Developing knowledge level scale of functional foods: Validity and reliability study
The aim of the study was to develop a scale to determine the knowledge levels of University students on functional foods and to investigate the validity and reliability of the scale. The research was conducted on 417 (209 girls and 208 boys) undergraduate students in Selcuk University regarding functional foods. The participants were selected from different departments of Selcuk University using proportional cluster sampling method and the scale was repeated twice. Split-half test, Kuder-Richardson (KR 20) internal consistence coefficient and test- retest reliability methods were used to determine the validity of application during reliability test when examining the validity of content, view and structure of application. Seventy-seven questions that did not contribute to the result in the first application were removed from the achievement scale, and thus achievement scale was reduced to 45 items which were reorganized. Eleven more items that had little or no contribution were eliminated from 45 items of achievement test so that the scale was further reduced to 34 items. According to the data obtained from the scale applied, a significant difference was found between information levels of undergraduate student regarding functional foods (p<0.05). In calculating reliability, correlation between the first and the second application results was determined by using test-retest method and it was established that relationship between two applications was significant at 0.05 level. Reliability coefficient of the tool was found as 0.82 by split half test in the first application, while it was determined as 0.80 by Kuder-Richardson (KR-20) test. On the other hand, reliability coefficient of the tool was calculated as 0.91 in the second application.
Key words: Functional food, scale, validity, reliability, University students.