Reliability in dream research: a methodological note.
Consciousness and Cognition December 1, 2001 M Schredl, A T Funkhouser, C M Cornu et al.
Dream recall and dream length are stable over time, but dream characteristics like bizarreness and emotional tone fluctuate greatly within individuals. Analyzing a series of 20 dreams from healthy elderly persons obtained through weekly telephone interviews, internal consistency and retest reliability after 4 or 22 weeks were computed. To obtain reliable measures of these fluctuating dream variables for correlational studies with waking-life traits, researchers need to collect as many dreams as possible (about 20) within a very short time period. Further research is needed to extend these findings to diary and laboratory dreams.