Any professional who renders services upon which you or others rely can commit malpractice. Often, the professional is licensed or regulated by the state. Attorneys, Doctors, Chiropractors, Accountants, Brokers, and Architects are licensed.
Accountants, attorneys, actuaries, chiropractors, dentists, physicians, psychologists and therapists are typically the persons named in a "malpractice action". When others engage in malpractice, the action is usually not specifically called malpractice, but is called negligence. In actual practice, only those who hold themselves out as having special skills or abilities are held accountable in malpractice litigation.