{'fraction_non_alphanumeric': 0.04195804195804196, 'fraction_numerical': 0.019425019425019424, 'mean_word_length': 4.946882217090069, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
THE RELIABILITY OF CLINICAL BALANCE TESTS UNDER SINGLE-TASK AND DUAL-TASK TESTING PARADIGMS IN UNINJURED ACTIVE YOUTH AND YOUNG ADULTS.

Background
Previous researchers have suggested that balance control deficits are detected more accurately with dual-task testing than single-task testing. However, it is necessary to examine the clinimetric properties of dual-task testing before employing it in clinical and research settings.


Objective
To examine and compare the relative and absolute reliability of the Balance Error Scoring System (BESS), Tandem Gait Test (TGT), and Clinical Reaction Time (CRT) under single and dual-task conditions in uninjured active youth and young adults.Study Design: Single-group, repeated-measures study.


Methods
Twenty-three individuals [9 female; median age 17 years] completed three trials of the BESS, TGT, and CRT under single and dual-task testing conditions during testing session one. Two raters assessed participants to assess inter-rater reliability. Either later on the same day or the following day, the protocol was repeated by one rater to assess intra-rater reliability. The average of three trials was used to calculate intra-rater (between-session) and inter-rater (within-session) intraclass correlation coefficient (ICC), standard error of measurement (SEM), minimal detectable change (MDC), and Cohen's Kappa coefficient for tests as appropriate under both conditions. Bland-Altman plots (mean difference and 95% limits of agreement) were used to assess for a systematic error associated with a learning effect.


Results
Only one participant attended the second session on the following day, while 22 participants (95%) attended the second session within four hours after testing session one. Under single-task testing, estimated ICCs, SEMs, MDCs, and Kappa coefficients ranged from 0.24 to 0.99, 0.3 to 23, 0.8 to 64, and 0.03 to 0.64, respectively. Under dual-task testing, estimated ICCs, SEMs, MDCs, and Kappa coefficients ranged from 0.70 to 0.99, 0.4 to 17, 1.1 to 47, and 0.39 to 0.83, respectively. A learning effect was identified for all tests under all conditions.


Conclusion
The BESS is the only clinical test that demonstrated acceptable reliability for clinical use under single-task testing conditions. The BESS, TGT, and CRT all demonstrated acceptable reliability for clinical use under dual-task testing conditions. A practice session should be used to reduce the possible learning effect seen. Further studies examining sources of the systematic error observed are needed.


Level of Evidence
2b.