An examination of group agreement among functional ankle instability participant inclusion criteria

Functional ankle instability (FAI) has been commonly identified in the literature as a cause of ankle injury and dysfunction. However, the participant selection criteria for FAI research have not been consistent. Numerous authors have used various selection criteria, with seemingly no two criteria being alike. Although these inconsistencies in FAI research participant selection criteria may explain the contradictions that have been reported in FAI research, the true nature of these selection criteria differences is unknown. It is uncertain exactly if, and to what magnitude, these selection criteria differed. The purpose of this study was to examine group agreement regarding selection criteria among authors who recruit participants with self-reported functional ankle instability. In addition, the prevalence of functional ankle instability will be identified. One hundred ninety physically active high school and college-aged participants, (74 men, 19.0 yrs ± 2.49, 115 women, 18.5 yrs ± 2.13) were asked to respond to a questionnaire consisting of 113 criteria items that represented a culmination of 25 authors\u27 inclusion criteria used for published research addressing FAI. Percent agreement of eleven broad inclusion criteria, proportion of agreement and kappa scores, and the prevalence of FAI were calculated based upon the 25 authors\u27 inclusion criteria. Percent agreement suggested low overall agreement in eleven broad inclusion criteria authors used to select participants with FAI. Only three broad inclusion criteria, including history of ankle sprain, sprain frequency, and self-reported instability, were incorporated by at least 21 of the 25 authors, whereas eight of the categories were incorporated by less than 12 of the authors. The results also indicated low agreement and kappa scores for the 2 x 2 contingency tables (m=85.8%; k=. 10) and the 3 x 3 contingency tables (m=55.1 %; k=.15). Prevalence ranged from zero to 31 percent. Overall these results indicate that FAI research inclusion criteria is inconsistent, has potentially led to the study of participants with different characteristics, and cast doubt on the appropriateness of comparing previous FAI research