Some of the work and research done by NIHR Involve, a national advisory group which is part of, and funded by, the NIHR. It supports active public involvement in NHS, public health and social care research. They develop capacity and capability for public involvement in research providing advice and a range of resources to support researchers and the public involved in research.
Plus work specific to Wales:
And their evidence library: https://www.invo.org.uk/resource-centre/libraries/evidence-library/