Introduction
The experience of chronic illnesses in children is distressing for children and their families. According to the definition provided by the National Center for Health Statistics (NCHS), a chronic illness is a disease that persists for at least three months or longer, cannot be prevented by vaccines or medication, and does not resolve spontaneously [1]. It is estimated that between 10% and 30% of children, depending on diagnostic criteria, suffer from chronic illnesses [2، 3]. A child with a chronic illness may experience multiple symptoms, including pain and fear; meanwhile, due to a lack of awareness of their bodily states, they may be unable to accurately express their pain and symptoms [4]. The importance of adult responses to children’s symptoms has led to the development of appropriate assessment tools, and multiple scales have been designed worldwide to evaluate parental responses to children’s symptoms. Accordingly, the first scale was the illness behavior encouragement scale (IBES), which assessed adult reactions to episodes of abdominal pain and other symptoms in children, with a specific focus on worry-related behaviors. This scale was later expanded into the social consequences of pain (SCP) questionnaire, which evaluated positive and negative responses from teachers, peers, and parents [12]. Finally, the IBES was modified and transformed into the adult responses to children’s symptoms (ARCS) questionnaire, a useful tool for assessment in this field, designed and developed in English by Van Slyke and Walker in 2006 [13].
The way adults respond to children’s needs varies significantly across societies due to cultural differences. Therefore, the lack of appropriate tools tailored to specific cultures highlights the need for a valid and up-to-date instrument. Hence, the present study validates and establishes normative data for the Persian version of the ARCS questionnaire in Iran. This study aims to answer the following research question: Does the ARCS questionnaire demonstrate acceptable validity for use among Iranian children with chronic illnesses?

Methods
This study employed a descriptive methodological research design, which falls under the category of quantitative research. The study population consisted of parents of children aged 4 to 16 years with chronic illnesses who were admitted to 17 Shahrivar Hospital in Rasht City, Iran, during the winter of 2021 and spring of 2022. A total of 290 parents were selected using a consecutive sampling method and voluntarily completed the ARCS questionnaire along with the child-parent relationship scale (CPRS) after providing written informed consent.
Sub-study 1: The objective of the first sub-study phase was to translate the ARCS questionnaire from English to Persian. The original English version of the ARCS questionnaire was independently translated by three translators with expertise in statistics and research methodology, health psychology, and pediatric diseases, using the TRAPD approach [15]. After reviewing each translation, the most comprehensible and accurate version was selected by four faculty members from the Department of Psychology at the University of Guilan, including the study researchers and dissertation supervisors.
Sub-study 2: The second sub-study phase assessed the test-retest reliability of the Persian version of the ARCS questionnaire. A total of 30 parents meeting the eligibility criteria were selected, and they completed the ARCS questionnaire twice, with a four-week interval between administrations.
Sub-study 3: The third sub-study phase focused on evaluating internal consistency reliability, construct validity (using confirmatory factor analysis), and criterion-related validity (by correlating ARCS scores with CPRS scores). To conduct confirmatory factor analysis (CFA) using the maximum likelihood (ML) method, an independent sample of 290 parents (separate from those in sub-study 2) was selected through consecutive sampling and based on the inclusion and exclusion criteria. The sample size was determined based on the presence of 58 path coefficients and error terms in the ARCS questionnaire.
In this study, the CPRS, originally developed by Pianta in 1994, was also used. This 33-item scale evaluates parents’ perceptions of their relationship with their child and comprises the following subdomains: conflict (17 items), closeness (10 items), dependency (6 items), and an overall positive relationship score (computed by summing the closeness score and the inverse of the conflict and dependency scores). The Cronbach α coefficients for these subdomains were reported as 0.84, 0.69, 0.46, and 0.80, respectively. Data analysis and validity assessment of the Persian ARCS questionnaire were performed using AMOS software, version 26 and SPSS software, version 26.

Results
This study included 290 parents of children aged 4 to 16 years with chronic illnesses in Rasht City, Iran, with a mean parental age of 38.19±6.92 years (mothers: 37.46±6.55 years; fathers: 40.83±7.46 years), ranging from 25 to 60 years. The mean age of the children was 9.04±3.78 years (girls: 8.84±3.46 years; boys: 9.21±4.03 years), ranging from 4 to 16 years.
To determine the construct validity of the ARCS, item-total correlations for the subscales were analyzed. The results indicated that each item demonstrated the highest correlation with its corresponding subscale. Accordingly, correlation coefficients ranged from 0.35 to 0.72 for supportive and monitoring behaviors, from 0.44 to 0.73 for protective responses, and from 0.53 to 0.66 for symptom minimization.
To assess concurrent criterion validity, the correlations between ARCS subscales and CPRS subscales were examined. The results revealed that supportive and monitoring behaviors had a negative correlation with conflict and a positive correlation with overall positive relationships, closeness, and dependency. Protective responses showed a positive correlation with closeness and dependency. Symptom minimization was positively correlated with conflict and negatively correlated with closeness and overall positive relationships.
Multiple linear regression analysis was conducted to determine concurrent criterion validity, with CPRS scores as the dependent variable. The regression results indicated that ARCS subscale scores significantly explained the variance in CPRS scores. Cohen describes R2 values of 0.26, 0.13, and 0.02 as strong, moderate, and weak, respectively [23]. The explanatory power of ARCS dimensions was 20% for conflict, 34% for closeness, 36% for dependency, and 19% for the overall positive relationship, indicating moderate to strong explanatory power.
Finally, normative tables were developed by converting raw scores into standardized Z and t scores and calculating percentile ranks for the 290 parents of children with chronic illnesses. For example, a Z-score of 0.84 for a supportive and monitoring behavior score of 26 indicates that the parent’s level of support and monitoring is higher than that of 75% of other parents.

Conclusion
The present study assessed the construct validity of the ARCS questionnaire by examining item-total correlations for subscales (n=290). The results indicated that each item was correctly categorized within its respective subscale. This analysis represents the first validation study of the ARCS questionnaire, and its findings are not directly comparable to previous research. Although the coping health inventory for parents (CHIP) questionnaire was translated and used in Iran, its validity and reliability, as well as item-total correlations for its subscales, were not reported [24]. According to the present findings, the Persian version of the ARCS questionnaire demonstrates satisfactory internal consistency and reliability, making it a suitable and valid tool for assessing parental responses to children’s symptoms in Iran. Given these results, the Persian ARCS questionnaire is a reliable instrument for use in research involving Iranian parents of children with chronic illnesses.

Ethical Considerations

Compliance with ethical guidelines
This study was approved by the Ethics Committee of the University of Guilan, Rasht, Iran (Code: IRGUILAN.REC.1400.046).

Funding
This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors.

Authors' contributions
Conceptualization, study design, supervision, review and editing: Sajjad Rezaei and Azra Zavared; Data acquisition, analysis, and interpretation: Yasman Larijani and Sajjad Rezaei; Writing the original draft: Yasman Larijani and Azra Zavared; Statistical analysis: Yasman Larijani; Administrative, technical, or material support: Shohreh Maleknejad and Bahram Darbandi.

Conflicts of interest
The authors declared no conflict of interest.

Acknowledgements
The authors would like to thank the Vice Chancellor for Research of Guilan University of Medical Sciences, the officials and staff of 17 Shahrivar Hospital in Rasht, and all participants in this study.