Extended Abstract
Introduction
Multiple Sclerosis (MS) is a disease related to the immune system and affects about 2.5 million people worldwide. This disease can cause problems such as fatigue, sensory impairment, motor system disorders, bladder and bowel dysfunction, cognitive impairment, and depression [1]. MS and its disabilities lead to functional limitations and greatly affect people’s daily lives and their ability to participate effectively in the family and society [2-4].
The International Classification of Functioning, Disability, and Health defines participation as a person’s involvement in a variety of life situations [5]. Participation in purposeful activities promotes self-confidence and skills and leads to physical, mental, and emotional health [6, 7]. Studies of people with MS show that they experience problems in different areas of participation and activity [8, 9].
Attention to the environment as a factor influencing performance has its roots in the history of science. In The Origin of Species, Darwin proposed that the behavior of living organisms is formed based on the environment in which they live [10]. Since then, researchers in various fields have sought to understand the concepts of environment and health and the relationship between them. Ecological theories later emphasized the effects of the environment on participation and suggested the need to change environmental factors instead of focusing solely on changing people’s behavior [11]. Recent models of human performance emphasize the environment as a determining factor in the development of disability and agree that disability cannot be understood without considering the environment [12]. Physical, social, and attitude environment can create serious limitations on the level of participation of people with MS [5]. 
Lexell et al. mentioned the lack of appropriate social support as the most essential factor in limiting the participation of people with MS [13]. In Ephraim and Law studies, the natural and man-made environment have been regarded as the most crucial environmental barriers [14, 15]. Liao et al. study showed that the design of the physical environment and buildings and services creates the gravest limitations for stroke patients [16]. Environmental barriers can also be one of the reasons for the limited mobility of disabled people, which in turn leads to their social isolation, difficulty in performing daily activities, not participating in leisure activities, lack of proper use of health care services, and the like [17-21].
Given that the prevalence of MS in Isfahan is high [22, 23], it is necessary to consider the participation of these people in various personal and social activities. We should identify environmental barriers for their participation and remove them to maintain the independence of these people and increase their quality of life [24]. Using the Craig hospital environmental factors questionnaire, we studied the environmental barriers affecting the participation of people with MS.
Materials and Methods
The statistical population of the present study consisted of all patients with MS who referred to MS Clinic of Kashani Hospital in Isfahan City, Iran. The sample size for analysis of variance by GPOWER software was estimated as 66 people taking into account the effect size of 0.4, the type I error of 0.05, and the test power of 0.8. Also, the required sample size was estimated to be 84.5 people, taking into account the r value of 0.3, the type I error of 0.05, and the test power of 0.8.
Then, considering the probability of dropout, the sample size was considered to be 100 people. Finally, 96 MS patients were selected by the convenience sampling method. The criteria for admission were 1. diagnosis of MS by a neurologist; 2. age between 25-55 years; 3. living in Isfahan for at least the past year; 4. not having severe cognitive impairment; 5. consent of the patient to participate in the research.
After informing the participants about the purpose of the research and obtaining their consent, they were assured of the information confidentiality and their demographic information was completed. For each individual, the Mini-Mental State Examination (MMSE) questionnaire was completed and then the scores on the Expanded Disability Status Scale (EDSS) were recorded by a neurologist. Finally, the Craig Hospital Inventory of Environmental Factors (CHIEF) was provided to the participants to fill it out.
The MMSE test examines orientation, recording information, attention, calculation, recalling, and language skills. The maximum score for this test is 30. A score between 21 and 26 indicates mild cognitive impairment; a score of 11 to 20 indicates moderate cognitive impairment, and a score of 10 or lower indicates severe cognitive impairment. Using the simultaneous criterion method, the validity of this test was found good. Also, the test reliability was found 78%  based on the calculation of the Cronbach α. Foroughan et al. have standardized this test in Iran [25].
The EDSS score is a criterion for determining the level of disability of patients with MS and is graded based on the level of neurological damage from 0 (normal neurological status) to 10 (death due to MS) [26].
CHIEF measures the environmental factors that limit participation. Its Cronbach α was reported as 0.93 and its ICC coefficient 0.93 [7]. The validity and reliability of this questionnaire in Iran were examined by Nobakht et al. and reported its Cronbach α coefficient was found 0.86 and the ICC coefficient for all subscales was more than 0.7 [27].
The obtained data were analyzed in SPSS version 16. The mean and standard deviation indicators were used to describe the data. The Shapiro-Wilk test was used to evaluate the normality of data distribution, and the Pearson correlation coefficient statistical test and variance analysis test and post hoc test by LSD‌ method at 0.05 level were used to analyze the data. Also, considering that the variance analysis test is sensitive to variance heterogeneity, the Levene’s test was first performed to evaluate the homogeneity of variances.
Results
Participants in this study included 96 patients with MS, (22.9% male, and 77.1% female). Also, the education of the majority of participants (40.6%) was at the diploma level. Table 1 lists other demographic information including age, duration of illness, EDSS score, and MMSE score.
Table 2 reports the rate of encountering environmental barriers in different areas of participation according to descriptive statistics. The results show that the highest obtained average (12.05) is related to the subscale of physical and structural barriers and the lowest average (2.24) belonged to the work and school subscale. The percentage of encountering environmental barriers is also mentioned in this Table. In addition to the overall percentage of encountering environmental barriers, the percentage of encountering environmental barriers to scores of 3 or higher (indicating significant, continuous, and effective exposure to environmental barriers) is also mentioned in this Table similar to Ephraim et al. study [14].
Before the statistical analysis, the normality of the data distribution was assessed by skewness and kurtosis, followed by the Shapiro-Wilk test. The results showed that the data distribution was normal (P>0.05). The Pearson correlation test was used to investigate the relationship between the rate of encountering environmental barriers to participation in different areas, age, duration of disease, EDSS, and MMSE scores (Table 3). No significant relationship was found between the encountering environmental barriers to participation with these variables (P>0.05). To compare the average rate of encountering environmental barriers to participation in terms of education, Levene’s test was performed first. As it confirmed the assumption of homogeneity of variances for the rate of encountering environmental barriers to participation in different areas in terms of education (P>0.05), the Analysis of Variance (ANOVA) test was used. 
Table 4 shows a comparison of the average rate of encountering environmental barriers to participation in different areas (policies, physical and structural, work and education, attitudes and support and services and assistance) in terms of education along with variance analysis results. It was observed that the average rate of encountering environmental barriers to participation in the field of services and assistance is significantly different between various levels of education. The highest average is related to the lower secondary education (or below) group, and the lowest average to the bachelor’s degree (or above) group. 
There is no significant difference in other areas. To compare the average difference between the rate of encountering environmental barriers to participation in the field of services and assistance in terms of education, the post hoc test using the LSD method was used. The average difference in the rate of encountering environmental barriers to participation in the field of services and assistance is significant between the lower secondary education (or below) group and the bachelor’s degree (or above) group, as well as between the diploma and bachelor’s degree (or above) groups.
To compare the average rate of encountering environmental barriers to participation in different areas (policies, physical and structural, work and education, attitudes and support and services and assistance) in terms of gender, we first performed the Levene’s test to assess the consistency of variances. As the results of the test (P>0.05) confirmed the similarity of variances for the rate of encountering environmental barriers to participation in different areas in terms of gender, the ANOVA test was used. Table 5 compares the average rate of encountering environmental barriers to participation in different areas in terms of gender. Based on the ANOVA test results, no significant difference between the averages in terms of gender was observed (P>0.05).
Discussion
MS affects participation in personal and social activities, and environmental barriers are among the most important factors that can aggravate this limitation. In this study, the highest reported environmental barriers were physical and structural and the lowest ones were the work and school. These results were consistent with the findings of the Ephraim et al. study [14]. Also, Hamed stated that the biggest environmental barriers against MS patients are the physical and structural barriers [28]. Using the IPA questionnaire, Cardol et al. in a study of 18- to 75-year-old people in five different disability groups reported the greatest limitations in the areas of work and education [29]. These results are not in line with our results. In addition to the difference in the questionnaire, the minimum age of the subjects studied (25 years), and the low level of their education was also significant. Also, Whiteneck and Ephraim stated that the work and school subscale in the Craig questionnaire measures environmental barriers in people who are studying or working but does not measure barriers to employment or education [14, 30]. 
In terms of attitudes and support, the highest score was related to the attitudes at home. Hamed also stated that one of the most crucial environmental barriers is the attitude of first-degree family members and relatives. This finding is significant because of the family-centered culture of countries such as Iran and Jordan [28]. In general, working conditions and attitudes have been suggested as the most important causes of job loss in these patients [31].
 Gray et al. introduced physical barriers and attitudes as environmental factors affecting the lives of people with various disabilities, including MS [32]. Khan and Lexell, in their studies on people with MS, also identified attitudes and social support as the most essential environmental factors (13.5). Also, the results of Keysor et al. study showed that in the long run, the most crucial factor that limits patients’ participation in activities is the lack of appropriate social support [33].
Our study showed that demographic variables were unrelated to the rate of encountering environmental barriers to participation. This finding is consistent with the results of Badia et al. study. They stated that disability characteristics (such as the level of disability) did not affect patients’ participation in leisure activities, but environmental barriers limit participation in activities [34]. The results of the Yorkston et al. study show that in many areas, the rate of participation of people with MS has nothing to do with the severity of their disability. But if the patient’s disability increases, his or her sense of confidence and self-efficacy to participate in activities will reduce, and the patient despite having a sense of self-efficacy may not be able to perform the activity due to environmental barriers [35].
The results of the present study concerning demographic variables are not consistent with the results of Ephraim et al. study. Hamed study also shows that demographic variables (age, level of education, duration of illness) are related to MS patients’ rate of encountering environmental barriers [28]. Ephraim et al. stated that amputated patients over the age of 55 had a lower rate of encountering environmental barriers than younger patients due to the greater ability of older people to adapt to their disability or because of lower participation in activities [14]. On the other hand, Hamed stated that in older MS patients, the rate of encountering environmental barriers increases due to the long duration of the disease and exacerbation of physical and cognitive problems [28]. 
The age range of the participants in Ephraim study was 18 to 84 years, so in the present study to reduce the effects of aging on the results of the study, the age range of 25 to 55 years was considered and this factor could be the reason for the difference in results. Hamed study did not specify the age range of the participants, but given that the average age of those participants and the participants in the present study was almost the same, a different measurement method (using a researcher-made questionnaire) could be the reason for the difference in results. 
Also, the results of the present study indicate that gender is not a factor affecting the rate of encountering environmental barriers, which is consistent with the results of the Hamed study [28]. These results are inconsistent with the results of the Ephraim study. He stated that the rate of encountering environmental barriers in the field of physical and structural barriers is lower in women than men. He argued that women do not have high expectations of themselves for doing physical activities [14]. Miller and Dishon argued that women with MS experience more limitations in physical and emotional functioning [36]. 
Another result of the present study was that the rate of encountering environmental barriers in the field of services and assistance was significantly different in people with different levels of education so that people with a bachelor’s degree or higher were less likely to face environmental barriers in this area. Although there are no specific studies on this subject, studies have been conducted on the level of education and employment of MS patients. Honarmand found that lower education did not result in higher unemployment among MS patients [37]. In contrast, Julian et al. found that people with higher levels of education were less likely to lose their jobs [38]. 
It seems that having a higher level of education makes a person more aware of his/her illness and improves his or her ability to cope with the challenges and limitations of the disease and can improve the level of participation of the patients [39, 40]. According to epidemiological studies, Isfahan is one of the areas with medium to high risk of MS in the world, so it is important to pay attention to the participation of these people in society [41, 42].
Conclusion
People with MS encounter a high rate of environmental barriers, especially in the area of physical and structural barriers. These barriers can limit their participation in personal and social activities.
Because of the high prevalence of MS in Iran and the high rate of exposure of these patients to environmental barriers, it seems necessary to eliminate environmental barriers and provide these patients the possibility of participating in individual and social activities, which can improve their wellbeing and quality of life. It is suggested that in future studies, the rate of encountering environmental barriers be evaluated based on different types of multiple sclerosis. In the field of clinical work, it is also suggested that specialists and therapists, besides considering the limitations of performance and body shape, examine the evaluation and intervention of environmental barriers.
Ethical Considerations
Compliance with ethical guidelines
This study ethically approved in Ethics Committee of Isfahan University of Medical Sciences (Code: IR.MUI.REC.1394.2.074)
Funding
The present article is the result of an approved research project at Isfahan University of Medical Sciences (Code number: 294074). 
Authors' contributions
Conceptualization, supervision: Nasrin Jalili; Methodology: Nasrin Jalili, Ehsan Jamshidian; Investigation, project administration: Nasrin Jalili, Ehsan Jamshidian, Ali Pour Safa; Writing-review & editing, visualization, funding acquisition: All authors.
Conflicts of interest
The authors declared no conflict of interest.

Acknowledgements
The authors of the article would like to express their gratitude to the Center for Musculoskeletal Research of the Faculty of Rehabilitation of Isfahan University of Medical Sciences, who financially supported this research.