Lack of statistical significance mistaken for lack of an effect and too much emphasis on the presence of an effect where results are statistically significant.
Emphasis on size, precision and clinical significance of effect. Incorporation of GRADE ratings can help to contextualise the numerical results and reduce the reliance on reporting statistical significance.
‘The estimated risk ratio for [outcome] was 0.92 (95% CI 0.78 to 1.32), 12 studies, 1437 participants). We rated this as high quality evidence since the confidence intervals do not include a clinically important difference of X%.’
‘Compared with control the difference in quality of life scores with intervention was 3.2 [units] higher with intervention (95% CI 1.2 to 5.2; 11 studies, 1365 participants). We downgraded the quality of evidence from high to moderate due to inconsistency in the direction and magnitude of effects across the studies (I square 65%).’