One factor determining the quality of research is the researchers’ understanding, mastery, and use of scientific terminology. Incorrect use of the terms clinical significance and statistical significance often leads to an incorrect way of assessing the results. International studies use the concept of clinical significance to indicate the practical significance of a treatment effect. Clinical significance refers to differences in effect sizes that clinical experts consider to determine clinical decisions, regardless of their level of statistical significance (Todd et al., 1996). A clinically relevant finding is a characterization of patient outcomes. For example, in assessing clinical significance, attention is paid to the proportion of patients whose condition has improved and the individual-oriented indicators, but not the p-value.
Statistical significance refers to statistical methods that estimate the probability of an observed or higher degree of association between independent and dependent variables when the null hypothesis is true (Ma, 2000). Statistical significance does not imply the importance or practical value of the findings (Brahman, 1991). A statistically significant finding has little to do with the practice of medicine and no relevance to treatment. If only statistical significance is considered, researchers may report findings that are of little value in practice (Sandelowski & Leeman, 2012). Therefore, the effect size and p-value should always be reported. The effect size indicator facilitates decision-making about the practical relevance and application of the effect (Rutledge & Loh, 2004). Different variations in the statistical and clinical significance of the results are established in biomedical research, requiring different evaluations and actions. When analyzing options, it should be remembered that a clinically significant finding has implications for patient care that may not always be statistically significant.
References
Brahman, L. E. (1991). Confidence intervals assess both clinical significance and statistical significance. Ann Intern Med, 114(6), 515-517.
Ma, R. S. B. (2000). The role of qualitative research in broadening the evidence base’ for clinical practice. Journal of Evaluation in Clinical Practice, 6(2), 155-163.
Rutledge, T., & Loh, C. (2004). Effect sizes and statistical testing in the determination of clinical significance in behavioral medicine research. The Society of Behavioral Medicine, 27(2), 138-145.
Sandelowski, M., & Leeman, J. (2012). Writing usable qualitative health research findings. Qualitative Health Research, 22(10), 1404-1413.
Todd, K. H., Funk, K. G., Funk, J. P., & Bonacci, R. (1996). Clinical significance of reported changes in pain severity. Ann Emerg Med, 27(1), 485-489.