Will it hurt less if I believe I can control it? Influence of actual and perceived control on perceived pain intensity in healthy male individuals: a randomized controlled study

We explored the effects of uncontrollability and subjective helplessness (SHL) on perceived pain intensity (PPI) in 64 healthy men randomly assigned to groups receiving controllable (C) or uncontrollable (UC) painful electric skin stimuli. SHL (d = 1.43), perceived unpleasantness (d = 1.03), and PPI (d = 0.58) were more pronounced in the UC group than in the C group. Multiple regression and bootstrap analyses for testing mediation showed a direct relationship between stressor uncontrollability and PPI (r = 0.28; P < .05), which disappeared when adjusted for the SHL increase (β = 0.49, P < .001). SHL changes were associated with objective uncontrollability (r = 0.59, P < .001). PPI and unpleasantness were positively correlated (r = 0.37, P < .01). The study suggests that the effect of objective controllability on pain intensity ratings is mediated mainly by ratings of SHL.