A study published in the Australian Journal of Parapsychology compares intentional or will-induced OBE's with spontaneous OBE accounts. Statistical analysis confirms something very familiar to lucid projectors: that intentional OBE's have a higher incidence of the sensation of "take off."
12 Issue 2 (2012)
Research note: Induced out-of-body experiences are associated with a sensation of leaving the body
Abstract: Individuals who have had an out-of-body experience (OBE) report that the centre of their awareness appears to, temporarily, shift to a location that is spatially distinct from the location of their physical body. Research suggests that some OBErs report a sensation of leaving their physical body prior to their OBEs, while others instead report spontaneously finding themselves outside of their body. The present study evaluated data collected from 194 participants who claimed to have had an OBE. Instances of spontaneous and autonomously induced OBEs were considered. Binary Logistic Regression identified one item that predicted whether a participant was more likely to have had an induced, rather than a spontaneous, OBE: whether a participant had experienced a sensation of leaving their physical body prior to the OBE.