The SISA Scale is one of the most widely used instruments for measuring self-actualization. Given the need to investigate the psychometric properties of the instrument across cultures and samples (
33), this study aimed to verify the validity of the SISA in assessing self-actualization tendencies in a non-clinical Iranian population. The questionnaire was meticulously translated by knowledgeable and skilled individuals who adhered to translation guidelines, ensuring cultural compatibility. A notable strength of this study is its adherence to the four basic steps recommended in the translation process, which guarantees cultural adaptation of the scale (
34).
After ensuring the accuracy of translation and pre-application, validity (including construct validity through exploratory and CFA, and convergent and discriminant validity) and reliability were assessed using several methods. An EFA was initially performed to investigate the factor structure of the SISA in the Iranian sample, identifying five components with eigenvalues greater than one. The results of the CFA showed that the selected items were appropriate and that the questionnaire maintained its original structure with minimal changes. Therefore, it can be concluded that the cultural and ethnic differences and diverse experiences of the Iranian sample did not cause any differences in the scores of the SISA compared to other samples.
Overall, considering the fit and appropriateness of the five-factor model and the model’s compliance with CFA, the SISA is a suitable tool for measuring self-actualization tendencies and has acceptable validity for research purposes. The CFA further supported the construct validity of the scale, with a RMSEA of 0.062, where a value less than 0.08 indicates a good fit, a value between 0.08 and 0.10 indicates a moderate fit, and a value greater than 0.10 indicates a poor fit. Finally, this self-assessment questionnaire was validated with 15 questions and 5 main components that align with the findings of earlier research (
8,
14,
35).
Finally, this self-assessment questionnaire was validated with 15 questions and 5 main components that align with the findings of earlier research (
8,
14,
35). Autonomy and self-directedness (items 2, 5, 9, 10, 11, 13) are the needs for self-determination and the perception of having options in starting, continuing, and managing activities. When people believe they are in charge of their own behavior, they become autonomous. This indicates that they are able to make decisions with confidence and operate at their best based on internalized values and personal motivations (
36,
37). Self-acceptance and self-esteem (items 6, 8, 14) involve recognizing one’s strengths and weaknesses, enhancing strengths and addressing weaknesses, being comfortable with one’s current situation, lacking shame, and refraining from self-blame for shortcomings or errors (
38,
39). Self-actualization entails finding, expressing, and growing into your genuine self, which necessitates self-acceptance. Individuals that struggle with self-acceptance either deny or misrepresent who they really are (
2). The factor of acceptance of emotions and freedom to express emotions (items 1, 4) refers to being receptive and open to one’s inner world, thoughts, and physical feelings (
40). Self-actualization is a set of interpersonal and emotional capacities and skills that impact our behavior and communication with others. Furthermore, it enhances flexibility, enabling individuals to be more conscious and in touch with the present moment (
41). These abilities can serve as a foundation for emotional growth and foster self-actualization (
42).
Self-actualized persons have deeper and healthier interpersonal relationships than other people, as evidenced by the factors of trust and commitment in interpersonal interactions (items 3, 15) (
3). The ability to build intimacy with others without expectations or obligations is a basic human need that is met in interpersonal relationships. Among the most crucial social behaviors are trust and responsibility. Trust refers to the general tendency of people to take risks in interpersonal relationships, regardless of their ability to evaluate or control others (
43). Responsibility refers to people’s desire to trust and be loyal to others (
44,
45). Now consider the factor of the ability to cope with rather than avoid undesirable aspects of life (items 12, 7). Avoiding unpleasant experiences will prevent people from engaging in certain behaviors that they fear, and thus limit their lives, preventing them from learning and developing their talents and abilities. Rather, the ability to confront and overcome difficult and unfavorable situations changes the relationship with the inner self. This enhances flexibility and decision-making, helping people act according to their values and cope with new experiences and situations. They are able to recognize and fulfill their important life values and potentials through this process (
46).
A successful fit of the 5-factor model of the SISA is also shown by the fit indices of the model and the values derived from them. In addition, the internal consistency of the scale was evaluated using Cronbach’s alpha, and the results showed that there was a strong correlation between the items. This indicates that there was no measurement error in the scale and that respondents had relatively consistent perceptions of the scale. The results of the convergent validity of the entire scale showed a high positive correlation, which confirmed that this self-assessment scale had convergent validity for self-actualization. Furthermore, the results of the discriminant validity of SISA revealed weak but substantial negative correlations between the Ambiguity Tolerance Questionnaire and the components of SISA. This is different from the previous studies (
14,
47,
48) that found no significant relationship between these factors. In contrast, other researchers found a relationship between these variables (
49). As Maslow pointed out, self-actualized people appear to “not only tolerate ambiguity and unstructured situations, but also enjoy them” (
3). Previous studies have shown that tolerance for ambiguity is important for personality change and self-actualization (
49). This variable is considered a cognitive control style and represents the ability to cope with situations with ambiguous or unstructured stimuli (
50,
51). It is also related to various aspects of cognitive and emotional functioning, cognitive style traits, belief systems, attitudes, interpersonal and social functioning, and problem-solving behavior (
52). Individuals with high ambiguity tolerance find unclear circumstances interesting and challenging, and they frequently score higher on openness to experience (
53) and are more likely to take risks (
54).
In line with earlier studies, the study also discovered a strong positive correlation between the SISA and both rational behavior and self-esteem (
14,
51,
55). Goal achievement, interpersonal relationships, and self-focus are all correlated with self-esteem (
56). People have the self-confidence necessary for self-actualization when they feel appreciated. A variety of flexible reactions and adaptations are necessary for high self-confidence. Self-actualization can be improved when people’s problem-solving skills are tested (
57,
58). Those with rational thoughts and actions hold the belief that no one deserves blame or rejection for errors. They accept themselves and others unconditionally, regardless of their shortcomings or flaws. Individuals who think rationally can analyze their thought patterns, enabling them to handle their emotions more effectively and substitute anxiety-provoking thoughts with more reasonable and practical ones. These people are self-directed and take responsibility for their own emotions rather than blaming others for their problems (
38,
59,
60). This perspective allows individuals to improve their functioning and achieve greater self-actualization than others.
5.1. Conclusions
In conclusion, based on the findings of the present study, the Persian version of the SISA exhibits appropriate psychometric properties. This study can be regarded as a pioneering work in this sector because there are few thorough studies evaluating the psychometric characteristics of this questionnaire across different groups in Iran. It lays the groundwork for future research by highlighting the significance of self-actualization in individuals and opening the door for the creation of precise and useful measurement instruments in this area. Hence, applying the findings to different populations must be approached carefully. To enhance the generalization of the findings to various groups, it is recommended that future research investigates this tool across diverse demographics, including student and clinical populations. Another drawback of this study is that the data were gathered through self-report questionnaires. Self-report instruments frequently face two influencing factors: Social desirability and the inaccuracy inherent in self-reports.