that marijuana must also stimulate the appetite of a cancer patient. The only basis for his conclusion was his opinion that: "I think almost everyone over the age of 15 in this society knows that marijuana makes you hungry.” On this record, we conclude that Mr. Randall’s opinion that marijuana is beneficial in the treatment of cancer was based on nothing more than pure speculation. Although Pittman properly points out that Mr. Randall has a considerable amount of practical experience concerning the medical uses of marijuana, his practical experience does not obviate the need for a scientific basis for his opinion. In the absence of a scientific basis, Mr. Randall’s opinion lacked an adequate foundation and was properly excluded by the trial court. See McGrath, 63 Wn. App. at 178 (<HOLDING>). Moreover, any error in the trial court’s
holding the experts opinion testimony lacked a proper foundation when there was no physical evidence of sexual abuse and the experts admitted that their conclusions were based solely on the childrens statements that they had been abused holding that trial court didnot abuse its discretion in admitting experts opinion which was based primarily on his own experience in the field holding even though experts are permitted to give an opinion they may not offer an opinion regarding the credibility of others holding that an experts opinion must be based on facts in evidence or within his or her knowledge and that the admission of an experts opinion is reviewed for an abuse of discretion holding that trial court abused its discretion in admitting alcoholism experts opinion that the insureds mental capacity was so impaired at the time of the shooting that he could not form intent to injure opinion lacked an adequate foundation when there was no scientific basis regarding the effects of intoxication on mental capacity to form intent to injure