Breaking Down Difficult Theory of Cronbach’s Alpha in Simple Concept: A Guide for Questionnaire Reliability Assessment for Medical Researchers

Abstract: Medical research frequently uses questionnaires to measure abstract notions like behavior, knowledge, and attitude. Determining these instruments' dependability is essential to arriving at accurate and significant interpretations and conclusions. Reliability is often measured by evaluating internal consistency. A statistic that measures internal consistency is Cronbach's alpha. Despite the tool's usefulness, medical undergraduates struggle to understand the concept due to their lack of statistical knowledge. The main focus of this guide is clarify the widespread misconception that higher alpha values are preferable. The articles explain through examples that good internal consistency is achieved by the items' shared meaning, which contributes to the creation of a consistent measure of the same construct. The range of Cronbach’s alpha is from 0-1. The range of alpha >0.7 to ≤ 0.9 is regarded as adequate to good reliability. In contrary, redundancy may also be represented by extremely high alpha values (>0.9). Medical researchers who comprehend Cronbach's alpha will be able to create better research tools and, in the end, produce better data for clinical and educational settings. Keywords: Medical research, Clinical research, Surveys, Reliability, Questionnaire.