Often peak-to-peak jitter is specified relative to RMS jitter. If one looks at the jitter distribution curve in the figure below, other points on the distribution curve can be used to specify jitter. These points are specified as integer multiples of the one sigma value. One specification that is often used is the 6-sigma value. Here, 99.999% of the jitter is accounted for with this value. A common rule used is that the peak-to-peak jitter is 6 times the RMS jitter value. This would be specified as Peak-to-Peak jitter @ 6 Sigma.
6 Sigma Peak to Peak jitter = 6*RMS jitter
Refer to application note AN-840 for more details. For other questions not addressed by the Knowledge Base, please submit a technical support request.