SEM/MDC

3 PAPERS:

1. Almarwani, M., Perera, S., VanSwearingen, J. M., Sparto, P. J., & Brach, J. S. (2016). The test–retest reliability and minimal detectable change of spatial and temporal gait variability during usual over-ground walking for younger and older adults. Gait & posture, 44, 94-99.
2. Chen, C. H., Lin, S. F., Yu, W. H., Lin, J. H., Chen, H. L., & Hsieh, C. L. (2014). Comparison of the test-retest reliability of the balance computerized adaptive test and a computerized posturography instrument in patients with stroke. Archives of physical medicine and rehabilitation, 95(8), 1477-1483.
3. Huang, S. L., Hsieh, C. L., Wu, R. M., & Lu, W. S. (2017). Test-retest reliability and minimal detectable change of the Beck Depression Inventory and the Taiwan Geriatric Depression Scale in patients with Parkinson's disease. PLoS One, 12(9), e0184823.

QUESTIONS:
paper 1, page 97, results.
Fig. 1 illustrates the Bland–Altman plot for step time variability and plots of other spatial and temporal gait variability were similar. The Bland–Altman plots showed that there was no negative or positive trend; however, participants with greater gait variability tended to be less reliable.
Q1: 如何看出BA plots是否有趨勢? 只單就視覺判斷或有檢定方法?
Q2: 如發現像圖1所示，【分數越高，信度越低】，該如何建議? 或是對信度的解釋，需如何保守使用?

The gait variability values for younger adults were calculated using a mean of 38 steps, .......... Sensitivity analyses including the same number of steps in the calculations for younger and older adults did not significantly alter the findings.
Q1: 為何要提sensitivity analyses? 這與文章目的要討論的test-retest reliability有關嗎?

paper 2, page 1479, data analysis. (說不定可以來寫2種注意力工具的再測信度比較)
Data were analyzed with the IBM SPSS Statistics 19.0 program.To investigate the test-retest reliability of the Balance CAT and the Biodex Balance System, the Pearson correlation coefficient was used.

Q1: 為何不用ICC? 用Peason's r與ICC的差別為何? 當ICC的definition選擇consistency時，是否就與Peason's r相同?

In these formulas, SD is the SD of all scores of 2 sessions’ assessments, ....... The
multiplier of the square root of 2 refers to the additional uncertainty introduced by the inclusion of scores from 2 separate assessments. 
Q1: 根號2的意義為何? 若連續施測3次，是否修正為【根號3】?

paper 3, page 3/9, data analysis. 
The MDC% was then calculated by dividing the MDC by the maximal score of the measure [24]. An MDC% < 30% is considered acceptable, and < 10% is considered excellent [24].

Q1: MDC%的用意?其分母為maximal score或mean的選擇考量為何?對判斷標準的選擇的影響?

以上問題，請上課的夥伴協助釐清。
若有其他問題，亦歡迎提出並寫下紀錄，俾利共同精進與提升學習效率。

愛因斯坦名言：

宇宙中唯獨兩樣事物為無限：宇宙的大小，與人的無知。而宇宙的大小我卻不能肯定。

• 原文:Zwei Dinge sind unendlich: Das Universum und die menschliche Dummheit. Aber beim Universum bin ich mir nicht ganz sicher.

所以，在這個無限大的無知當中，我們需要的是謙卑的學習。