Anonymous treatment for the prevention of child sexual abuse

<p dir="ltr">Background: Child sexual exploitation and abuse offenses are serious public health concerns associated with harm to victims, families and society. Prevention efforts have focused on detected and convicted offenders, although many individuals at risk of offending remain outside ordinary healthcare and criminal justice systems. Barriers such as shame, and fear of disclosure or legal consequences may prevent help-seeking among those with sexual urges toward children. There is therefore a need for accessible prevention interventions, time-sensitive self-report risk assessments, and adapted treatment approaches.</p><p dir="ltr">Aims: The overall aim of this thesis was to develop and evaluate a low-threshold secondary prevention pathway for help-seeking individuals concerned about sexual urges or behaviors involving children, by examining contextual risk factors, short-term self-reported risk assessment, and the effectiveness of Prevent It 2.0. Specific aims were to: (1) explore how anonymous help-seeking participants with recent child sexual abuse material (CSAM) use perceived the COVID-19 pandemic and associated restrictions to affect daily life, mental health, sexual thoughts and urges, offending-related behaviors, coping, and support needs; (2) evaluate the predictive ability of the Sexual Child Molestation Risk Assessment (SChiMRA/SChiMRA+) as a short-term indicator of heightened risk for sexual offending; (3) evaluate the effectiveness of the international English version of Prevent It 2.0; and (4) evaluate the effectiveness of the country-specific German, Swedish, and Portuguese versions of Prevent It 2.0.</p><p dir="ltr">Method: In Study I, semi-structured text-based interviews were conducted with 18 international male participants from the Prevent It 1.0 trial and analyzed using qualitative inductive content analysis. In Study II, self-reported longitudinal data from two clinical trials were analyzed using mixed-effects models and receiver operating characteristic analyses. The trials included Priotab, a pseudonymized medical trial including 52 men in Sweden with pedophilic disorder recruited via ANOVA, a specialist sexual medicine clinic at Karolinska University Hospital, and the Swedish PrevenTell helpline, and Prevent It 1.0, an 8-week anonymous internet-delivered cognitive behavioral therapy (iCBT) trial including 160 predominantly male participants reporting recent CSAM use, recruited internationally, mainly through darknet forums. In Studies III and IV, Prevent It 2.0, an updated 9-week anonymous iCBT, was evaluated in randomized waitlist-controlled trials using intent-to-treat mixed-effects regression models. Study III included 203 internationally recruited English-speaking participants concerned about sexual urges toward children. Study IV used the same design conducted in Germany, Sweden, and Portugal, and included 206 German-, Swedish-, and Portuguese-speaking participants. Both studies used online clearnet and darknet advertisements and professional referrals.</p><p dir="ltr">Results: In Study I, participants described increased loneliness, poorer mental health, reduced daily structure, and increased time online during the COVID-19 pandemic, often linked to increased sexual urges and CSAM use. Participants also described coping strategies such as increasing activity and support, and decreasing barriers to healthcare. In Study II, SChiMRA motivation items predicted corresponding self-reported sexual offending. In Priotab, motivation to watch CSAM, socialize with children, and sexually interact with children each predicted the corresponding same-time behavior. In Prevent It 1.0, motivation to watch CSAM predicted same-week CSAM use and next-week CSAM use, and motivation to interact with children also predicted same-week CSAM use. Additionally, a motivation-to-watch-CSAM cutoff of 4.5 identified same-week CSAM use with 83.7% sensitivity, 63.7% specificity, and AUC = .802, and next-week use with 83.0% sensitivity, 53.1% specificity, and AUC = .727. In Study III, Prevent It 2.0 was associated with reduced sexual urge severity (-6.41 S-SAS points, d = -1.01), time observing children for sexual purposes (which includes CSAM use) (-1.87 hours/week, d = -0.52), and COPINE severity (-1.56 points, d = -0.61). In Study IV, the clearest findings were observed in the German arm (n = 158), where Prevent It 2.0 reduced sexual urge severity, time observing children, and COPINE severity. The Swedish arm (n = 36) showed a similar but less precise pattern, while the Portuguese arm (n = 12) was underpowered and yielded limited findings. Findings across the full sample (N = 206) showed similar reductions in sexual urge severity, time spent observing children, and COPINE severity.</p><p dir="ltr">Conclusion: This thesis shows that a low-threshold secondary prevention pathway can be used for individuals concerned about sexual urges or behaviors toward children. Prevent It 2.0 was associated with reduced sexual urge severity and self-reported offending-related behaviors, supporting the value of accessible prevention services. Anonymous access, repeated self-reported risk assessment, and therapist-guided intervention may help lower barriers to help-seeking and support monitoring of short-term changes in risk. The findings also suggest that self-reported dynamic risk and motivation may provide clinically meaningful information about heightened risk, particularly for CSAM use.</p><h3 dir="ltr">List of scientific papers</h3><p dir="ltr">I. <b>McMahan, A.</b>, Roche, K., Dreyhaupt, R., Seto, M. C., & Rahm, C. (2023). Changes in sexual thoughts and behaviors in a clinical sample of child sexual abuse material users under the COVID-19 pandemic. Sexual and Relationship Therapy, 1-21. <a href="https://doi.org/10.1080/14681994.2023.2215710">https://doi.org/10.1080/14681994.2023.2215710</a></p><p dir="ltr">II. <b>McMahan, A.</b>, Luke, T. J., Andersson, G., Rahm, C., & Joleby, M. (2026). Predictive Ability of the Sexual Child Molestation Risk Assessment (SChiMRA+). Sexual Abuse, 38(4), 447-473. <a href="https://doi.org/10.1177/10790632261415813">https://doi.org/10.1177/10790632261415813</a></p><p dir="ltr">III. <b>McMahan, A.</b>, Joleby, M., Andersson, G., Letourneau, E., Seto, M., Luke, T., Rahm, C. (2026). An International Randomized Waitlist-Controlled Trial of Internet-Delivered Cognitive Behavioral Therapy for Sexual Urges Towards Children. (Manuscript accepted for publication). Journal of Consulting and Clinical Psychology. [Accepted]</p><p dir="ltr">IV. Maimone, S., Joleby, M., Haubrock, L., Rahm, C., Carvalho, J., Dekker, A., Letourneau, E., Hillert, J., Azevedo, V. C., <b>McMahan, A.</b>, Rodrigues, C., Bjurenfalk, Z., Zällh, S., Korkutan, T., Lätth, J., Luke, T. J., Andersson, G., Curry, S., Fix, R., Seto, M. C., & Briken, P. (2026). Effects of an internet-delivered, cognitive behavioral-based intervention on sexual urges toward children: A randomized waitlist-controlled trial in Germany, Sweden, and Portugal (Manuscript submitted for publication). Journal of Medical Internet Research. [Submitted]</p>