Measuring the Internal Consistency and Reliability of the Hierarchy of Controls in Preventing Infectious Diseases on Construction Sites: The Kuder-Richardson (KR-20) and Cronbach's Alpha

Abstract

Before initiating data collection, it is customary to assess the validity and reliability of the formulated question or instrument to ensure the collection of high-quality data for research purposes. Consequently, this study aims to evaluate the internal consistency of the data through a systematic analysis procedure to test the reliability of the adapted questionnaire. The adapted questionnaire is assessed using Kuder-Richardson 20 (KR-20) and Cronbach's alpha coefficients. The study on reliability was conducted using a sample size of 30. The Kuder-Richardson 20 (KR-20) test consists of a questionnaire comprising six questions and five questions with 5-point Likert scales to calculate Cronbach's alpha. For this study, the reliability assessment of Kuder-Richardson 20 (KR-20) revealed a robust correlation of 0.73 (within the range of 0.70–0.89). However, Cronbach's Alpha analysis indicates that the reliability test for the designed questionnaire yielded an acceptable result (0.74), falling within the recommended range of 0.7 to 0.8. The results obtained from the study suggest that there is a significant correlation between the research instrument and the variables being measured. Hence, to ensure the successful implementation of preventative measures against infectious diseases at the designated site, it is imperative to conduct the questionnaire development process accurately and establish its reliability.