significant gender
M. Gren-Landell, MSc (&) Æ C.G. Svedin Dept. of Clinical and Experimental Medicine Division of Child and Adolescent Psychiatry Linko¨ping University 581 85 Linko¨ping, Sweden Tel.: +46-13/224-202 Fax: +46-13/224-234 E-Mail:
[email protected] M. Tillfors Dept. of Behavioural, Social and Legal Sciences ¨ rebro University O ¨ rebro, Sweden O T. Furmark Æ G. Bohlin Dept. of Psychology Uppsala University Uppsala, Sweden G. Andersson Dept. of Behavioural Sciences and Learning The Swedish Institute for Disability Research Linko¨ping University Linko¨ping, Sweden
j Key words prevalence – social phobia – adolescents – gender
Introduction Social phobia, or social anxiety disorder, is described in the DSM-IV [3] as a marked and persistent fear of one or more social and performance situations in which embarrassment may occur. Exposure to unfamiliar people or possible scrutiny of others typically evokes anxiety and tends to be avoided or endured under great distress. Social phobia is argued to exist on a continuum, varying in severity and number of feared situations [19]. Lifetime prevalence rates of social phobia range from 3.9–13.7% in Western societies [17, 19, 23, 24, 32]. The notable variation in prevalence can largely be explained by methodological factors in addition to true cultural differences [19]. Lifetime prevalence rates of DSM-III-R and DSMIV defined social phobia in community samples of children and adolescents also vary considerably,
SPPE 400
G. Andersson Dept. of Clinical Neuroscience Karolinska Institutet Stockholm, Sweden
difference (6.6% girls vs. 1.8% boys, P < 0.001). No significant differences in prevalence of probable cases emerged across the ages. At sub-threshold level, marked social fear of at least one social situation was reported by 13.8% of the total group. ‘‘Speaking in front of class’’ and ‘‘calling someone unfamiliar on the phone’’ were the most feared social situations. In the social phobia group, 91.4% reported impairment in the school-domain due to their social fear. Conclusion Social phobia is a common psychiatric condition in Swedish adolescents, especially in girls. As impairment in the school-domain is reported to a high degree, professionals and teachers need to recognize social phobia in adolescents so that help in overcoming the difficulties can be offered.
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ranging from 0.9 to 13.1% [26]. The highest rates have been noted in studies of older adolescents and young adults [14, 24, 27, 36, 41, 44]. Onset of social phobia is reported to be in early- to mid-adolescence with a median age ranging from 12 to 16.6 years [8, 11, 17, 34], thus starting earlier in life compared to most other mental disorders [23]. Earlier onset is associated with a higher number of social fears [32] and with fear of more than one social- or performance situation, typical for the generalized subtype of social phobia [44]. Time of onset and the higher prevalence seen in adolescents compared to children can be associated with various aspects of cognitive maturation, e.g. an increased ability to take others viewpoints. While this ability is useful, it can also mean that the adolescent becomes more aware of others’ attention and the social evaluation and the opinions of peers might cause distress in some individuals [6]. Other explanations for the higher rates in adolescents compared to children could be increasing academic and social demands and encounters with a wider range of social situations [30]. During the teenage years it becomes more important to be part of a group and the risk of being excluded from the social group can be perceived as particularly distressing during this period [6]. In adult populations, a majority of studies report a female preponderance of social phobia as well as subthreshold social phobia [9–11, 24, 34]. The gender ratio seems to vary somewhat across different levels of social anxiety [13]. Although not as extensively studied, older adolescents show similar patterns as adults [14, 31, 41, 44]. Social phobia is associated with serious negative consequences, such as impaired quality of life and socio-economic disadvantages [17, 36]. Considerable impairment and distress have also been noted in subthreshold social phobia, i.e. individuals reporting excessive social anxiety without meeting the full diagnostic criteria for social phobia [13, 16]. It can therefore be argued that sub-clinical levels of the disorder deserve more attention from researchers and clinicians. Moreover, as there is no exact diagnostic threshold for social phobia, epidemiological research may benefit from studying prevalence rates across different levels of impairment and distress [19]. Most of the published prevalence studies on social phobia have been conducted on adult samples in Western but non-European countries [17]. There is to date no published study on the prevalence of social phobia in Swedish adolescents. The only Scandinavian study so far is a report on social phobia among Finnish children in the ages of 8- to 9 years with an estimated prevalence of 0.1% [1]. Reports on mental health in the Swedish general population and in other countries during the last decades, show an increase of internalizing symptoms such as anxiety and depression, in all age-groups and for both genders [33]. These symptoms are however more common among
adolescent girls [33]. Increasing female excess in general psychological distress is reported from the age of eleven to fifteen [38]. Given the reports of increasing mental health problems, especially in girls and the shortage of studies, there is a need for European studies on the prevalence of social phobia and gender differences in samples under the age of sixteen [43]. Thus, the aim of the present study was to examine the prevalence of social phobia, and sub-threshold social phobia, among Swedish adolescents in early- to mid-adolescence, at the typical period for onset for this disorder. In light of the female preponderance in adult community samples, we expected girls to report social phobia to a higher degree than boys. We also expected an increase in prevalence rates to appear over the ages as higher rates are seen in studies of older adolescents.
Method j Subjects Students from 17 comprehensive schools in five Swedish municipalities participated. The total sample consisted of 3,037 students in grades 6–8. In the Swedish school-system students enter school at the age of 6 years. Thus, students in grade 6 are normally at the ages of 11–12 years, grade 7 in the ages of 12–13 and students in grade 8 are normally in the ages of 13–14. A total of 1,104 boys, (47.1%) and 1,241 girls (52.9%) agreed to participate, resulting in an acceptable response rate of 77%. Reasons for not responding could be absence from school or disagreement to participate. Data from the non-responders were not collected. The response rate according to grade was 82% out of 1,005 students in grade six, 77% out of 888 students in grade seven and 79% out of 1,144 students in grade eight. The response rate ranged from 73–87% in the five municipalities. Due to incompletely filled out questionnaires, final data for analysis consisted of 2,128 respondents (992 boys, 46.6% and 1,136 girls, 53.4%) aged 11–15 years with a mean age of 13.1 years. None of the responders with incomplete questionnaires reported much distress in the phobic situations covered and thus they would not have been diagnosed with social phobia if included.
j Procedure The schools were recruited from five municipalities which were representative of the Swedish population by socio-economic composition such as gender distribution, proportion of inhabitants of foreign origin, proportion of inhabitants under the age of 17 and proportion of marriages [35]. Three municipalities were mediumsized (20–50.000 inhabitants, i.e. Na¨ssjo¨, Va¨rnamo and Va¨stervik), and two were large-sized (50–200.000 inhabitants, i.e. Jo¨nko¨ping and Linko¨ping) according to Swedish demographics [35]. Twelve of the seventeen schools were situated in medium-sized municipalities and five schools in large-sized. The schools were recruited to obtain a representative sample of schools with small, medium and large number of students and with small, medium and large number of students from families of foreign origin. Data collection took place in 2005. The study was approved by the Central Ethics Committee concerning Human Research in Sweden. Parents and students were given written information administered by the school-staff. Participation was voluntary and parents could contact the principal investigator in case they did not want their child to participate (n = 31). Students were also informed
3 about the voluntary investigation directly in the classroom either by a person from the project or by the teacher who had been given written information to read for the students. The questionnaire was administered to the students in their classroom.
j Questionnaire A DSM-IV [3] diagnosis of social phobia (probable case) was established by means of the Social Phobia Screening Questionnaire for Children (SPSQ-C), which is a modified version of the social phobia screening questionnaire (SPSQ) [20]. The SPSQ has been used in adult studies [7, 20, 39]. Psychometric evaluation of the SPSQ-C has shown a test–retest of r = 0.60 over 3 weeks, and a sensitivity of 71% and specificity of 86% (unpublished data) in relation to SCID-I [18]. In the present study, the eight phobic situations in the SPSQ-C had an alpha coefficient of 0.78 reflecting an acceptable internal consistency. The diagnostic section of the SPSQ-C was based on 8 potentially phobic situations. These situations were: ‘‘speaking in front of the class’’, ‘‘raising your hand during a lesson’’, ‘‘being together with others during breaks’’, ‘‘initiating a conversation with someone unfamiliar’’, ‘‘looking someone in the eyes during a conversation’’, ‘‘making a phone-call to someone unfamiliar’’, ‘‘going to a party’’, and lastly ‘‘eating together with others during the lunch-break’’. The respondent rated their perceived social fear in these potentially phobic situations on a three-point scale ranging from no fear, or some fear to marked fear. Five diagnostic questions followed, assessing whether the individual met the DSM-IV social phobia criteria A, B and D for one or more of the phobic situations. Since the youths were below 18 years old the C-criteria, realizing that the fear is excessive or unreasonable, did not have to be fulfilled. The Ecriterion was assessed with three yes/no questions, i.e. the student was asked whether the social fear was of such nature that it severely interfered with or severely interfered with his/her activities in school, during leisure-time or when being with peers. The eighth and last question covered the F-criterion of 6-month duration (yes/ no question).
j Diagnostic issues For a probable diagnosis of social phobia, the student had to rate at least one potentially phobic situation as marked fear on the social fear scale. This particular situation had to be consistently endorsed in the diagnostic questions covering social phobia criteria A, B and D. The E-criterion had to be met, i.e the report of impairment in at least one of the three life domains assessed. Lastly, the F-criterion, Table 1 Point-prevalence rates (%) of DSM-IV social phobia (probable cases) by gender among Swedish adolescents and summary results of logistic regression presented with odds ratios (OR) and P-values
Grade (age)
6 (11–12)a 7 (12–13)a 8 (13–14)a Total Grand total a
Gender (n)
Boys (226) Girls (290) Total (516) Boys (401) Girls (407) Total (808) Boys (365) Girls (439) Total (804) Boys (992) Girls (1,136) 2,128
concerning persistence of symptoms for more than 6 months, also had to be fulfilled. Four cut-off levels were chosen for measuring sub-clinical levels of social phobia. The first level concerned marked fear in at least one social situation on the first item of SPSQ-C. The second level concerned marked fear in at least one social situation and impairment in one life-domain. On the third level all criteria for social phobia except the 6-month duration (criteria A–E) were to be fulfilled and on the highest level, all criteria (A–F) for social phobia according to DSM-IV (criteria A–F) had to be fulfilled.
j Statistical analyses Prevalence rates are displayed as point prevalence with 95% confidence intervals (CI). For categorical variables, group differences were evaluated by use of v2 tests. Logistic regression was used in order to assess the increased odds of presenting with social phobia in relation to gender. Grade was used as a covariate when calculating odds ratios for gender. All analyses were performed in SPSS version 14.0 (SPSS, Inc., Chicago, IL, USA). Grade was used as variable instead of age due to small numbers in the youngest agegroup (aged 11) and the oldest (aged 15). This was also motivated by the notion that students from the same grade might be more similar with regard to psychological maturation and environmental demands as compared to students of the same age but in different grades.
Results j Prevalence of social phobia The proportions of respondents fulfilling the DSM-IV criteria of social phobia (probable cases) are presented in Table 1 for gender and for grade separately. In the total group, a point-prevalence of 4.4% (95%CI = 3.5–5.2) was found. A significant gender difference was found in the total group, and for each grade, with higher prevalence of social phobia in girls than in boys (see Table 1). There was no significant difference in prevalence between the grades neither in the total group (v2 = 1.69, df = 2, NS) nor when analysed separately Social phobia n (%)
(95%CI)
OR (95%CI)
P
3 18 21 8 23 31 7 34 41 18 75 93
(0.2–2.8) (3.4–9.0) (2.4–5.8) (0.6–3.4) (3.4–8.0) (2.4–5.8) (0.5–3.3) (5.2–10.3) (3.6–6.6) (1.0–2.6) (5.2–8.0) (3.5–5.2)
4.20 (1.43–16.91)b
