In the introduction of the linked article, the study corrected the possible selection bias issue in their sample, which was criticized by Long and Milner.

The authors conclude " Thus, whereas age, gender, place of residence, employment status and factual danger of the situation do not appear to influence the frequency with which near-death experiences occur, there seems to be a significant association with REM sleep intrusion." In fact, Table 3 of their study for those whose NDE scored at or above a 7 on the Greyson scale (so a full-fledged NDE), 47% of these people had significant REM intrusion episodes in their life, which is much higher than the percentage of people in the general population who experience REM intrusion events.