WinLTP
Version 2.20b
Leading-Edge Features
Special Features
Ordinary Features
Additional Features
Maximum Slope Measurement
 

WinLTP has three methods of measuring slope: 1) Maximum Slope, 2) the Begin -> End Times which measures the slope from beginning time point and to the end time point, and 3) the Low% -> High% Peak Amplitude which measures the slope from the beginning time point (where the amplitude is say 20% of the Low% Peak Amplitude value) to the ending   time point (where the amplitude is say 80% of the High% Peak Amplitude value).

Of these, the Maximum Slope measurement is usually the most reliable and least fussy.

To use the Maximum Slope, you set the MaxSlope time field ("1 ms" in the figure below) so that it is smaller than the BegTime/EndTime range ("2 to 8 ms after pulse" = 6 ms).  The 1 ms MaxSlope (marked by the red line) lies within the 6 ms BegTime/EndTime range (marked by solid vertical lines on the trace).

In the example below, the MaxSlope algorhythm starts at 2 ms after the pulse and calculates the value of a 1 ms slope every 0.1 ms until the EndTime point is reached (between 7 and 8 ms after the pulse).  The absolute largest positive or negative slope will be the slope chosen.  This is the Maximum Slope, and is plotted with the red slope line.

For more information see Section 4.11.4 in the on-line WinLTP Manual.