Trend Score compares close prices between last close with previous closes by a certain period of time. It's like momentum but gives a score +1 when close price is equal to or above (defaultly) 10 bars ago and gives a score of -1 when below. calculation continues from default length to the 2 times of length.
Defaultly (for 10 bars length) If Trend Score converges to 10; that means there's a strong uptrend conversely if Trend Score converges to -10; that means a strong downtrend market is on.