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.
Correlations among dream recall frequency, dream report length, and visual memory were estimated for 50 subjects. The previously observed relationship between dream recall frequency and visual memory was confirmed, but visual memory did not influence the length of dream reports.
People with higher verbal creativity scores tend to report shorter dreams. In a study of 32 participants who completed a verbal creativity test and kept a dream diary for two weeks, those with high creativity scores reported significantly shorter dreams. The finding suggests that factors such as visual memory may influence the length of dream reports.