The near-death experience scale. Construction, reliability, and validity.

Near-death experiences (NDEs) have been described consistently since antiquity and more rigorously in recent years. Investigation into their mechanisms and effects has been impeded by the lack of quantitative measures of the NDE and its components. From an initial pool of 80 manifestations characteristic of NDEs, a 33-item scaled-response preliminary questionnaire was developed, which was completed by knowledgeable subjects describing their 74 NDEs. Items with significant item-total score correlations that could be grouped into clinically meaningful clusters constituted the final 16-item NDE Scale. The scale was found to have high internal consistency, split-half reliability, and test-retest reliability; was highly correlated with Ring's Weighted Core Experience Index; and differentiated those who unequivocally claimed to have had NDEs from those with qualified or questionable claims. This reliable, valid, and easily administered scale is clinically useful in differentiating NDEs from organic brain syndromes and nonspecific stress responses, and can standardize further research into mechanisms and effects of NDEs.