University of Tabriz Journal of Modern Psychological Researches 2322-3340 17 65 2022 05 22 Comparison of the Effectiveness of Choice Theory Approach and Acceptance and Commitment Approach on Emotional Processing, Self-Differentiation, Body Image and Body Fat Mass Index (FMI) in Overweight Women Comparison of the Effectiveness of Choice Theory Approach and Acceptance and Commitment Approach on Emotional Processing, Self-Differentiation, Body Image and Body Fat Mass Index (FMI) in Overweight Women 228 238 13664 10.22034/jmpr.2022.13664 FA Mahsa Ghorbani Ph.D. student in Health Psychology, Department of Psycholgy, Faculty of Education and Psycholgy, Payame Noor University, Tehran, Iran. Ezatolah Kordmirza Nikozadeh Associate Professor of Health Psychology, Department of Psycholgy, Faculty of Education and Psycholgy, Payame Noor University, Tehran, Iran. Ahmad Alipor Professor of Health Psychology, Department of Psycholgy, Faculty of Education and Psycholgy, Payame Noor University, Tehran, Iran. Journal Article 2021 09 06 Overweight is a psycho-physiological problem that is associated with a wide range of negative consequences and in addition to biological and physical risk factors, psychological factors also play an important role in its occurrence and exacerbation. The aim of this study was to compare the effectiveness of the choice theory approach and acceptance and commitment approach on emotional processing, self-differentiation, body image and body fat mass index (FMI) in overweight women. The method was quasi-experimental with three-group pretest-posttest design. The statistical population consisted of all overweight women in Tehran who referred to Tehran health centers in the first half of the year 1400 (N = 2417). Among them, several centers were randomly selected and from the selected centers, 36 people were selected based on the inclusion criteria and were randomly assigned to the three groups of Experiment 1, Experiment 2 and Control. The first experimental group received the intervention based on choice theory with Glasser (2010) approach in 12 sessions of 60 minutes, the second experimental group received acceptance and commitment therapy with Hayes et al (2013) approach in 12 60-minute sessions. The research instruments were Baker et al.'s (2010) Emotional Processing Scale, Tetleton et al.'s (2005) Tetris Questionnaire of Body Image. Data were analyzed by multivariate analysis of covariance and LSD post hoc test by SPSS25 software. The results showed that there was a significant difference between the experimental and control groups in the dimensions of repression, unpleasant emotional experience, emotional symptoms of processing, avoidance, emotional control, dissatisfaction and embarrassment of their appearance and body fat mass index. (p<0/05). The LSD post hoc test also showed that in order to improve the dimensions of emotional processing, the intervention based on choice theory was more effective than the treatment of acceptance and commitment. Based on the results of the present study, applying new third wave therapies can be effective in improving the psychological status of overweight women. Overweight is a psycho-physiological problem that is associated with a wide range of negative consequences and in addition to biological and physical risk factors, psychological factors also play an important role in its occurrence and exacerbation. The aim of this study was to compare the effectiveness of the choice theory approach and acceptance and commitment approach on emotional processing, self-differentiation, body image and body fat mass index (FMI) in overweight women. The method was quasi-experimental with three-group pretest-posttest design. The statistical population consisted of all overweight women in Tehran who referred to Tehran health centers in the first half of the year 1400 (N = 2417). Among them, several centers were randomly selected and from the selected centers, 36 people were selected based on the inclusion criteria and were randomly assigned to the three groups of Experiment 1, Experiment 2 and Control. The first experimental group received the intervention based on choice theory with Glasser (2010) approach in 12 sessions of 60 minutes, the second experimental group received acceptance and commitment therapy with Hayes et al (2013) approach in 12 60-minute sessions. The research instruments were Baker et al.'s (2010) Emotional Processing Scale, Tetleton et al.'s (2005) Tetris Questionnaire of Body Image. Data were analyzed by multivariate analysis of covariance and LSD post hoc test by SPSS25 software. The results showed that there was a significant difference between the experimental and control groups in the dimensions of repression, unpleasant emotional experience, emotional symptoms of processing, avoidance, emotional control, dissatisfaction and embarrassment of their appearance and body fat mass index. (p<0/05). The LSD post hoc test also showed that in order to improve the dimensions of emotional processing, the intervention based on choice theory was more effective than the treatment of acceptance and commitment. Based on the results of the present study, applying new third wave therapies can be effective in improving the psychological status of overweight women. https://psychologyj.tabrizu.ac.ir/article_13664_b9f1580256b6634a93315d59fa028f53.pdf