(dissenting) .
The question presented to this court is whether the testimony of a clinical psychologist is competent in workmen’s compensation proceedings to establish causation for mental disability. The majority holds that it cannot be competent for that purpose, basing their holding upon the premise that “medical” testimony is necessary to show causation in workmen’s compensation proceedings. This premise has no statutory basis, but has often been stated in a modified form in workmen’s compensation decisions, to the effect that unless apparent to a layman the physical condition and causal connection can only be *476determined by expert “medical” testimony. In my opinion the statements in prior Arizona decisions must be considered in the factual context given, that is, in a factual context where the only testimony presented was that of laymen witnesses and of medical doctors. To me the statement only gives recognition to a problem of proof. For example, the causal relationship between a compound fracture and the industrial accident could generally be established by the testimony of the layman, whereas in other circumstances expert witness testimony would be necessary, with that expert witness generally being a medical doctor. I do not know of any legal principle which would support the exclusion of other expert testimony coming from witnesses qualified in other recognized areas of expertise. Thus in Chalupa, supra, the Arizona Supreme Court recognized that a non-medical doctor, a chiropractor, could be an expert witness as to causation in the area of his expertise. Likewise, in my opinion, a licensed clinical psychologist could give expert causation testimony within the area of his expertise, whether considered “medical” or otherwise. I cannot ascribe any magical or talismanic effect to the Supreme Court’s prior use of the word “medical” under these circumstances.