Statistical significance is a useful guideline in interpreting research findings because it assesses the likelihood that results are due to chance alone. Statistical significance is based on a number called a “p-value.” By convention, results achieving a p-value less than 0.05 are called statistically significant, which simply means that the odds that a finding is due only to chance is only one in 20. This traditional cutoff for statistical significance is arbitrary, and a standardized incidence ratio that approaches but does not attain statistical significance may still be of interest.