Objectives: In 2003, based on a review of 7 studies, Rose et al concluded that at least one third of patients report significant memory loss 6 months or more after electroconvulsive therapy (ECT). However, few details on the included studies were given. The present study evaluates factors that may have influenced the results.
Methods: The 7 studies were scrutinized as to the 6-month assessment criterion, whether the data represent ECT-treated patients in general, specification and significance of the memory loss, stimulus type, and electrode placement.
Results: In 3 studies, the 6-month inclusion criterion was not met, including 1 study with 98% satisfied patients and 1 study with only 37% valid response rate. Two other studies selected individuals from user/advocacy groups generally biased against ECT and were probably overlapping. The significance of memory problems was not mentioned in any of the studies. Two studies reported that 30% and 55% of patients treated with bilateral ECT in the 1970s felt they had persistent memory gaps around the time of treatment, but the long-obsolete sine wave stimulus type was used. The results mostly concerned bilateral ECT, whereas unilateral ECT seemed to cause little complaints.
Conclusions: Data used by Rose et al are severely flawed, making their results inconclusive and misleading.