Results

The analysis revealed non-significant effects of imagery interventions that were (1) small and positive for functional mobility (g = 0.16), (2) large and negative for perceived pain (g = −0.86), and (3) large and positive for self-efficacy (g = 0.99). These effects were all non-significant, probably because the interventions administered and populations sampled in the studies were mostly heterogeneous. The observed null results might also reflect that existing studies on injury lack power. Hence, the effects of MI on bio-psychological variables warrant continued empirical investigation.