Dissenting Opinion by
Judge DiSalle :I respectfully dissent. Although it concludes that the referee erred in not admitting the death certificate as evidence of the cause of death, the majority holds that the error was nevertheless harmless. I cannot agree for two reasons. In the first place, Duquesne Light Co. v. Gurick, 46 Pa. Commonwealth Ct. 150, 405 A.2d 1358 (1979), holds that a doctor’s testimony that an occupational disease was “one of the causes of death” will support a claim for death benefits under Section 301(c)(2) of the Workmen’s Compensation Act, 77 P.S. §411(2). If the death certificate had been admitted, Claimant could have questioned Dr. Darkes as to whether anthracosilicosis was one of the causes of death. As it was, Dr. Darkes did try to explain the remarks on the death certificate as they related to causation. The referee did not allow him to do so, however, on the basis that the death certificate was not in *560evidence for that purpose. The referee’s error, therefore, prevented Claimant from making any attempt to meet the Guriclc test. Secondly, consistent with Castor v. Ruffing, 178 Pa. Superior Ct. 124, 112 A.2d 412 (1955), Claimant could have framed a hypothetical question to elicit Dr. Darkes ’ expert opinion on causation using the death certificate as the necessary factual basis for the question. We should not fault Claimant for failure to ask a hypothetical question when the referee effectively denied him the opportunity to do so. See Hoffman v. Commonwealth, 422 Pa. 144, 221 A.2d 315 (1966).
Where, as here, the orderly introduction of relevant evidence is thwarted at the outset by an erroneous ruling, the error is prejudicial and I would remand to the Board for a new hearing.