title: Clinical relevance vs. statistical significance: Using neck outcomes in patients with temporomandibular disorders as an example.
abstract: Statistical significance has been used extensively to evaluate the results of research studies. Nevertheless, it offers only limited information to clinicians. The assessment of clinical relevance can facilitate the interpretation of the research results into clinical practice. The objective of this study was to explore different methods to evaluate the clinical relevance of the results using a cross-sectional study as an example comparing different neck outcomes between subjects with temporomandibular disorders and healthy controls. Subjects were compared for head and cervical posture, maximal cervical muscle strength, endurance of the cervical flexor and extensor muscles, and electromyographic activity of the cervical flexor muscles during the CranioCervical Flexion Test (CCFT). The evaluation of clinical relevance of the results was performed based on the effect size (ES), minimal important difference (MID), and clinical judgement. The results of this study show that it is possible to have statistical significance without having clinical relevance, to have both statistical significance and clinical relevance, to have clinical relevance without having statistical significance, or to have neither statistical significance nor clinical relevance. The evaluation of clinical relevance in clinical research is crucial to simplify the transfer of knowledge from research into practice. Clinical researchers should present the clinical relevance of their results.
authors.affiliation: Faculty of Medicine and Dentistry, Alberta Research Centre for Health Evidence, 11402 University Avenue, Edmonton, Alberta, Canada. sla4@ualberta.ca
authors.forename: Susan
authors.initials: S
authors.lastname: Armijo-Olivo
authors.forename: Sharon
authors.initials: S
authors.lastname: Warren
authors.forename: Jorge
authors.initials: J
authors.lastname: Fuentes
authors.forename: David J
authors.initials: DJ
authors.lastname: Magee
mesh_terms: D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000503:physiopathology; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D004576:Electromyography / Q000379:methods; D005080:Exercise Test / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D053580:Muscle Strength / Q000502:physiology; D009334:Neck Muscles / Q000503:physiopathology*; D019547:Neck Pain / Q000453:epidemiology* / Q000503:physiopathology* / Q000628:therapy; D010147:Pain Measurement; D010808:Physical Examination / Q000379:methods; D011187:Posture / Q000502:physiology; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013705:Temporomandibular Joint Disorders / Q000453:epidemiology* / Q000503:physiopathology* / Q000628:therapy