Clinical Significance

[Page 701]Clinical significance focuses on how a treatment alters symptoms to improve day-to-day life in a way that the average person might appreciate. The idea of clinical significance grew out of consumer frustration with interpretations of the impact of interventions. Many members of the lay public had trouble making sense of the treatment outcome literature, in part because statistical significance confounded effect sizes (i.e., the magnitude of effect) with sample sizes (i.e., the number of observations in a research sample). Consumers were unclear if a therapy ended up looking helpful simply because experiments used huge samples. Many therapies were reported as helpful (or not) based on statistical significance, whereby a therapy was deemed to be helpful when mathematical values exceeded certain agreed-on thresholds. However, statistical ...