Two general approaches are used to deal with bias in health measurement. The first bypasses the problem and argues that health care should consider symptoms as presented by the patient, bias and all, given that this forms a part of the overall complaint: consideration of “the whole patient” is a hallmark of good care. From this viewpoint, it can be argued that the biases inherent in subjective judgments do not threaten the validity of the measurement process: health, or quality of life, is inherently subjective and is as the patient perceives it. The second viewpoint argues that this is merely a convenient simplification and that the interests of diagnosis and patient management demand that health measurements should disentangle the objective estimate from any personal response bias. As an example, different forms of treatment are appropriate for a person who objectively reports pain of an organic origin and for another whose pain is exacerbated by psychological distress; several pain scales we review make this distinction.