Design and Evaluation of Measurement Tool for Sitting Situation Using Validity and Reliability

The sitting posture and its related problems are of high importance. The current research was conducted with the aim of design and evaluation of a measurement tool for sitting situation, using validity and reliability.
Instruments and In this semi-experimental (field trial) study, a number of questions about knowledge, attitude, and behavior were designed and content validity and face validity were utilized to assess the validity. Then, questionnaire was given to 10 specialists in health education, physiotherapists, and ergonomists. Moreover, Content Validity Ratio (CVR) and Content Validity Index (CVI) were calculated to determine content validity, and for reliability assessment, two criteria were used, including internal consistency through Cronbach's alpha and test-retest through Intra-class Correlation Coefficient (ICC) and Pearson correlation coefficient. Consequently, 30 students were enrolled in the study. The data were analyzed by SPSS 22 software.
Findings: Firstly, of all 29 questions in terms of knowledge, attitude, and behavior, 23 items remained with CVR higher than 0.6 and CVI tables were higher than 0.7. From 23 items referring to the 3 mentioned spectra, 12 questions were in the field of knowledge, 6 questions were in the field of attitude, and 5 questions were in the field of behavior. Then, the Cronbach's alpha coefficient was 0.87, the ICC was 0.983, and Pearson correlation coefficient was 0.966 (p<0.001). The designed questionnaire can appropriately examine sitting situation in terms of the knowledge, attitude, and behavior; therefore, it is an excellent tool for measuring these characteristics owing to satisfactory validity and reliability.