Introduction
amily-centered services are the collection of values, attitudes, and approaches to services for children with special needs and their family, in which families are considered as an expert about children’s needs [1]. Family-based philosophy is used in a wide range of specialties, such as health care (medicine, nursing, etc.), early intervention, rehabilitation team, early childhood education, and general and private education [2]. Improving the quality of family-centered services, given their importance in various stages of treatment, is essential, which requires the existence of a tool to measure its strengths and weaknesses. Several tools are available for measuring these services from the perspective of parents and service providers, including Family-Focused Intervention Scale (FEIS), Family-Provider Intervention Analysis, Family Orientation of Community and Agency Service (FOCAS), and Measure of Process of Care- Service Provider (MPOC-SP) [3, 4]. MPOC-20 can also be used to overcome the limitations of earlier tools in measuring parental perspective and usability in children and adolescents of all ages and with a variety of chronic physical and mental illnesses [2]. The first version of this questionnaire comprised 56 items with five domains. In 2004, the questionnaire was shortened and summarized to 20 items [4].
The tool has been studied in several countries for its validity and reliability, including in the Netherlands [5], Norway [6], Japan [7], Korea [8], Brazil [9], Jordan [10], Slovenia [11], and Malaysia [12]. In addition, the validity and reliability of this instrument have been specifically performed on a group of diseases, such as cancer and epilepsy [13, 14]. In most studies, Cronbach’s alpha was above 0.6 and the questionnaire showed good reliability. In a study conducted in 2016 to examine the demographic characteristics of the test among people with epilepsy, MPOC-16 reflected family-centered care in these patients And was easier to evaluate and interpret compared with other scales [14]. 
This questionnaire has been used in many studies to examine family-centered services from the perspective of family and service providers [15, 16, 17, 18]. For example, the MPOC-20 questionnaire was used by Jeglinsky et al. in Finland in 2012 to assess parents ‘views and the MPOC-SP questionnaire was used to examine therapists’ viewpoints [16]. In this study, the “Supportive and Respective Care” item showed the highest score, and the “Providing General Information” item showed the lowest score.
Today, the importance of family-center services and their key role in treatment processes, and the irreplaceable impact of the family during the treatment process is clear. Given the importance of the MPOC-20 tool in evaluating and promoting family-centered services, as well as the growing importance of these services in Iran, Qashqai et al. translated this tool in 2011 to Persian [19]. In order to apply this tool to evaluate family-centered services in other studies, we examined its content and structure validity and reliability.
Materials and Methods
Participants
The present study cross-sectional psychometric study was done to validate the MPOC-20 instrument in 2018. The convenience sampling method was used on parents referring to various rehabilitation centers in Tehran. Rehabilitation centers were also selected through available sampling. The study population consisted of 340 parents of children with developmental disabilities (with various diseases, including cerebral palsy, learning disorder, autism, etc.) who had received rehabilitation services for at least three sessions. In this study, children with disabilities aged 0-18 years were examined and children with cerebral palsy had the highest percentage (28.8%) among patients. Also, 142 patients were girls (42%) and 198 boys (58%) who were randomly selected from public and private rehabilitation centers in different parts of Tehran and among the responding parents, most of the subjects were female (92.4%).
Instrument
MPOC-20
The first version of the MPOC has 56 items and was developed in 1996 by Susan King et al. to evaluate family-centered services with five domains: 
1. Enabling and partnership; 2. Providing general information; 3. Providing specific information about the child; 4. Coordinated and comprehensive care for the child and family; and 5. Respectful and supportive care [20, 21].
In 2004, the questionnaire was shortened to 20 items [4]. Its domains are divided into the following five domains: items 4, 7, and 8: enabling and participation domain, items 16 to 20: public information domains, and items 2, 14, and 15: specific information domains. Items 5, 6, 10, and 12 are in the domain of comprehensive and coordinated care for the family and the child, and items 1, 3, 9, 11, and 13 are related to the supportive and respectful care domain [6].
Materials and Methods
The present study was conducted in 2018 in rehabilitation centers in Tehran. First, the main questionnaire and its Persian version were taken from the original author of the questionnaire, and to check the content validity, the Persian questionnaire was given to 14 occupational therapy professors who had at least three years of experience in working with children. The obtained data were analyzed, and the Content Validity Ratio (CVR) and Content Validity Index (CVI) values were calculated. Then, the obtained values were reviewed in a meeting with experts, and the necessary corrections were made to the questionnaire. These corrections included minor changes to the text of some questions, which were changed to better understand the meaning of the sentence. Then, the consent form and demographic information (including age and sex of the child, duration/number of sessions referring to the occupational therapy clinic, and type of respondent parent) were provided to 340 parents referring to rehabilitation centers, and they answered the questions. The obtained data were analyzed for validity and reliability. Then, in order to determine the reliability of the test-retest, two weeks after completing the questionnaire, 30 participants were asked to complete the questionnaire again.
Data analysis 
To assess the content validity, the occupational therapist’s comments about the necessity (CVR), simplicity, clarity, and relevance were evaluated and the values of CVR and CVI were calculated. The acceptable value for each question varies according to the number of experts who determine the CVR. According to the Laosche method, the least acceptable value is 0.51 for 14 people [22]. As a result, the question is acceptable if the CVR is between 0 and 0.51 and the numerical mean of judgments is equal to or higher than 5/1. This indicates that more than half of the panel members selected the required item. After collecting data from parents, the Spearman correlation coefficient and Cronbach’s alpha coefficient were calculated to examine the internal consistency between the data. If the coefficient is more than 0.8, the consistency in the questionnaire has a very good level. Values ​​of 0.7 to 0.79 indicate a moderate level and values ​​below 0.7 indicate an undesirable level of consistency. To determine the reliability of the test-retest, the value of the Interclass Correlation Coefficient (ICC) was calculated. The ICC values ​​of 0.8 or higher indicate very good reliability, values between 0.6 and 0.79 indicate moderate reliability, and values less than 0.6 represent poor reliability. Then, the Standard Error of Measurement (SEM) was determined. The SEM value of less than 0.01 of the maximum score obtained in that area indicates good reliability of the tool. Data were analyzed using SPSS V. 20 software.
Results
In this study, the responses of 340 parents of children with disabilities with different diagnoses were analyzed. Table 1 shows the demographic characteristics of parents and children in the test and retest phase.


The results of the first stage of validity, where a questionnaire was given to 14 professors of occupational therapy to determine the content validity, are summarized in Table 2.


Regarding the content validity index, the collected data are presented in Table 3.


To investigate the internal consistency of items, the correlation between different domains of the questionnaire and also its Cronbach’s alpha value were calculated. The correlation coefficient and Cronbach’s alpha for each domain are presented in Table 4.


Also, the p-value was significant for all domains at 0.001 level.
To evaluate the reliability of the instrument over time, two consecutive measurements (with a two-week interval) were performed. Reliability of the supportive care domain showed a high coefficient and good reliability and other domains showed average reliability. The overall ICC value was 0.9. As shown in Table 5, all SEM values are lower than the score obtained in the scores of the studied domains, which indicates the acceptable reliability of the questionnaire.


Discussion and Conclusion
The quality of family-centered services should be increased by more investigations using appropriate tools, such as MPOC-20 as an accepted measurement tool. Therefore, the present study was conducted to evaluate the validity and reliability of the Persian version of the MPOC-20 questionnaire.
The obtained CVR value showed that the lowest score was related to question 6 of the questionnaire. This question is related to the stability of at least one member of the treatment team in providing services, which some professors did not consider necessary for family-based services in Iran and stated that it is not possible to implement it in government and educational centers in Iran. In examining the value of CVI, the average value was obtained for 17 questions of the questionnaire was acceptable and higher than 0.79. Considering viewpoints and suggestions of the expert panel and also consultation with the original author of the questionnaire, questions 1, 3, and 12 did not obtain the acceptable score due to lack of clarity, and then changes were made to the text of some of these questions to clarify and increase their clarity. These changes included changing the word “competency” to “capability” in question 1, explaining the “organization reference library” in question 20, simplifying the sentence in question 3, and using “providing a supportive environment instead of “Just give you information”, and also “In addition to providing information, do they provide a supportive environment?”
In this study, Cronbach’s alpha was used to evaluate the internal consistency of the questionnaire items. The Cronbach’s alpha was found to be 0.801, which indicates that the MPOC-20 questionnaire has an acceptable internal correlation. The lowest Cronbach’s alpha was related to “Enabling and Partnership” and the highest was related to “Providing General Information”, which may be due to the low level of parent’s educational level or the lack of client-centered treatment process in some clinics. The results of this part of the study are aligned with the findings of a study conducted by Antuneus et al. (2020) in Brazil, in which the total Cronbach’s alpha was 0.61-0.91. The lowest Cronbach’s alpha was related to “Enabling” (α = 0.61) and the highest was related to “Providing general information” (α = 0.91) [12]. In a study conducted in Norway, the lowest Cronbach’s alpha was related to “Providing specific information about the child” [6]. In another similar study conducted by Siebes et al. in 2007, they examined the internal consistency of the questionnaire on 405 mothers and 22 fathers of children aged 0-18 years with different diseases. They reported the Cronbach’s alpha of 0.75 - 0.87, indicating acceptable reliability of the instrument in the Netherlands [5]. The correlation coefficient was also used in other studies in Jordan and Malaysia and in both studies, the Cronbach’s alpha was obtained above 0.75, which is consistent with the results of the present study [10, 23].
Regarding the test-retest reliability in this study, the ICC of the total score was 0.9, which indicates the high reliability of this questionnaire. Also, the lowest value of ICC was related to the domain “Providing general information” (0.8) and the highest value is related to the domain “Respectful and Supportive Care”(0.9). In a similar study conducted in Norway in 2012, the test-retest reliability of the questionnaire was examined at intervals of 2-6 weeks and the overall ICC value was 0.78-0.86. Also, the highest level of ICC was related to the domain of ​​“Respectful and Supportive Care”, which is consistent with the findings of the present study [6]. In another similar study conducted in 2018 in Korea, the ICC for the whole scale was above 0.8(8), which represents the acceptable reliability of the questionnaire and is in line with the results of the present study. The coherence of the results means that the questionnaire has acceptable measurement accuracy, stability, and reliability over time.
Considering the compatibility of the Persian version of the questionnaire with the English version, its adaptation to the cultural and contextual characteristics of Iranian society, and also the number of acceptable samples studied in this study, it could be stated that the Persian version of the MPOC-20 questionnaire can be used as a practical and useful tool to evaluate family-centered services provided to children with various disabilities. Because this study was performed among children with various developmental disabilities, it is suggested the validity and reliability of this tool be investigated on certain groups of patients in future studies.

Ethical Considerations
Compliance with ethical guidelines
This study was approved by the Ethics Committee of the Shahid Beheshti University of Tehran( Code: IR.SBMU.RETECH.REC.1399.479). All ethical principles are considered in this article. The participants were informed of the purpose of the research and its implementation stages. They were also assured about the confidentiality of their information and were free to leave the study whenever they wished.

Funding
This article was extracted from the MSc. thesis of the first author at the Department of Occupational Therapy, Faculty of Rehabilitation Sciences, Shahid Beheshti University of Tehran.

Authors' contributions
Conceptualization, methodology: Mehdi Rezaee, Zahra Pashazadeh, Reyhaneh Kaviani, Mehdi Tabatabaee. Investigation, resources: Reyhaneh Kaviani; Writing – original draft preparation, writing – review & editing: Reyhaneh Kaviani, Hossein Gerivani. 

Conflict of interest
The authors declared no conflict of interest.
 

References

1. Dunst CJ. Family-centered practices. The Journal of Special Education. 2002; 36(3):141-9. [DOI:10.1177/00224669020360030401]
2. Dalvand H, Rassafiani M, Bagheri H. Family centered approach: A literature review. Modern Rehabilitation. 2014; 8(1):1-9. https://web.b.ebscohost.com/abstract?
3. Dempsey I, Keen D. A review of processes and outcomes in family-centered services for children with a disability. Topics in Early Childhood Special Education. 2008; 28(1):42-52. [DOI:10.1177/0271121408316699]
4. King S, King G, Rosenbaum P. Evaluating health service delivery to children with chronic conditions and their families: Development of a refined Measure of Processes of Care (MPOC− 20). Children’s Health Care. 2004; 33(1):35-57. [DOI:10.1207/s15326888chc3301_3]
5. Fauzi NF, Ern MA, Rasdi HF, Saat NZ. The Measure of Processes of Care 20-Item (MPOC-20): Validity and reliability of the malay version. Jurnal Sains Kesihatan Malaysia (Malaysian Journal of Health Sciences). 2015; 13(2):61-7. [DOI:10.17576/jskm-2015-13(2)7]
6. Siebes RC, Maassen GH, Wijnroks L, Ketelaar M, van Schie PE, Gorter JW, et al. Quality of paediatric rehabilitation from the parent perspective: Validation of the short Measure of Processes of Care (MPOC-20) in the Netherlands. Clinical Rehabilitation. 2007; 21(1):62-72. [DOI:10.1177/0269215506071280] [PMID]
7. Hagen AK, Bjorbækmo W. Parents evaluation of the processes of care in child rehabilitation: A reliability study of the Norwegian translation of MPOC-20. Child: Care, Health and Development. 2012; 38(1):48-53. [DOI:10.1111/j.1365-2214.2010.01192.x] [PMID]
8. Himuro N, Kozuka N, Mori M. Measurement of family-centred care: translation, adaptation and validation of the Measure of Processes of Care (MPOC-56 and-20) for use in Japan. Child: Care, Health and Development. 2013; 39(3):358-65. [DOI:10.1111/j.1365-2214.2012.01371.x] [PMID]
9. Saleh M, Almasri N. Use of the Measure of Processes of Care (MPOC-20) to evaluate health service delivery for children with cerebral palsy and their families in Jordan: validation of Arabic-translated version (AR-MPOC-20). Child: Care, Health and Development. 2014; 40(5):680-8. [DOI:10.1111/cch.12116] [PMID]
10. An M, Kim J, Kim J. Measure of Processes of Care (MPOC): Translation and validation for use in Korea. Child: Care, Health and Development. 2018; 44(4):545-51. [DOI:10.1111/cch.12577] [PMID]
11. Groleger Sršen K, Vidmar G, Zupan A. Validity, internal consistency reliability and one-year stability of the Slovene translation of the Measure of Processes of Care (20-item version). Child: Care, Health and Development. 2015; 41(4):569-80. [DOI:10.1111/cch.12198] [PMID]
12. Antunes AAM, Furtado SRC, de Castro Magalhães L, Kirkwood RN, Vaz DV. Brazilian versions of the Measure of Processes of Care-20 and Measure of Processes of Care-Service Providers: translation, cross-cultural adaptation and reliability. Brazilian Journal of Physical Therapy. 2020; 24(2):144-51. [DOI:10.1016/j.bjpt.2019.02.013] [PMID] [PMCID]
13. Klassen A, Dix D, Cano S, Papsdorf M, Sung L, Klaassen R. Evaluating family-centred service in paediatric oncology with the Measure of Processes of Care (MPOC-20). Child: Care, Health and Development. 2009; 35(1):16-22. [DOI:10.1111/j.1365-2214.2008.00887.x] [PMID]
14. Joachim KC, Wilk P, Ryan BL, Speechley KN. Family-centered care in children with epilepsy: Evaluating the Measure of Processes of Care (MPOC-20). Epilepsia. 2016; 57(10):1660-8. [DOI:10.1111/epi.13494] [PMID]
15. Siebes RC, Wijnroks L, Ketelaar M, Van Schie PE, Vermeer A, Gorter JW. One-year stability of the Measure of Processes of Care. Child: Care, Health and Development. 2007; 33(5):604-10. [DOI:10.1111/j.1365-2214.2007.00726.x] [PMID]
16. Bellin MH, Osteen P, Heffernan C, Levy JM, Snyder-Vogel ME. Parent and health care professional perspectives on family-centered care for children with special health care needs: Are we on the same page? Health & Social Work. 2011; 36(4):281-90. [DOI:10.1093/hsw/36.4.281] [PMID]
17. Jeglinsky I, Autti-Rämö I, Brogren Carlberg E. Two sides of the mirror: Parents’ and service providers’ view on the family-centredness of care for children with cerebral palsy. Child: Care, Health and Development. 2012; 38(1):79-86. [DOI:10.1111/j.1365-2214.2011.01305.x] [PMID]
18. Schenker R, Parush S, Rosenbaum P, Rigbi A, Yochman A. Is a family-centred initiative a family-centred service? A case of a Conductive Education setting for children with cerebral palsy. Child: Care, Health and Development. 2016; 42(6):909-17. [DOI:10.1111/cch.12354] [PMID]
19. Almasri NA, An M, Palisano RJ. Parents’ perception of receiving family-centered care for their children with physical disabilities: A meta-analysis. Physical & Occupational Therapy in Pediatrics. 2018; 38(4):427-43. [DOI:10.1080/01942638.2017.1337664] [PMID]
20. Bertule D, Vetra A. Predictors of needs for community and financial resources for families of pre-school children with cerebral palsy. SHS Web of Conferences: 5^th International Interdisciplinary Scientific Conference Society Health Welfare. 2016; (30):10. [DOI:10.1051/shsconf/20163000041]
21. Fontil L, Petrakos HH. Transition to school: the experiences of canadian and immigrant families of children with autism spectrum disorders. Psychology in the Schools. 2015; 52(8):773-88. [DOI:10.1002/pits.21859]
22. Sidney C, Reynolds F. Occupational therapy for children with Attention Deficit Hyperactivity Disorder (ADHD), part 2: A multicentre evaluation of an assessment and treatment package. British Journal of Occupational Therapy. 2007; 70(10):439-48. [DOI:10.1177/030802260707001005]
23. Ghashghaei M. [Face validity of Measure of the Process Of Care-20 (Persian)]. [MA. thesis]. Tehran: University of Social Welfare and Rehabilitation Sciences; 2011.
24. King SM, Rosenbaum PL, King GA. Parents ‘perceptions of caregiving: development and validation of a measure of processes. Developmental Medicine & Child Neurology. 1996; 38(9):757-72. [DOI:10.1111/j.1469-8749.1996.tb15110.x] [PMID]
25. Lammi BM, Law M. The effects of family-centred functional therapy on the occupational performance of children with cerebral palsy. Canadian Journal of Occupational Therapy. 2003; 70(5):285-97. [DOI:10.1177/000841740307000505] [PMID]
26. Hassanzadeh Rangi N, Elahyari T, Khosravi Y, Zaeri F, Sameri M. [Designing a job cognitive failure questionnaire: Determining the reliability and reliability of the tool (Persian)]. Health Work of Iran. 2013; 9(1):29-40. http://ioh.iums.ac.ir/article-1-708-fa.html