In Adams v. Chevron, U.S.A., Inc., 589 So. 2d 1219 (La.App. 4 Cir.1991), writs denied, 592 So. 2d 414, 415 (La.1992), the fourth circuit adopted the Christophersen v. Allied-Signal Corp., 939 F.2d 1106 (5th Cir.1991) interpretation of Federal Rule of Evidence article 403 for the evaluation of the admissibility of expert testimony under Louisiana law. That four-inquiry approach is as follows: (1) whether the witness is qualified to express an expert opinion; (2) whether the facts upon which the expert relies are the same type as are relied upon by other experts in the field; (3) whether in reaching his conclusion the expert used well-founded methodology; (4) assuming the expert's testimony passes these tests, whether the testimony's potential for unfair prejudice substantially outweighs its probative value under the relevant rules. (Adams, 589 So. 2d at 1223.)