A comparison of placebo and no-treatment during a hypnotic clinical trial.
OBJECTIVE
Sleep parameters commonly improve during placebo treatment in insomnia clinical trials. We examined whether the improvement seen with placebo was related to taking pills or other non-specific factors.


METHODS
95 insomniacs took either a placebo pill (pill+) or no pill (pill-) on nights of their choosing over 12 weeks.


RESULTS
Pills were consumed on about half of the nights. Consistent improvement was seen with reduced reported sleep latency, wakefulness after sleep onset, number of awakenings, and total sleep time over the 12 weeks for both the pill+ and pill condition. A difference between pill+ and pill- was detected only for total sleep time, and this difference favored pill+.


CONCLUSIONS
This study suggests that improvement seen during placebo treatment is more related to non-specific factors of participating in clinical trial than to pill taking behavior.
Mccall
W V
WV
Department of Psychiatry and Behavioral Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1071, USA. vmccall@wfubmc.edu
Perlis
M L
ML
Tu
X
X
Groman
A E
AE
Krystal
A
A
Walsh
J K
JK
D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D015990:Placebo Effect; D010919:Placebos / Q000008:administration & dosage; D016032:Randomized Controlled Trials as Topic; D007319:Sleep Initiation and Maintenance Disorders / Q000188:drug therapy* / Q000503:physiopathology; D012894:Sleep Stages / Q000187:drug effects / Q000502:physiology; D013997:Time Factors
D006993:Hypnotics and Sedatives; D010919:Placebos