MYMOP, a patient generated measure of outcomes

EDITOR,-Charlotte Paterson's patient generated instrument to measure outcomes in primary care, the "measure yourself medical outcome profile" (MYMOP), seems to undermine most of the principles of psychometric theory and many of the purposes of research into outcomes as promoted recently. 1 The paper gives no account of how the measure was developed and does not provide a rationale for the selection of items or why it makes sense to sum them to provide an overall score.