Reproducibility of balance measures using motion sensors in smartphone technology to measure balance: preliminary result

PURPOSE: This pilot study was to determine the reproducibility of the output generated by Smartphone accelerometers when used for balance assessment. METHODS: 61 healthy individuals (28 male, 33 female; mean age = 23.8+6.2yr) performed a static Single Leg Athlete's Test (SLS) and a Tandem Stand with eyes closed (TSEC) for 10 seconds each. A commercially available Smartphone was used to determine Anterior/Posterior stability. 4 trials were completed for each test with 1 minute rest between trials. RESULTS: For each balance assessment, one-way ANOVA was performed and pairwise comparisons determined. For SLS, no significant differences were noted between trials (p = 0.05). For TSEC, trial 1 was significantly different from trials 2, 3, and 4 (p < 0.05). Additionally, for TSEC, a significant difference was observed between trials 2 and 4 (p < 0.05), however neither trial 2 nor 4 was significantly different than trial 3. For SLS, no significant differences were observed between trials 2, 3, or 4. CONCLUSION: No significant differences were found between trials for SLS, the first trial of TSEC was found to be significantly different than subsequent trials. This may indicate a familiarization trial is necessary if Smartphone technology is to be used for conducting balance assessments.