Experimental design and reporting standards for improving the internal validity of pre-clinical studies in the field of pain: Consensus of the IMI-Europain consortium

•Recommendations for improving the internal validity and reliability of pre-clinical pain studies are proposed.•Experimental design and conduct, and study reporting are the focus of the guidance.•Addressing any potential threats to internal validity and/or sources of experimental bias, as well as increasing reporting transparency should address a significant reproducibility concern.•Disseminating these Europain processes in the wider pain research community enables discussion.•Benefit from these guidelines will dependent on acceptance and disciplined implementation.