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Introduction Postural control might be impaired after lower-limb amputation (LLA) and contributes to a high incidence of falling in individuals with LLAs with the risk of an injury occurring. There is no agreement on which objective assessment method is most appropriate for quantifying postural control during rehabilitation. Attention should be pointed to which test is most accurate at detecting a change in postural control after a given intervention. The objective of this quantitative prospective cohort pilot study was to compare four balance tests to determine their feasibility in detecting a change in postural control in persons with LLA (transtibial and transfemoral) during rehabilitation and prosthesis fitting. Methods Four different balance tests were used as primary outcomes before and after a 4-week rehabilitation program (n = 5). The tests used were Berg Balance Scale (BBS), Timed Up and Go (TUG), and force plate measurements in standing and seated position (FPMstand + seat). Secondary outcome was quality of life assessed by the EuroQol, 5 dimensions, 5 levels (EQ-5D-5L) questionnaire. Results All participants improved in BBS, TUG, and FPMstand. FPMseat showed varying results. The EQ-5D-5L questionnaire showed a slight improvement in quality of life in accordance with the changes in primary outcome measures. Conclusions A change in postural control during rehabilitation and prosthesis fitting in individuals with LLAs may be assessed by BBS, TUG, and FPMstand. A criterion standard for quantifying postural control is lacking. Hence, a combination of tests to measure and detect a change in postural control can be used. Present pilot study finds that BBS, TUG, and FPMstand may be measurements used for assessment of changes in postural control in the rehabilitation of individuals with LLAs.

The distinction between field and laboratory is classical in research methodology. In human-computer interaction, and in usability evaluation in particular, it has been a controversial topic for several years. The advent of mobile devices has revived this topic. Empirical studies that compare evaluations in the two settings are beginning to appear, but they provide very different results. This paper presents results from an experimental comparison of a fieldbased and a lab-based usability evaluation of a mobile system. The two evaluations were conducted in exactly the same way. The conclusion is that it is definitely worth the hassle to conduct usability evaluations in the field. In the field-based evaluation we identified significantly more usability problems and this setting revealed problems with interaction style and cognitive load that were not identified in the laboratory.