This cross-sectional study was conducted at ……………………………. in 2018. The sample was randomly selected from the population of students of ………………………. After receiving the goals and accepting the informed consent form, all participants in this study (n=665) were entered into the study. All the scientific and executive stages of this study have been approved by the Ethics Committee (registry number: ………….REC.1397.314). The completion of at least one year of university education was the main criterion for inclusion in this study. Students with previous history of neck injury or disorder (as a self - reported question), were excluded from the study. The following questionnaires were used for data collection. Demographic information was also collected.
2.1. Virtual Social Network Addiction Questionnaire:
This tool contains 43 questions that were rated as five-point Likert (never, almost never, sometimes, often and always). Seven dimensions of addiction to virtual social networking are measured in this questionnaire. These dimensions include loss of control, academic failure, dependency, avoidance syndrome, mood changes, reduced interest in other activities and social conflicts. The minimum and maximum attainable scores for each student were 43 and 215, respectively. To answer the main questions of the study, only the total score of the questionnaire, which represents the total score of social network addiction, was used. The validity and reliability of this questionnaire were approved in the Lindsay et al. study[29]. This tool also used in ……… students after the acquisition of an acceptable level of reliability and validity in the same culture study[30].
2.2. Problematic online Game Questionnaire:
Another tool to collect the required data was the problematic online game questionnaire[31]. The instrument has 18 questions to be answered by the participants in the five - point Likert (never, rarely, sometimes, often, and always). This tool has six sub-scales, including social isolation, interpersonal conflicts, excessive use, neglect, immersion and fascination. In order to measure addiction to online games, only the final scores achieved were used in the statistical analysis. The validity and reliability of this questionnaire have been confirmed by Kuss DJ et.al[32]. Aminimanesh et al. [33] have validated this instrument in accordance with ……… Culture.
2.3. Nordic musculoskeletal questionnaire:
Data on neck musculoskeletal disorders were collected by Nordic questionnaire [34]. Participants answered questions on neck disorder in three periods, in general, in the past month and the day before. Their responses were based on a body diagram.
In this study, descriptive results were reported in terms of mean, percentage and standard deviation. Participants' data were compared using Chi-square, T-test and then simple and multiple logistic regression were presented. The surface under the receiver operating characteristic (ROC) curve was used to compare the importance of independent variables in prediction neck pain. Discriminant analysis was utilized to propose a function to classify people who were not involved in the analysis into one of the two groups - with and without neck pain-. The level of confidence in presenting results was 95 percent. The SPSS version 16 and STATA version 11 software packages were used for data analysis.