@article{19109,
  author = {Macedo L. and Herbert Rob and McAuley J. and Kamper S. and Maher C.},
  title = {Trial methodology and patient characteristics do not influence the size of placebo effects on pain. Meta-regression of trial-level factors},
  year = {2008},
  journal = {Journal of Clinical Epidemiology},
  volume = {61},
  number = {3},
  pages = {256-260.  },
  language = {eng},
}