Okla. Stat. tit. 12, § 2702
If scientific, technical or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training or education may testify in the form of an opinion or otherwise.
Laws 1978, SB 276, c. 285, § 702, eff. October 1, 1978.