Introduction:  Results from several studies showed that subjects’ ability to perform well in the focused analgesia selection test (FAST) (i.e., low variability / high reliability) varies among people, and that this is related to placebo analgesia. In the context of RCT, training aimed to improve pain reporting reliability resulted with diminished placebo response. The aims of the current study were to assess: (1) if in experimental laboratory settings, subjects ability to reliably report pain could be improved by training; and (2) if trained subject will demonstrate lower placebo response.
Methods:   Healthy subjects were recruited into an experimental  randomized study, which comprised of two stages.   After completing a baseline visit, subjects were randomized into one of two parallel arms (stage 1) to Evoked Pain training (EPT) or no-training (control).   Upon completion of the first stage, all subjects enrolled into a randomized cross-over two-arms experimental study of ibuprofen and placebo (stage 2).
Results: 100 subjects (18-31 YO, 58 F) were recruited and completed 1st visit. 88 subjects completed the entire study (41 EPT, 47 control).  Mean FAST outcomes significantly improved upon training (Friedman’s test, chi-square 14.36; P<0.05, chi-square 7.02; P=0.07; ICC and R2, respectively). Post hoc Wilcoxon test revealed significant differences between baseline and each of the EPT visits (P<0.05 for all). Treatment responses significantly differed between the EPT and Control groups. As such, in the Cold Pain threshold (CPT) model, both placebo response and treatment difference (Mann-Whitney, P=0.001 for both) differed between groups. The EPT group showed no placebo response. 
Conclusions: Evoked pain training improved subjects' ability to reliably report pain. As in previous clinical studies, the results of the current experimental study showed that improved ability to reliably report pain is related with reduced placebo response and improved treatment response.

THE EFFECTS OF TRAINING AIMED TO INCREASE PAIN-REPORTING ACCURACY ON THE PLACEBO RESPONSE