VPI Stereo Disparity Estimator confidence threshold

What does the confidenceThreshold parameter do in VPI Stereo Disparity Estimator? Do disparity values with low confidence get set to 0? Or does something else happen down stream? Or is the parameter meant just for the user’s reference?

I have read the documentation page, VPI - Vision Programming Interface: Stereo Disparity Estimator, but did not find the details there. Is there a place that has more detailed documentation?