背景和目的：搭配第二任務而形成的雙任務計時起走測試可以用來預測老人衰弱與跌倒，過去研究只有使用一層難易度的第二任務。本研究採用了三種雙任務計時起走測試，目的在分別檢驗其三層難易度之間的表現是否確實不同。方法：本橫斷性研究收集了六十五名五十歲以上社區中老年人的資料（平均年齡71.5±8.1歲）。計時起走測試搭配三種第二任務，每一種第二任務皆有三層難度。其中，第一種為手部操作任務，為拿一杯水，水面高度距杯緣五、三及一公分。第二種為減數任務，為連續減數，分別減去三、七及十九。第三種為記憶任務，為購物清單之回憶，清單分別以間隔五、三及二秒的間距播放。使用重覆量數的變異數分析、菲德曼測試來分別檢驗三層難易度是否造成計時起走測試表現和第二任務正確率的差異。結果：伴隨手部操作與減數任務之計時起走測試之完成時間因第二任務難易度的差異而顯著不同（P<0.05)，事後比較的結果顯示，伴隨手部操作之計時起走測試之中等與困難程度間有顯著差異，伴隨減數任務之計時起走測試之簡單與中等程度間有顯著差異；但是伴隨記憶任務之計時起走測試完成時間則未因第二任務難易度之不同而呈顯著差異（P>0.05)。手部操作、減數任務與記憶任務之第二任務正確率皆隨著難易度之不同而呈顯著差異（P<0.05)。結論：本研究設計之計時起走測試伴隨三層難易度的手部操作和減數任務具有分層的難易度，可能可以應用在不同的族群。其中手部操作任務距杯緣三公分這一層難易度僅和距杯緣一公分的這一層難易度有計時起走表現的差異，顯示距杯緣三與五公分對中老年人之難度是相似的。而連續減數任務中，減七和減十九可能對中老年人而言難度亦相似。本研究計時起走測試伴隨記憶任務的三層難易度對計時起走完成時間並未造成影響1需要進一步的研究設計調整。未來研究應檢測三層難易度與不同之雙任務計時起走測試在不同族群應用時的信效度。（物理治療2015;40(1):11-17)

Background and Purpose: Performing a secondary task while at the same time executing Time Up and Go Test (TUG) could be used to predict elderly frailty and falls. Previous studies, however, utilized just one level of complexity of the secondary task. This study adopted three types of dual-tasking TUG tests, and aimed to test subjects’ performance difference under three-level complexity. Methods: This cross-sectional study recruited 65 community-dwelling over 50 (71.5±8.1 years). TUG were conducted with three types of secondary tasks. The TUG-manual involved carrying a cup of water with the surface of the water 5, 3 or 1 cm from the lip of the cup while walking. The TUGmath involved serial subtracting by 3, 7 or 19 while walking.
The TUGmemory involved memorizing a shopping list with 5-, 3- or 2-second temporal intervals while walking. Repeated measures ANOVA or the Friedman test was used to examine whether the three-level complexity of dual-tasking TUG resulted in significant differences in TUG and secondary task performances. Results: The time taken to complete TUG increased as the level of complexity increased in TUGmanual and TUGmath (P<0.05). Post hoc analyses revealed that performances on the TUGmanual tests involving carrying a cup of water with the surface of the water 3 and 1 cm from the lip of the cup were different from each other, and performances on the TUGmath tests involving serial subtracting by 3 and 7 were different from each other. The time taken to complete TUG did not increase as the level of complexity increased in the memory task (P>0.05). The accuracy of secondary task performance decreased as the level of complexity increased in all three types of TUG tasks (P<0.05). Conclusions: The three-level complexity of TUGmanual and TUGmath tests indeed posed different levels of challenge to our subjects and may be also suitable for applications in other populations. However, carrying a cup of water with the surface of the water being 3 or 5 cm from the lip of the cup was of the same level of complexity and needs further revision to make them differentiable in difficulty. The complexity levels of TUGmemory also need further modifications. It is important that future studies examine the validity and reliability of dual-tasking TUG with different levels of complexity in various populations.
(FJPT 2015;40(1):11-17)