To our knowledge, our study was the first attempt to validate the scales of ORTO in Chinese population. This study translated ORTO-15 and ORTO-R into Chinese and validated and compared the Chinese version scales among Chinese college students. Our findings suggested that the reliability of Chinese version of ORTO-15 and ORTO-R was acceptable. Previous related study showed various Cronbach’s α of ORTO-15 scale, ranging from 0.14 [23] to 0.82 [24]. Additionally, the Cronbach α coefficient of Arabic version ORTO-R was 0.78 and 0.76, respectively [25, 26]. The Greek version and Turkish version using the omega coefficient was 0.65 and 0.72, respectively [25, 27]. The Cronbach’s α were 0.79 and 0.77 of ORTO-15 and ORTO-R in the current study, similar to previous studies [12, 13, 28], which indicates that a satisfactory internal consistency of the instrument.
The exploratory factor analytic findings of this study produced a three-factor solution for ORTO-15, which consistent with the original version [5] and other studies [2, 9]. As for ORTO-R, the EFA yielded a two-factor structure in the Chinese version of ORTO-R. A one-dimentional measurement model of the ORTO-R fitting the data well were provided by Rogoza and Donini initially [25]. Subsequently, the Greek version of ORTO-R replicated successfully the findings proposed by Rogoza and Donini [25]. Furthermore, the ORTO-R in the Turkish language conducted by Yargic et al had a comparable result [27], whereas Hallit et al. [26] suggested that a two-factor solution in the Arabic version of ORTO-R.
We evaluated the rate of ON risk among college students by ORTO-15, which was 46.7%, whereas this prevalence ranged from 28.3% to 74.5% by other studies [13, 28, 29], which may be caused by the limitation of ORTO-15 test relating to distinguish whether the ON symptoms were pathological, thus leading to false positive results. Furthermore, the difference of the prevalence rate was owing to the sample characteristics [28]. For example, women, athletics and medical physicians were high-risk groups compared to the general population. Those people are usually attentive and cautious [30]. Undergraduates were at high risk likewise because body dissatisfaction and dieting for weight loss were prevalent among them [31].
Results from CFA of ORTO-15 and ORTO-R revealed that all the ORTO-15 models in our study failed to provide a good fit since the fit indexes (CFI, RMSEA and SRMR) apparently higher or lower than the criteria, indicating the Chinese version of ORTO-15 has an unstable factorial structure. Since the poor factorial structure in many different country studies, researchers had to remove some items to improve the stability of ORTO-15, therefore, the orthorexic thoughts and behaviours may not be fully evaluated. In addition, there were no generic version of ORTO-15 between different countries because each of the national versions retained different items. Thus, it seemed impossible to make cross-cultural comparisons [15]. On the other hand, these issues were expected to be addressed with the development of the promising ORTO-R tool. In our study, only the two-factor ORTO-R model had a satisfactory goodness-of-fit out of all models, which is similar to the factorial structure of Arabic version [26]. The ORTO-R also had an adequate internal reliability (α = 0.77, ICC = 0.82). As a result, the two-factor ORTO-R may be a more suitable tool to screen ON tendency for Chinese population. We also explored potential factors related with ON risk. Our findings showed that physical activities and mental disorders were related to ON risk assessed by both ORTO-15 and ORTO-R, suggesting that these two variables considerably might be the risk factors of ON.
Chinese people who engage in physical activities were more likely to have orthorexic tendency, which were in accordance with previous studies showing that sport activities played a significant role in ON [32]. Malmborg J et al. [33] compared the differences in the frequency of ON either in exercise science students or in business students, and concluded that exercise science students has a greater extent of ON than business students. Also, Clifford et al. [34] found that students undertaking ≥ 10 h per week of physical activity has lower scores than those ≤ 10 h per week. Under the circumstance that striving to reach the healthy nutrition, the motivation of frequent physical activities should be considered. Individuals do sports to improve health, but this can develop to exercise addiction with obsessive features such as calculating calories and guilt over skipping training [27].
We also found that people with depression, anxiety or ADHD were more likely to have the tendency of ON. This result was in agree with previous literatures, where participants scored lower in ORTO-15 reported that more participants were ever diagnosed with a psychiatric disorder [8, 35]. Our findings reinforced the evidence suggested the ON should be categorized into the scope of mental disease. However, He et al. [36] concluded that there was no association between ON and mental health impairment. The study was conducted among the elderly in East Asia using the instrument of Dusseldorf Orthorexia Scale (DOS). In their opinion, individuals with more ON symptoms had similar or less mental distress compared with those not [36]. The association of nature, strength, and provisionality between ON and mental illness should be validated with more studies [37].
In conclusion, the current study updated a new language version of ORTO questionnaires. We found a two-factor structure of the ORTO-R with an acceptable fit, indicated the Chinese version of ORTO-R might be reliable to assess ON risk in a China sample. Physical activities and mental disorders were the most likely contributing factors for ON risk. Further studies could be performed among various population and countries to confirm our results.
Strengths and limitations
To our knowledge, this is the first study to validate the scales of ORTO among Chinese college students. However, several limitations of the current study should be taken into consider. First, the data were obtained through self-report; hence, information bias might inevitable during the data collection. Second, the target population of this investigation was university students of China, so the results cannot be generalized to the whole population. Furthermore, as mentioned in the study conducted by Fernandez et al. [38], from a nutritional point of view, the youth is an especially vulnerable group and they will undergo a critical period for changing and establishing their lifestyle habits and food consumption during university. Moreover, subjects who voluntarily participate in this study may concerned more about dietary health, resulting in overestimated risk in the present study.
What is already known on this subject?
ORTO-15 is one of the most common instruments used for measuring orthorexic tendencies. Existing studies translated it from English to various languages and applied in many countries. However, several items of the ORTO-15 have been removed due to cultural differences between countries, there is no commonly version of ORTO-15 yet. Therefore, based on ORTO-15, the ORTO-R was developed as a new promising tool with the purpose of assessing orthorexic behavior better, whereas no study has validated the ORTO-R.
What this study adds?
To our knowledge, this is the first study to validate the scales of ORTO among Chinese college students. We found the Chinese versions of ORTO-R scale was reliable to assess ON among Chinese students, which was useful to make intensive studies of ON. The study also found physical activities and mental disorders were related with increased ON risk.