The Use of Likert Scale in Community Nutrition Research: Analysis of the Articles Published in Korean Journal of Community Nutrition

Ryu, Si Hyun; Yoon, Jihyun

Abstract

The purpose of this study was to examine if Likert scales had been properly utilized in community nutrition research. A total of 527 research articles published in the 32 issues of Korean Journal of Community Nutrition from the volume 5, issue 1 in 2000 to the volume 10, issue 2 in 2005 were screened and 55 articles were found to have utilized one or more Likert scales for the studies. Therefore, 109 Likert scales used in the 55 studies were reviewed regarding the name, statement and response items, reliability and validity check, and analysis method. The scales were mostly referred as Likert scales (60%) or Likert-type scales (27%). Some scales were found to be referred as Likert scales although they were Likert-type scales when judged based on the information given in the respective articles. However some scales couldn't be judged for the rightness of the names because the information given for the scales in the articles was not enough. About 23% of the scales consisted of items less than 6 or more than 30, and therefore found to be inappropriate. The percentage of the scales listing all the statement items in the articles was only 25%. Most of the scales (85%) included 5 response items, and the rest included 4 (7%), 7 (6%), or 3 (2%). The percentages of the scales including appropriate center and end items were only 2% and 22%, respectively. Less than half of the scales (41%) were found to have been checked for reliability and only one scale was reported to have been checked for validity. In some scales (6%), the responses were scored improperly for analysis. The responses to the scales were frequently found to have been analyzed by parametric statistics such as mean, ANOVA, t-test, and Pearson's correlation, which might be a problem depending on the size and distribution of study samples. In conclusion, there is much room for improvement in the use of Likert scales in community nutrition research.