In any proceeding for the enforcement of a claim for compensation under this chapter, it shall be presumed in the absence of substantial evidence to the contrary
- 1. That the claim comes within the provision of this chapter;
- 2. That sufficient notice thereof was given;
- 3. That the injury was not occasioned by the willful intention of the injured employee to bring about the injury or death of himself or of another;
- 4. That the injury did not result solely from the intoxication of the injured employee while on duty.
- 5. That the contents of medical and surgical reports introduced in evidence by claimants for compensation shall constitute prima facie evidence of fact as to the matter contained therein.