1. Suggestion/Placebo Effects on Pain
Peter Staats, M.D., Hamid Hekmat, Arthur Staats 
Journal of Pain and Symptom Management 
Volume 15, Issue 4, Pages (April 1998)
DOI: /S (97)

2. Fig. 1.
Change in pain threshold from pretest to posttest in the positive placebo, negative placebo, and the control participants
Journal of Pain and Symptom Management  , DOI: ( /S (97) )

3. Fig. 2.
Change in pain tolerance from pretreatment to posttreatment in the positive placebo, negative placebo, and control participants
Journal of Pain and Symptom Management  , DOI: ( /S (97) )

4. Fig. 3.
Change in pain endurance from pretreatment to posttreatment reported by participants receiving placebo interventions as compared to the control
Journal of Pain and Symptom Management  , DOI: ( /S (97) )