Nevertheless, peer review is not peer approval. When scientists feel that the weight of scientific evidence contradicts particular claims, then it is our responsibility to state so clearly. If we agree to provide reviews, we will ourselves contact the scientists who will provide the evaluations. We provide guidance to reviewers through our policies , and ensure that reviews are timely and complete. Reviews can be large or small, and involve one or many scientists.
Cost varies with the scale of the project.
Small reviews are typically carried out pro bono, or through reimbursement of expenses. Larger scale projects are tailored towards particular project needs. SEI policy is that reviews are NOT anonymous.