Claes Andersson
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Claes Andersson has a total of 278 co-authors. Here are the top co-authors by number of shared publications:
- Anne H. Berman
Department of Psychology, Uppsala University, Uppsala, Sweden
18 shared publications - Marcus Bendtsen
Department of Health, Medicine and Caring Sciences, Linkoping University, Linkoping, Östergötland, Sweden
10 shared publications - Olof Molander
Karolinska Institutet & Stockholm Health Care Services
8 shared publications - Petra Lindfors
Department of Psychology, Stockholm University, Stockholm, Sweden
8 shared publications - Naira Topooco
Department of Psychology, Uppsala University, Uppsala, Sweden
6 shared publications - Angel Y. Wang
University of British Columbia
5 shared publications
Latest Publications
- Open Access
- 29 October 2026
- Published by Elsevier in SSM - Mental Health
- Vol. 10
A social-ecological analysis of psychological self-management among college students
- 29 October 2026
- Published by Elsevier in SSM - Mental Health
- Vol. 10
Open AccessA social-ecological analysis of psychological self-management among college students
- Open Access
- 27 May 2026
- Published by Wiley in International Journal of Methods in Psychiatric Research
- Vol. 35 (2) , e70080
High Prevalences of Current Mental Disorder Diagnoses Among University Students in Sweden: A Cross‐Sectional Study With Implications for Student Mental Health Services
Objectives: To establish diagnostic prevalences for common mental disorders among students at higher education institutions (HEI's) in Sweden. Methods: This was a cross‐sectional study assessing diagnostic prevalences for 17,948 students at 30‐day, 12‐month and lifetime timepoints, according to the Diagnostic and Statistical Manual, fifth edition (DSM‐5). Sample participants at 15 HEI's answered an online survey 2020‐2023 within the World Mental Health International College Student (WMH‐ICS) initiative. Diagnoses are reported for Major Depressive Disorder (MDD), Generalized Anxiety Disorder (GAD), Panic Disorder (PD), Bipolar Disorder (BD, any), Alcohol Use Disorder (AUD) and Substance Use Disorder (SUD). Multilevel logistic regression was used to estimate odds ratios in relation to diagnoses of any mental disorder. Results: Respondents (69.4% women, 25.5 mean age, range 18 to ≥ 36) reported 25.2%, 39.3% and 44.5% prevalences for any mental disorder at 30‐day, 12‐month and lifetime periods. Odds for any mental disorder were markedly higher for non‐binary students and those with non‐heterosexual orientation; odds were also higher for students aged 20–29 years, women, heterosexual individuals with same‐sex attraction and post‐pandemic respondents. Conclusions: The findings augment existing concern over student mental health. Student mental health services should expand menus for low‐threshold treatment interventions, to promote flourishing and resilience.
- 27 May 2026
- Published by Wiley in International Journal of Methods in Psychiatric Research
- Vol. 35 (2) , e70080
Open AccessHigh Prevalences of Current Mental Disorder Diagnoses Among University Students in Sweden: A Cross‐Sectional Study With Implications for Student Mental Health Services
Objectives: To establish diagnostic prevalences for common mental disorders among students at higher education institutions (HEI's) in Sweden. Methods: This was a cross‐sectional study assessing diagnostic prevalences for 17,948 students at 30‐day, 12‐month and lifetime timepoints, according to the Diagnostic and Statistical Manual, fifth edition (DSM‐5). Sample participants at 15 HEI's answered an online survey 2020‐2023 within the World Mental Health International College Student (WMH‐ICS) initiative. Diagnoses are reported for Major Depressive Disorder (MDD), Generalized Anxiety Disorder (GAD), Panic Disorder (PD), Bipolar Disorder (BD, any), Alcohol Use Disorder (AUD) and Substance Use Disorder (SUD). Multilevel logistic regression was used to estimate odds ratios in relation to diagnoses of any mental disorder. Results: Respondents (69.4% women, 25.5 mean age, range 18 to ≥ 36) reported 25.2%, 39.3% and 44.5% prevalences for any mental disorder at 30‐day, 12‐month and lifetime periods. Odds for any mental disorder were markedly higher for non‐binary students and those with non‐heterosexual orientation; odds were also higher for students aged 20–29 years, women, heterosexual individuals with same‐sex attraction and post‐pandemic respondents. Conclusions: The findings augment existing concern over student mental health. Student mental health services should expand menus for low‐threshold treatment interventions, to promote flourishing and resilience.
- Open Access
- 31 March 2026
- Published by Springer Nature in Addiction Science & Clinical Practice
- Vol. 21 (1) , 33
App-based skills training to reduce problem drinking among adult internet help-seekers: a double-blinded randomized controlled trial
Introduction: Problem drinking (PD), defined as hazardous or harmful drinking, constitutes a major health and economic burden worldwide. However, most individuals with PD typically remain untreated for many years as part of the “treatment gap” between prevalence and treatment access. The main objective of this study was to evaluate an unguided, app-based intervention for reducing alcohol consumption, compared to an information control app. Secondary analyses targeted motivation effects, subgroup differences in heavy drinking days, and the proportion of participants with excessive drinking. Methods: In this two-armed randomized controlled trial (RCT), Swedish-speaking adults seeking help for PD on the Internet were recruited via online ads ( n = 576). Eligible participants, defined as those who reported PD without significant comorbid conditions, were randomly assigned to one of two unguided interventions, either the “TeleCoach” app ( n = 293) or the information control app ( n = 283), and followed up via online questionnaires at six-, 12- and 26-weeks post-recruitment. Participants and researchers were blinded to group assignment at recruitment but not for outcome analyses. The primary outcome was the number of standard drinks consumed per week. Results: Participants reported drinking a mean of 28 (SD = 18) standard drinks per week at the baseline recruitment measure, and 65% of the participants reported a history of PD for over three years; only 7% of the participants reported less than a year of PD history. Only 26% of the participants had sought help before. A significant within-group reduction in alcohol consumption occurred in both conditions at the six-week follow-up (B = −10.57, SE = 0.83, 95% CI [−12.20, −8.94], p < 0.01; Cohen’s d = 0.69), sustained until the 26-week follow-up (B = −11.44, SE = 0.91, 95% CI [−13.23, −9.65], p < 0.01, Cohen’s d = 0.67), with no significant differences between the two groups. No adverse events were reported. Conclusions: The findings, although null, nonetheless supported app-based interventions’ feasibility and potential as a scalable digital approach for reaching individuals who have not previously sought help for PD. Trial registration: ClinicalTrials.gov as NCT03696888, Oct 5, 2018; analysis plan at https://osf.io/wxfqg , on Dec. 18, 2023 prior to analysis.
- 31 March 2026
- Published by Springer Nature in Addiction Science & Clinical Practice
- Vol. 21 (1) , 33
Open AccessApp-based skills training to reduce problem drinking among adult internet help-seekers: a double-blinded randomized controlled trial
Introduction: Problem drinking (PD), defined as hazardous or harmful drinking, constitutes a major health and economic burden worldwide. However, most individuals with PD typically remain untreated for many years as part of the “treatment gap” between prevalence and treatment access. The main objective of this study was to evaluate an unguided, app-based intervention for reducing alcohol consumption, compared to an information control app. Secondary analyses targeted motivation effects, subgroup differences in heavy drinking days, and the proportion of participants with excessive drinking. Methods: In this two-armed randomized controlled trial (RCT), Swedish-speaking adults seeking help for PD on the Internet were recruited via online ads ( n = 576). Eligible participants, defined as those who reported PD without significant comorbid conditions, were randomly assigned to one of two unguided interventions, either the “TeleCoach” app ( n = 293) or the information control app ( n = 283), and followed up via online questionnaires at six-, 12- and 26-weeks post-recruitment. Participants and researchers were blinded to group assignment at recruitment but not for outcome analyses. The primary outcome was the number of standard drinks consumed per week. Results: Participants reported drinking a mean of 28 (SD = 18) standard drinks per week at the baseline recruitment measure, and 65% of the participants reported a history of PD for over three years; only 7% of the participants reported less than a year of PD history. Only 26% of the participants had sought help before. A significant within-group reduction in alcohol consumption occurred in both conditions at the six-week follow-up (B = −10.57, SE = 0.83, 95% CI [−12.20, −8.94], p < 0.01; Cohen’s d = 0.69), sustained until the 26-week follow-up (B = −11.44, SE = 0.91, 95% CI [−13.23, −9.65], p < 0.01, Cohen’s d = 0.67), with no significant differences between the two groups. No adverse events were reported. Conclusions: The findings, although null, nonetheless supported app-based interventions’ feasibility and potential as a scalable digital approach for reaching individuals who have not previously sought help for PD. Trial registration: ClinicalTrials.gov as NCT03696888, Oct 5, 2018; analysis plan at https://osf.io/wxfqg , on Dec. 18, 2023 prior to analysis.
- Open Access
- 29 March 2026
- Published by Springer Nature in BMC Research Notes
- Vol. 19 (1)
University students’ interest in intervention research participation is associated with gender, age and symptoms of depression, general and social anxiety, panic disorder and self-harm
Objective: Research in the mental health field has focused on exploration and implementation of digital interventions both in research and society. However, demographic and mental health factors that may influence engagement with research on such interventions have not been explored. This study aims to investigate the relationship between demographics, signs of mental disorders, and interest in participating in an intervention study. Using data collected in the Swedish arm of the World Health Organization’s World Mental Health International College Student (WHO-WMH-ICS) initiative ( n = 9140), we conducted a multinomial logistic regression to assess relationships between these factors. Results: Older age, as well as female and non-binary gender identities, were factors significantly associated with increased interest in the intervention study. Treatment flags, indicating fulfilment of criteria for possible mental disorder diagnosis, were significantly associated with clear interest (“yes” response) in intervention research for five of the 15 treatment flags: depression, general anxiety, social anxiety, panic disorder and self-harm. Possible interest (“maybe” response) was also indicated for four of these, excluding general anxiety. These findings may facilitate a better-informed approach to recruiting student participants for treatment research, enhancing unbiased recruitment practices, reducing treatment gaps, and increasing engagement in digital intervention studies for improved mental health.
- 29 March 2026
- Published by Springer Nature in BMC Research Notes
- Vol. 19 (1)
Open AccessUniversity students’ interest in intervention research participation is associated with gender, age and symptoms of depression, general and social anxiety, panic disorder and self-harm
Objective: Research in the mental health field has focused on exploration and implementation of digital interventions both in research and society. However, demographic and mental health factors that may influence engagement with research on such interventions have not been explored. This study aims to investigate the relationship between demographics, signs of mental disorders, and interest in participating in an intervention study. Using data collected in the Swedish arm of the World Health Organization’s World Mental Health International College Student (WHO-WMH-ICS) initiative ( n = 9140), we conducted a multinomial logistic regression to assess relationships between these factors. Results: Older age, as well as female and non-binary gender identities, were factors significantly associated with increased interest in the intervention study. Treatment flags, indicating fulfilment of criteria for possible mental disorder diagnosis, were significantly associated with clear interest (“yes” response) in intervention research for five of the 15 treatment flags: depression, general anxiety, social anxiety, panic disorder and self-harm. Possible interest (“maybe” response) was also indicated for four of these, excluding general anxiety. These findings may facilitate a better-informed approach to recruiting student participants for treatment research, enhancing unbiased recruitment practices, reducing treatment gaps, and increasing engagement in digital intervention studies for improved mental health.
- Open Access
- 15 January 2026
- Published by JMIR Publications Inc. in JMIR Formative Research
- Vol. 10, e68698
Personalized Transdiagnostic Cognitive Behavior Therapy With Midtreatment Stepped Care to Improve Mental Health Among University Students in Sweden: Feasibility Study for a Randomized Controlled Trial
Background: University students show a high prevalence of diverse mental health problems, requiring adaptable interventions to assist them in improving their mental health. Objective: This study aimed to evaluate the feasibility of transdiagnostic internet-delivered cognitive behavioral therapy (ICBT) for anxiety and depression in preparation for a randomized controlled trial. ICBT incorporated 2 innovative approaches to increase precision: user-steered content personalization and within-treatment adaptive modification based on early symptom trajectory. Methods: This single-group, open-label study was conducted online in Sweden in the autumn of 2021, recruiting from students who had completed the World Health Organization (WHO) World Mental Health International College Student (WMH-ICS) mental health survey. Participants were eligible if they scored 5-19 on the Patient Health Questionnaire-9 (PHQ-9), or ≥5 on the Generalized Anxiety Disorder-7 (GAD-7), or both. Participants completed an 8-week ICBT program with therapist support. They initially personalized their program by selecting a primary problem orientation, anxiety or depression, and choosing additional elective modules, and could consult their therapist regarding these choices. At midtreatment, stepped care was piloted, in which participants without symptom improvement were randomized to adaptive enhancement of therapist support or to continue treatment as before. The main feasibility outcomes included data on reach and uptake, intervention acceptability, stepped care procedures, and assessment retention up to 6 months. The GAD-7 and PHQ-9 were the primary outcome measures, with changes in scores calculated using mixed effects models. Results: Of 749 invited students, 55 (7%) completed the study screening, and 28 (4%) were included. The GAD-7 baseline score was 9.5 (SD 4.4), and the PHQ-9 baseline score was 11.2 (SD 5.2). Participants opened 6.2 (SD 2.2) out of the 8 treatment modules. The user-directed personalization yielded 27 unique treatment configurations across 28 participants. At week 4, 16/27 (59%) participants remaining in treatment were randomized in the stepped care procedure. Ratings on self-report measures showed acceptable to good therapeutic alliance and treatment satisfaction. Eleven participants reported increased stress associated with the treatment. Reductions in depression and anxiety symptoms were observed at postmeasurement and 6 months follow-up, with 43% attrition at those times. Conclusions: This pioneering study of personalized ICBT with adaptive change among university students demonstrated the overall feasibility of the treatment. To enhance the design of a future definitive trial, modifications are necessary to mitigate assessment attrition and reduce treatment-related stress. Trial Registration: ClinicalTrials.gov NCT05509660; https://clinicaltrials.gov/study/NCT05509660
- 15 January 2026
- Published by JMIR Publications Inc. in JMIR Formative Research
- Vol. 10, e68698
Open AccessPersonalized Transdiagnostic Cognitive Behavior Therapy With Midtreatment Stepped Care to Improve Mental Health Among University Students in Sweden: Feasibility Study for a Randomized Controlled Trial
Background: University students show a high prevalence of diverse mental health problems, requiring adaptable interventions to assist them in improving their mental health. Objective: This study aimed to evaluate the feasibility of transdiagnostic internet-delivered cognitive behavioral therapy (ICBT) for anxiety and depression in preparation for a randomized controlled trial. ICBT incorporated 2 innovative approaches to increase precision: user-steered content personalization and within-treatment adaptive modification based on early symptom trajectory. Methods: This single-group, open-label study was conducted online in Sweden in the autumn of 2021, recruiting from students who had completed the World Health Organization (WHO) World Mental Health International College Student (WMH-ICS) mental health survey. Participants were eligible if they scored 5-19 on the Patient Health Questionnaire-9 (PHQ-9), or ≥5 on the Generalized Anxiety Disorder-7 (GAD-7), or both. Participants completed an 8-week ICBT program with therapist support. They initially personalized their program by selecting a primary problem orientation, anxiety or depression, and choosing additional elective modules, and could consult their therapist regarding these choices. At midtreatment, stepped care was piloted, in which participants without symptom improvement were randomized to adaptive enhancement of therapist support or to continue treatment as before. The main feasibility outcomes included data on reach and uptake, intervention acceptability, stepped care procedures, and assessment retention up to 6 months. The GAD-7 and PHQ-9 were the primary outcome measures, with changes in scores calculated using mixed effects models. Results: Of 749 invited students, 55 (7%) completed the study screening, and 28 (4%) were included. The GAD-7 baseline score was 9.5 (SD 4.4), and the PHQ-9 baseline score was 11.2 (SD 5.2). Participants opened 6.2 (SD 2.2) out of the 8 treatment modules. The user-directed personalization yielded 27 unique treatment configurations across 28 participants. At week 4, 16/27 (59%) participants remaining in treatment were randomized in the stepped care procedure. Ratings on self-report measures showed acceptable to good therapeutic alliance and treatment satisfaction. Eleven participants reported increased stress associated with the treatment. Reductions in depression and anxiety symptoms were observed at postmeasurement and 6 months follow-up, with 43% attrition at those times. Conclusions: This pioneering study of personalized ICBT with adaptive change among university students demonstrated the overall feasibility of the treatment. To enhance the design of a future definitive trial, modifications are necessary to mitigate assessment attrition and reduce treatment-related stress. Trial Registration: ClinicalTrials.gov NCT05509660; https://clinicaltrials.gov/study/NCT05509660
- 11 June 2025
- Published by Elsevier in Psychiatry Research
- Vol. 351, 116585
Childhood adversities and their associations with mental disorders in the World Mental Health International College Student surveys initiative
- 11 June 2025
- Published by Elsevier in Psychiatry Research
- Vol. 351, 116585
Childhood adversities and their associations with mental disorders in the World Mental Health International College Student surveys initiative
- Open Access
- 22 May 2025
- Published by Elsevier in Psychiatry Research
- Vol. 350, 116555
The associations of childhood adversities and mental disorders with suicidal thoughts and behaviors - Results from the World Mental Health International College Student Initiative
- 22 May 2025
- Published by Elsevier in Psychiatry Research
- Vol. 350, 116555
Open AccessThe associations of childhood adversities and mental disorders with suicidal thoughts and behaviors - Results from the World Mental Health International College Student Initiative
- Top Cited Papers
- 18 April 2025
- Published by Elsevier in Journal of Psychiatric Research
- Vol. 186, 331-340
Mental disorders and sexual orientation in college students across 13 countries of differing levels of LGBTQ+ acceptance
- 18 April 2025
- Published by Elsevier in Journal of Psychiatric Research
- Vol. 186, 331-340
Top Cited PapersMental disorders and sexual orientation in college students across 13 countries of differing levels of LGBTQ+ acceptance
- Top Cited Papers
- 18 February 2025
- Published by Elsevier in Journal of Psychiatric Research
- Vol. 183, 225-236
Prevalence, age-of-onset, and course of mental disorders among 72,288 first-year university students from 18 countries in the World Mental Health International College Student (WMH-ICS) initiative
- 18 February 2025
- Published by Elsevier in Journal of Psychiatric Research
- Vol. 183, 225-236
Top Cited PapersPrevalence, age-of-onset, and course of mental disorders among 72,288 first-year university students from 18 countries in the World Mental Health International College Student (WMH-ICS) initiative
- Open Access
- 30 December 2024
- Published by Springer Nature in International Journal of Behavioral Medicine
- Vol. 33 (3) , 452-460
Non-compliance with COVID-19 Health Recommendations: Five- and Ten-Month Effects on Mental Health and Academic Self-efficacy Among University Students in Sweden
Background: Addressing the effects of non-compliance with health-related recommendations in pandemics is needed for informed decision-making. This longitudinal study investigated the effects of non-compliance on mental health and academic self-efficacy among university students in Sweden. Methods: Baseline assessments were conducted in May 2020, with follow-ups after 5 and 10 months. Students ( n = 3123) from 19 universities completed online questionnaires covering compliance, mental health, and academic self-efficacy. Effects of non-compliance were estimated using causal inference and multilevel multinomial regression. Results: Non-compliant students constituted a minority, but their proportion increased over time. Regarding mental health and academic self-efficacy, few differences were observed between compliant and non-compliant students. When differences were identified, non-compliant students experienced fewer negative effects on mental health and academic self-efficacy than compliant students. Conclusion: The findings may suggest that non-compliance may have involved a trade-off between increased individual freedom and mitigating negative outcomes. Addressing the research gap on non-compliance effects is crucial for informed decision-making and promoting the common good. This may guide strategies balancing individual autonomy and collective well-being during future pandemics. Pre-registration: Center for Open Science (OSF), https://accounts.osf.io/login?service=https://osf.io/37dhm/ .
- 30 December 2024
- Published by Springer Nature in International Journal of Behavioral Medicine
- Vol. 33 (3) , 452-460
Open AccessNon-compliance with COVID-19 Health Recommendations: Five- and Ten-Month Effects on Mental Health and Academic Self-efficacy Among University Students in Sweden
Background: Addressing the effects of non-compliance with health-related recommendations in pandemics is needed for informed decision-making. This longitudinal study investigated the effects of non-compliance on mental health and academic self-efficacy among university students in Sweden. Methods: Baseline assessments were conducted in May 2020, with follow-ups after 5 and 10 months. Students ( n = 3123) from 19 universities completed online questionnaires covering compliance, mental health, and academic self-efficacy. Effects of non-compliance were estimated using causal inference and multilevel multinomial regression. Results: Non-compliant students constituted a minority, but their proportion increased over time. Regarding mental health and academic self-efficacy, few differences were observed between compliant and non-compliant students. When differences were identified, non-compliant students experienced fewer negative effects on mental health and academic self-efficacy than compliant students. Conclusion: The findings may suggest that non-compliance may have involved a trade-off between increased individual freedom and mitigating negative outcomes. Addressing the research gap on non-compliance effects is crucial for informed decision-making and promoting the common good. This may guide strategies balancing individual autonomy and collective well-being during future pandemics. Pre-registration: Center for Open Science (OSF), https://accounts.osf.io/login?service=https://osf.io/37dhm/ .