Even quite minor CPX complexes can have a major effect on QWB. For example, wearing eyeglasses (weight = 0.101), having a runny nose ( 0.170), and breathing polluted air ( 0.101). Such symptom/problem weights are stated by Kaplan and Anderson (1988b) to allow the health status index to become "very sensitive to minor top end variations in health status". However the "minor" adjustments seem to have the capacity to overwhelm the function scales. Thus the need to wear glasses ( 0.101) causes greater reduction in wellness than being in a wheelchair ( 0.060 or 0.077). This is not necessarily a problem if other aspects of the function scales always also contribute in such cases, but the fact remains that the scales are deemed to be independent and linearly added in the QWB model.