Concept of P-value

Abstract

P -value has been criticized because it is widely misunderstood and don′t tell the researchers what they want to know. Many clinical researches mistaken the conclusion of a significant P-value and may be exaggerate small and unimportant difference. In this regard, understanding of meaning and concept of P-value is critical to investigators as well as to readers. In brief, P-value is the probability of observing a difference equals or more extreme than what was actually observed, if the null hypothesis is true. It is not the proportion of chance that might cause the difference. P-value is not the probability of rejecting the null hypothesis, that probability called α (Type1 error). The smaller the P-value, the stronger the evidence against null hypothesis.

Keywords

• Hypothesis
• interpretation
• P-value
• significance