Shirley A. Morrison appeals from a post-trial order of the Court of Common Pleas of Allegheny County granting Schleifer’s Ambulance Services (Ambulance Service) a new trial. The issue raised in this appeal is whether the trial court erred in granting a new trial because evidence pertaining to the conduct of the ambulance crew immediately after a passenger escaped from the ambulance and fell to his death was improperly admitted into evidence. For the following reasons, the trial court is reversed.1
I
On July 29, 1986, Mrs. Morrison’s husband, George Morrison, was being transported by Ambulance Service from a police station in Rankin, Pennsylvania to Woodville State Hospital (Woodville), a hospital operated by the Commonwealth of Pennsylvania, Department of Public Welfare, Office of Mental Health (OMH). Mr. Morrison was a mental health patient at Woodville and was on a brief visit home when he began to hallucinate and became violent. Officer Mudd, the local Chief of Police, transported Mr. Morrison from his home to the police station and OMH arranged for Ambulance Service to transport him from the police station to Woodville. While the ambulance was traversing the Fort Pitt Bridge crossing the Monongahela River, Mr. Morrison forced his way out of the ambulance, ran a short distance and fell over the side of the bridge to his death. Mrs. Morrison filed a wrongful death and survivor action against OMH, J.P. Harika, M.D.2 and Ambulance Service alleging, inter alia, that Ambulance Service was negligent by failing to assess Mr. Morrison’s condition; failing to restrain, control and watch him; allowing him to escape the ambulance; and failing to remain at the scene to assist the rescue squad.
*249Prior to trial, Ambulance Service filed a motion in limine to preclude evidence regarding the fact that the ambulance crew left the scene of the accident after Mr. Morrison fell from the bridge. Ambulance Service reasoned that since the ambulance crew was unable to assist Mr. Morrison from their position on the bridge, evidence regarding their actions after the fall is prejudicial and that such prejudice outweighs any probative value; and since there is no evidence that Mr. Morrison could have been rescued or would have survived the fall, the contested evidence is irrelevant. Mrs. Morrison asserted that the evidence is admissible and relevant because it is probative of the ambulance crew’s lack of proper training and continuing negligent activity; and its probative value is not substantially outweighed by any prejudice to Ambulance Service’s case. The trial court denied Ambulance Service’s motion in limine.
At trial, the ambulance crew and Theodore J. Schleifer, the owner of Ambulance Service, testified. Bernard J. Jozwiak testified that the extent of his training in transporting mental health patients was his boss’ advice to treat the patients like human beings, and he had not attended any courses, classes or training seminars. Further, he was in the back of the ambulance with Mr. Morrison when he climbed into the front passenger seat and escaped through the door on the passenger side; he followed Mr. Morrison through the passenger door and ran after him; and after Mr. Morrison leaned over the rail and fell, the ambulance crew drove to a telephone where they called 911 and Mr. Schleifer who instructed them to return to the base where they discussed the incident with Mr. Schleifer. John C. Fritzius, the driver, added that he had emergency medical training (EMT) at a community college but did not pass the course; and after they returned to the base he and Mr. Jozwiak transported another patient before going to the police station with Mr. Schleifer. Theodore J. Schleifer testified that he knew from his EMT training that state law required that an attendant accompany a patient in the back of an ambulance; and the only training that he provided his employees regarding transporting people with *250mental disorders was Ms instruction that attendants treat mental patients like human beings.
Both parties presented expert witnesses who testified regarding local and national standards of care and specifically addressed the degree of traimng an ambulance crew should have; how an ambulance crew should assess a patient’s condition; what restraints a trained ambulance crew would use when transporting a mental patient; and how a trained or reasonable ambulance crew would have reacted to an escape such as tMs one. Mrs. Morrison’s experts opined that it would not have been possible for Mr. Morrison to have escaped in the fasMon that Ambulance Service claims he did; and that a trained ambulance crew presented with tMs situation would have left one member of the crew behind while the other sought assistance. Ambulance Service’s expert opined that although common sense should have told the ambulance crew to stay around after the fall, leaving was not a breach of their duty. Further, Ambulance Service presented the video tape deposition testimony of a doctor who testified that the primary cause of Mr. Morrison’s death was a forceful blow to the head which knocked him unconscious and that he drowned.
Mrs. Morrison also presented the testimony of two fact witnesses to challenge the credibility of Ambulance Service’s witnesses. An electrician who was working on a temporary dock below the Fort Pitt Bridge testified that after he heard an object strike the edge of the dock and fall into the water, he looked up to the bridge and saw two men looking over the side and an ambulance with all of the doors open, including the back door. A nurse at Woodville testified that she received a telephone call from an excited and upset male who identified Mmself as an ambulance driver and told her that on the way to Woodville, George Morrison jumped out of the back of the ambulance, bolted to the railing, jumped over the railing and Mt the dock.
After the close of evidence, the trial court instructed the jury that its verdict should be based on the evidence and the application of legal principles, not on emotions, and that the mere happemng of an unfortunate event which results in *251death does not automatically give rise to the right to compensation from a party who has some connection with the event. The court further instructed that the burden of proof is on Mrs. Morrison to establish the liability of Ambulance Service; if the jury determines that Mr. Morrison died from the blow on the head, then the ambulance crew’s failure to remain, right or wrong, did not have anything to do with his death; and that an ambulance service which holds itself out to the public to accept anybody who wishes to use its service is called a common carrier for hire and is held to the highest degree of care.
The jury returned a verdict for Mrs. Morrison assessing the causal negligence at 75% attributable to Ambulance Service, 25% attributable to OMH, no negligence attributable to Mr. Morrison, and awarded $450,000 in damages. Ambulance Service filed post-trial motions and the trial court granted Ambulance Service a new trial because it determined that it erred in permitting testimony regarding the ambulance crew’s actions in leaving the scene of the accident. The trial court reasoned that the actions were represented as cold and callous indifference to life and should not have been admitted since Mr. Morrison was probably already dead when the ambulance crew left the scene of the accident and, therefore, the actions did not contribute to his death.3
II
The trial court has the inherent power to grant a new trial. Kralik v. Cromwell, 435 Pa. 613, 258 A.2d 654 (1969). On appeal from an order granting a new trial, this Court’s scope of review is limited to determining whether the trial *252court abused its discretion or committed an error of law which controlled its decision to grant the new trial. Gilligan v. Shaw, 441 Pa. 305, 272 A.2d 462 (1971); Penneys v. Segal, 410 Pa. 308, 189 A.2d 185 (1963). Ambulance Service primarily argues that the abuse of discretion standard is applicable herein since the decision to exclude the evidence was a discretionary ruling; and, in the alternative, since the trial court did not certify or state that this was the sole and exclusive reason for granting a new trial, this court can affirm the grant of a new trial for any erroneous application of law found in the record.
Ambulance Service’s first argument is without merit because the decision for review before this Court is not the discretionary ruling to exclude evidence, but rather whether the reason the trial court gave for granting a new trial was in itself an error of law. Second, the trial court need not certify or state that the reason it granted a new trial was the sole and exclusive reason; contrariwise, all that is required is that the reason “clearly appears, either by certificate of the trial court or in its opinion on the new trial motion____” Keefer v. Byers, 398 Pa. 447, 449, 159 A.2d 477, 478 (1960). Accordingly, the issue here is whether, in a negligence case, evidence which is offered to prove breach of a duty need also be probative of causation to be relevant and therefore admissible.
The rules of evidence in Pennsylvania provide that evidence is admissible when it is relevant to a fact sought to be proved. Martin v. Soblotney, 502 Pa. 418, 466 A.2d 1022 (1983). Evidence is relevant when it tends to make a fact more or less probable and it need not conclusively prove the proposition for which it is offered. Id.; Leonard Packel & Anne B. Poulin, Pennsylvania Evidence § 401, at 122 (1987) (quoting J. McCormick, Evidence § 185, at 542 (3d ed. 1984)). However, relevant evidence may be excluded if its probative value is substantially outweighed by the danger of unfair prejudice or confusion. Whistler Sportswear, Inc. v. Rullo, 289 Pa.Superior Ct. 230, 433 A.2d 40 (1981). Prejudice refers to an undue tendency to suggest a decision on an improper basis and does not refer to merely being detrimental to one *253party’s case. Id. Further, evidence which is offered for one purpose need not be excluded merely because it is inadmissible for another. See Orlando v. Herco, Inc., 351 Pa.Superior Ct. 144, 505 A.2d 308 (1986).
The Pennsylvania Supreme Court has adopted the following provision of the Restatement (Second) of Torts § 323(a) (1965) as representing an accurate statement of the law. See Morena v. South Hills Health System, 501 Pa. 634, 462 A.2d 680 (1983).
§ 323. Negligent Performance of Undertaking to Render Services
One who undertakes, gratuitously or for consideration to render services to another which he should recognize as necessary for the protection of the other’s person or things, is subject to liability to the other for physical harm resulting from his failure to exercise reasonable care to perform his undertaking, if
(a) his failure to exercise care increases the risk of harm..
This provision, however, does not change the burden of a plaintiff to establish the elements of a negligence action or to invoke a duty where one does not exist. Morena; Boyce v. United States Steel Corp., 446 Pa. 226, 285 A.2d 459 (1971). Duty is predicated on the relationship existing between the parties at the relevant time and requires some degree of knowledge. See Morena.
In the matter sub judice, Mrs. Morrison had the burden of establishing that Ambulance Service owed a duty which required it to conform to a certain standard of conduct; Ambulance Service failed to conform to the standard required; Mr. Morrison’s death was caused by Ambulance Service’s conduct; and actual loss was suffered. See Morena; Berry v. Titus, 346 Pa.Superior Ct. 376, 499 A.2d 661 (1985), appeal dismissed, 517 Pa. 58, 534 A.2d 756 (1987). The testimony of the ambulance crew and the experts sufficiently established that Ambulance Service owed a duty to Mr. Morrison and that the standard of care required was that the service carefully *254and safely transport Mr. Morrison from the police station to Woodville. See also McCluskey v. United States, 583 F.Supp. 740 (S.D.N.Y.1984) (the standard of care required of an ambulance service is to safely deliver the patient into the custody of medical personnel competent to attend to the patient).
Regarding the proposition that Ambulance Service breached its duty to Mr. Morrison, the jury was presented with conflicting testimony concerning the degree of training required and how trained ambulance attendants would have operated in comparison with how the ambulance crew operated. The trial court is correct that since Ambulance Service’s expert testified that Mr. Morrison’s death was actually caused by his head injury and drowning, the disputed evidence is not relevant to causation. However, Mrs. Morrison was not seeking to establish that the ambulance crew could have rescued Mr. Morrison; her burden was to convince the jury that Ambulance Service’s failure to provide a trained ambulance crew was the proximate cause of Mr. Morrison’s death. Thus, the evidence in dispute was properly offered to prove the material fact that Ambulance Service failed to conform to local and national standards of conduct by not providing trained attendants.4
Finally, this is not a matter in which any prejudice to Ambulance Service’s case substantially outweighed the probative value of the disputed evidence. The trial court sufficiently cured the danger of unfair prejudice arising from confusion over whether the ambulance crew’s actions in leaving the scene of the accident, discussing the incident with Mr. Schleifer, and transporting another patient before going to the police station were the cause of death, by instructing the jury that if Mr. Morrison died as a result of his head injury, the ambulance crew’s failure to remain at the scene did not cause the death. See Whistler. Thus, the trial court erred by determin*255ing that a new trial was warranted merely because evidence was irrelevant to causation when that evidence was offered to prove a breach of a duty.
ORDER
AND NOW, this 29th day of May, 1992, the order of the Court of Common Pleas of Allegheny County is reversed.
. Mrs. Morrison initially filed this appeal in the Superior Court which granted Ambulance Service's motion to transfer the case to this Court by order dated September 19, 1991.
. Mrs. Morrison settled with OMH and Dr. Harika prior to trial and executed a joint tort-feasor release.
. The trial court also noted that it may have erred in charging the jury that Ambulance Service was acting as a common carrier but indicated that it would not decide that issue since it determined that a new trial was warranted based on "prejudicial error.” This Court notes that even if the characterization "common carrier” was error, it was harmless since the jury was properly instructed that an ambulance service which holds itself out to the public to accept anybody who wishes to use its service is traditionally viewed in the law as required to exercise the highest degree of care. See McNamara v. Schleifer Ambulance Service, Inc., 383 Pa.Superior Ct. 100, 556 A.2d 448 (1989).
. In addition, Ambulance Service's defense was that it did not breach its duty to Mr. Morrison, and the jury was presented with conflicting evidence regarding whether Mr. Morrison escaped through the front or rear door of the ambulance. Since the door from which he escaped is indicative of whether Ambulance Service was actually transporting Mr. Morrison in the manner it claims, the disputed evidence was properly admitted because it concerned the weight and credibility to be afforded the testimony of Ambulance Service’s witnesses.