Table 1.

The number of subjects and slip trials used for deriving and verifying the limits of recovery.

Trials	Original Studiesa		Present Study		Outcome
	Number of Subjects	Number of Samples	Number of Subjects	Number of Samples	Fall	Recovery
1st e	84	75b	69c	69	11	58
2nd and 3rd f	39	78	38d	76	7	69

^aData from (Bhatt and Pai, 2008a; Bhatt and Pai, 2008b; Bhatt and Pai, 2009).

^bAfter excluding 4 trials with technical errors (e.g., platforms trigger problem and loss of markers) and 5 trials identified as harness-assistance. A trial is identified as a harness-assistance if the peak load cell force is never greater than 30% body weight and the peak value of the moving average load cell force is not less than 4.5% body weight over any 1-second period after the slip onset.

^cAfter excluding 4 two-step falls and 2 three-step falls. The number of recovery step is determined as the number of the steps following the slip onset and before the instant when the load cell force reaches 30% body weight. A trial whereby the subject took more than one recovery steps would be categorized as a multiple-step fall.

^dAfter excluding a two-step faller.

^eTrials used to determine the boundary and the limits of recovery.

^fTrials used to verify the boundary.