en خانواده و گروه درماني Family and group therapy پژوهشي Original Research Article <div style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:Tahoma;"><span style="line-height:2;"><b><span lang="EN-GB">Background and Objective</span></b><span lang="EN-GB">: Sexual behaviour is one of the most important developmental experiences in adolescence and may lead to long‑term consequences. This study aimed to compare the effectiveness of cognitive-behavioural therapy<b> </b>(CBT), parent-child interaction therapy<b> </b>(PCIT), and their combination on depression, family functioning, and parenting stress in adolescents with problematic sexual behaviours (PSBs).</span><br> <b><span lang="EN-GB">Method: </span></b><span lang="EN-GB"><span style="color:black">The sample consisted of<b> </b>35 female students (10-13 years old) with problematic sexual behaviours (PSBs) from schools in Guilan Province, Iran, during the 2023-2024 academic year. They were identified by purposive sampling and based on the Sexual Behaviour Checklist and a clinical interview and were randomly assigned (</span></span>using a table of random numbers)<span style="color:black"> to three experimental groups (two groups with 12 participants and one group with 11 participants). To measure the variables, </span><span lang="EN-GB">Maria Kovacs Children&#39;s Depression Questionnaire, Family Functioning Questionnaire, and Parenting Stress Scale were used. <span style="color:black">After completing the questionnaires, the treatment sessions began. The pretest, posttest design with three test groups was used, and data analysis was conducted using analysis of covariance (ANCOVA) with SPSS software (version 27).</span></span><br> <b><span lang="EN-GB">Results</span></b><span lang="EN-GB">: <span style="color:black">A statistically significant difference was observed among </span>the experimental groups for depression (F = 4.83, <i>df</i> = 2, <i>P</i> = 0.01,</span><span lang="EN-GB"> observed power</span><span lang="EN-GB"> [OP] = 0.78)</span> <span lang="EN-GB">and family functioning (F = 18.14, <i>df</i> = 2, <i>P</i> = 0.001, OP = 1.00).</span> <span lang="EN-GB">However, no significant difference was observed among experimental groups for parenting stress (F = 2.76, <i>df</i> = 2, <i>P</i> = 0.08). <span style="font-family:&quot;Times New Roman&quot;,serif"></span></span><br> <b><span lang="EN-GB">Conclusion: </span></b><span lang="EN-GB">According to the results, CBT-PCIT is more effective than CBT in reducing depression, and PCIT and CBT-PCIT are more effective than CBT for improving family functioning.</span></span></span></span></div> Parent-child interaction therapy (PCIT), Cognitive-behavioural therapy (CBT), Depression, Family function, Parenting stress, Problematic sexual behaviour (PSBs) 0 0 http://jpcp.uswr.ac.ir/browse.php?a_code=A-10-1028-3&slc_lang=en&sid=1 Fatemeh Mehrvarz taramehrvarz@webmail.guilan.ac.ir No Department of Psychology, Faculty of Literature and Humanities, University of Guilan, Rasht, Iran Abbas Abolghasemi abolghasemi1344@guilan.ac.ir Yes Department of Psychology, Faculty of Literature and Humanities, University of Guilan, Rasht, Iran Mahnaz Khosrojavid khosrojavid@guilan.ac.ir No Department of Psychology, Faculty of Literature and Humanities, University of Guilan, Rasht, Iran Abbas Ali Hossein Khanzadeh khanzadehabbas@guilan.ac.ir No Department of Psychology, Faculty of Literature and Humanities, University of Guilan, Rasht, Iran