Abstract
Family cohesion, known as the quality of interactions among family members, plays a pivotal role in the health and optimal functioning of the family system.Therefore, the aim of the present study was to investigate the psychometric properties of the Persian version of the Family Cohesion Scale(FCS) among Iranian parents.The present research method was quantitative-descriptive.The statistical population included all parents of primary school students in District 5 of Tehran in the academic year 2023-2024.From this population, 336 individuals were selected via convenience sampling and completed the questionnaires. Participants completed the Persian version of the Family Cohesion Scale(FCS), along with the Triangulation Scale(TS), the Emotional Blackmail Scale(EBS), the Marital Interactional Stability Scale(MISS), and the Marital Intimacy Scale(MIS).To examine construct validity,Confirmatory Factor Analysis(CFA) was used. Convergent and divergent validity were assessed using Pearson's correlation coefficient.The reliability of the instrument was evaluated using internal consistency based on Cronbach's alpha coefficient and the split-half method.The results of the confirmatory factor analysis indicated a good fit and adequacy of the three-factor model.Significant correlations between family cohesion and marital interaction and marital intimacy confirmed the convergent validity of the scale.Similarly, significant negative correlations with triangulation and emotional blackmail confirmed its divergent validity.The estimated total reliability coefficients from the Spearman-Brown and Guttman formulas, along with the overall internal consistency of the scale and its subscales, indicated appropriate reliability for this scale.Given the favorable psychometric properties of the Persian version of the Family Cohesion Scale, it can be used as a reliable instrument in the population of Iranian parents.

Introduction
Family cohesion, defined as the quality of interactions among family members, plays a pivotal role in the health and optimal functioning of the family system. In many cultures, the family serves as the primary source of support, affection, attachment, and socialization for individuals (Mohagheghi & Roshanaei, 2023). Each family member possesses a unique personality, attitudes, emotions, thoughts, and beliefs, making the family a complex and cohesive unit that significantly influences members' mental health and well-being (Sadeghi et al., 2022). Establishing healthy relationships among members and maintaining balance and boundaries within the family is directly linked to both physical and psychological health (Tsoutsi & Dikeos, 2024).
Within this complex relational context, family cohesion emerges as a key factor in achieving health and well-being (Favez et al., 2024). Family cohesion, recognized as the quality of triadic interactions among father-mother-child (Deschenes et al., 2023), reflects family members' capacity for effective cooperation and coordination in various everyday situations. It represents an important indicator of family health and unity, referring to the emotional bond among family members that strengthens feelings of belonging, support, and unity (Goodrum et al., 2020).
According to the Family Alliance Model, the family is not merely a collection of dyadic relationships but a triadic interactive system whose functional quality is manifested in the degree of coordination among members during joint activities. Family cohesion refers to members' ability to organize interactions, maintain shared goals, fulfill complementary roles, and share emotions. This concept extends beyond cohesion or emotional intimacy to explain the quality of coordinated family functioning in daily interactions, encompassing four interactive functions: participation, organization, focusing, and emotional sharing, arranged hierarchically (Favez et al., 2017).
Despite the importance of family cohesion in promoting mental health and well-being, research conducted in Iran has primarily focused on the positive relationship between cohesive family environments and favorable outcomes. While several instruments exist for measuring family functioning and cohesion, the psychometric properties of the Persian version of the Family Cohesion Scale have not been previously examined. Therefore, the present study aimed to investigate the psychometric properties of the Persian version of the Family Cohesion Scale (FCS) among Iranian parents.

Research Methodology
The present study employed a quantitative-descriptive research design. The statistical population included all parents of primary school students (grades 1-3) in District 5 of Tehran during the academic year 2024-2025. A total of 350 parents (175 males, 175 females) were selected via convenience sampling; after excluding 14 incomplete questionnaires, the final sample comprised 336 participants (168 males, 168 females) with a mean age of 36.29 years (SD = 2.42).
Participants completed the Persian version of the Family Cohesion Scale (FCS; Tsoutsi & Dikeos, 2024), along with the Triangulation Scale (TS; Bahrami & Yousefi, 2012), the Emotional Blackmail Scale (EBS; Karnani, 2018), the Marital Interactional Stability Scale (MISS; Gottman, 1999), and the Marital Intimacy Scale (MIS; Walker & Thompson, 1983).
Construct validity was examined using Confirmatory Factor Analysis (CFA). Convergent and divergent validity were assessed through Pearson's correlation coefficients. Reliability was evaluated using internal consistency (Cronbach's alpha) and the split-half method (Spearman-Brown and Guttman formulas). Content validity was established through expert judgment by 19 specialists using the Lawshe method, with all items demonstrating Content Validity Ratios above the acceptable threshold of 0.42.

Discussion
Factor Structure and Construct Validity
The results of the present study demonstrated that the Persian version of the Family Cohesion Scale possesses favorable psychometric properties, confirming its three-dimensional structure in the Iranian parent sample. This finding aligns with the results of Sánchez and Ibarra (2026), Alrajhi et al. (2025), and Tsoutsi and Dikeos (2024), who validated this scale in international samples, indicating that the conceptual structure of this construct is replicable within the Iranian cultural context.
Confirmatory Factor Analysis (both first-order and second-order) confirmed the three-factor structure of the scale. The confirmation of three dimensions—Communication, Anger/Resentment/Aggression, and Values and Beliefs—indicates that family cohesion in the Iranian cultural context is a multidimensional construct shaped by the simultaneous interaction of communicative, emotional, and cognitive aspects. The Communication factor reflects family members' ability to effectively exchange information, engage in active listening, solve problems, and coordinate daily interactions, forming the foundation for cooperation and mutual trust. The Anger/Resentment/Aggression factor reflects not merely the presence of conflict but the quality of emotional regulation and conflict management, suggesting that in families with high cohesion, conflicts are managed constructively rather than escalating into persistent aggression and hostility. Finally, the Values and Beliefs factor represents shared cognitive and value frameworks among family members that foster cohesion in decision-making, planning, and a sense of familial belonging.
From the perspective of family systems theory, the interaction of these three dimensions creates the conditions for overall harmony and effective family functioning, such that weakness in any dimension can affect family cohesion (Tsoutsi & Dikeos, 2024; Minuchin, 2018). The confirmation of the second-order factor structure, indicating a more general construct called "family cohesion," demonstrates that despite conceptual distinctiveness, these dimensions contribute to a coherent and integrated whole under the overarching concept of family cohesion. The satisfactory fit of both models provides strong support for the accuracy of the measurement structure, indicating appropriate construct validity.
Conceptual Distinctiveness from Family Cohesion
The findings also reveal that while family cohesion overlaps with concepts such as family cohesion (in the traditional sense) and family functioning, it is not synonymous with them. Whereas family cohesion (traditional) primarily emphasizes emotional bonds, belonging, and closeness among family members, the three-dimensional structure of this scale encompasses dimensions beyond cohesion, including communication quality, conflict management, and shared family values and beliefs. Thus, the construct measured by this instrument reflects not merely family cohesion but the quality of harmony and alignment in interactions among family members. For this reason, the Persian version adopted the title "Family Cohesion Scale" (Ettehad-e Khanevadeh) to better reflect the broader scope of the construct compared to the concept of mere family togetherness.
Convergent and Divergent Validity
Evidence for convergent and divergent validity further supported the quality of the measurement model. Convergent validity demonstrated strong positive correlations between the total score of family cohesion and all its dimensions with marital interaction stability and marital intimacy (r = 0.66 for both total scale correlations). These findings align with Roman et al. (2025), Daradka et al. (2024), and Ackerman et al. (2011). This result indicates that marital relationships serve as the cornerstone of overall family cohesion and bonding. According to family systems theory (Minuchin, 2018), the couple subsystem functions as the regulatory core of family relationships, and the quality of couple interactions shapes communication patterns for other family members. When couples possess appropriate communication skills, mutual support, and effective emotion regulation, this pattern generalizes to parent-child interactions, ultimately strengthening family cohesion.
Divergent validity revealed significant negative correlations between total family cohesion and all its dimensions with maladaptive constructs including triangulation and emotional blackmail. Subscale correlations with triangulation ranged from r = -0.62 (Communication) to r = -0.59 (Anger/Resentment/Aggression), while correlations with emotional blackmail ranged from r = -0.38 (Communication) to r = -0.56 (Anger/Resentment/Aggression). These findings align with Vera-Ruiz et al. (2026) and McCauley et al. (2021). This result confirms that family cohesion is not merely the absence of conflict but a positive, independent construct whose active presence prevents the formation of pathological communication patterns. The negative correlation with triangulation and emotional blackmail is particularly explicable by the nature of the Communication and Anger/Resentment/Aggression factors. In families with constructive communication patterns, conflicts are resolved directly between couples, reducing the need to involve children in marital disputes. Additionally, the ability to manage negative emotions prevents the use of controlling strategies such as emotional blackmail.
This pattern holds particular significance in the cultural context of Iranian families, which emphasize internal solidarity and cohesion, as it demonstrates that authentic family cohesion—even in a culture where close relationships are valued—does not necessarily imply unhealthy enmeshment or boundary violations but can provide a context for growth within a healthy framework.
Reliability
Reliability coefficients obtained through Cronbach's alpha indicated strong internal consistency for the total scale (α = 0.89) and acceptable-to-excellent consistency for subscales: Communication (α = 0.87, 6 items), Anger/Resentment/Aggression (α = 0.77, 4 items), and Values and Beliefs (α = 0.75, 3 items). The split-half method yielded Spearman-Brown and Guttman coefficients of 0.81 and 0.80, respectively, demonstrating satisfactory reliability. These findings indicate that the Persian translation has not only preserved conceptual meaning but maintained item homogeneity within the Iranian cultural context.

Conclusion
The present study, as one of the first systematic investigations into family cohesion assessment in the Iranian context, demonstrates that the Persian version of the Family Cohesion Scale is a valid and reliable instrument for assessing family interaction quality among Iranian parents. By focusing on communication quality, conflict management, and shared values, this instrument enables the assessment of a construct that extends beyond the mere concept of family cohesion, representing the coordination of the entire family system's functioning.
The validated scale can contribute to the development of local research, the design of family-centered interventions, and the evaluation of family relationship enhancement programs. However, caution should be exercised in generalizing results due to limitations including convenience sampling, lack of control over contextual variables such as socioeconomic status and education level, and the cross-sectional nature of the data. Future research is recommended to employ random national samples, longitudinal designs, and more comprehensive investigations into the relationships between family cohesion processes and variables such as parenting quality, adolescent resilience, and marital stability. Utilization of this scale for screening, designing educational interventions, and evaluating family support programs can represent a practical step toward strengthening Iranian families and provide a scientific foundation for evidence-based interventions in family counseling centers.