If you are not doing substantial gainful activity, we will then determine whether you have a medically determinable physical or mental impairment(s) (see §404.1520(a)(4)(ii)). Your impairment(s) must result from anatomical, physiological, or psychological abnormalities that can be shown by medically acceptable clinical and laboratory diagnostic techniques. Therefore, a physical or mental impairment must be established by objective medical evidence from an acceptable medical source. We will not use your statement of symptoms, a diagnosis, or a medical opinion to establish the existence of an impairment(s). After we establish that you have a medically determinable impairment(s), then we determine whether your impairment(s) is severe.
20 C.F.R. §404.1521