We granted leave1 to appeal in this medical malpractice case to clarify the permissible scope of cross-examination of expert witnesses. The *472Court of Appeals reversed a jury verdict of no cause of action against defendants Dr. George P. Schanz and St. Mary’s Medical Center. The Court of Appeals held that the trial court abused its discretion by allowing cross-examination of plaintiff’s expert witness regarding that expert’s prior poor surgical results and prior medical malpractice claims.2 We reverse the decision of the Court of Appeals and reinstate the verdict of no cause of action for Dr. Schanz and St. Mary’s Medical Center.
i
FACTS
In August 1984, plaintiff Wade W. Wischmeyer injured his back in a fall. He consulted with several doctors over the following months.3 In January 1985, he consulted with defendant, a neurosurgeon in private practice in Saginaw with medical privileges at defendant hospital, St. Mary’s Medical Center. On May 29, 1985, Dr. Schanz admitted plaintiff to St. Mary’s Medical Center, and on the following day performed a L4-L5 diskectomy with a posterior lumbar interbody fusion (plif).4 During surgery, two St. Mary’s operat*473ing room technicians, Mark Nichols and Leah Lowery, assisted Dr. Schanz. Plaintiff alleges that soon after surgery his pain worsened and he experienced numbness in his right leg.
Plaintiff and his wife5 brought this action for medical malpractice in the Saginaw Circuit Court on May 29, • 1987, alleging that Dr. Schanz breached the standard of care in his treatment of plaintiff and that his injury would not have occurred absent some negligence on the part of Dr. Schanz.6 Against St. Mary’s, plaintiff raised two theories: first, that St. Mary’s failed to provide a qualified neurosurgeon to assist Dr. Schanz, and second, that Mark Nichols, the operating room technician, was negligent.
Each party relied on expert testimony to establish the appropriate standards of care. Defense counsel for Dr. Schanz called two medical experts who testified that there was no malpractice on the part of Dr. Schanz. Defense counsel for St. Mary’s Medical Center called one expert who testified that there was no negligence on the part of St. Mary’s employees.
The testimony of plaintiff’s only medical expert, Dr. Ronald J. Ignelzi, consumes two hundred pages of the record. On direct examination, Dr. Ignelzi outlined his credentials at length and explained that he had performed six to ten plifs, the type of surgery performed by Dr. Schanz on plaintiff, and that he had performed hundreds of other spinal surgeries. He explained in detail how various surgeries should be performed and concluded that Dr. Schanz performed the wrong procedure on plaintiff and had performed the procedure itself incorrectly. He stated that plaintiff’s symptoms "should *474not have occurred unless there was some negligence at the time of the procedure.”
On cross-examination, Dr. Ignelzi acknowledged that none of the plif surgeries he had performed had been successful because he had failed to relieve his patients’ pain. However, he denied remembering four other back surgeries that failed, including three failed laminectomies and one failed dorsal rhizotomy. Plaintiff’s counsel objected to the relevancy and prejudicial nature of raising non-PLiF surgeries, but was overruled. Dr. Ignelzi also denied that he had been the subject of a prior medical malpractice action.
The jury trial spanned two weeks. After deliberating for less than one hour, the jury returned a verdict of no cause of action with respect to both defendants. On appeal, plaintiff alleged that the trial court abused its discretion by permitting certain categories of cross-examination to proceed.
ii
CROSS-EXAMINATION
Rule 61 Iff)) of the Michigan Rules of Evidence states:
A witness may be cross-examined on any matter relevant to any issue in the case, including credibility. The judge may limit cross-examination with respect to matters not testified to on direct examination.
A broad range of evidence may be elicited on cross-examination for the purpose of discrediting a witness.7 The scope and duration of cross-examination is in the trial court’s sound discretion; we will *475not reverse absent a clear showing of abuse.8 The trial judge is charged with overseeing attacks on an expert’s credibility and insuring that
questions seeking to elicit evidence indicating bias, prejudice or interest and inconsistent testimony or statements are not unduly limited or improvidently extended. The trial judge must also be alert to questions which harass, intimidate or belittle a witness.[9]
However, when a case turns on the testimony of one expert compared with that of another, the credibility of each expert is relevant to the disposition of the case.10 The credibility of a medical expert, therefore, is relevant to the disposition of a medical malpractice case and evidence of an expert’s credibility generally is admissible unless its probative value is substantially outweighed by the danger of unfair prejudice.11
We must address two categories of testimony elicited by the defense during its cross-examination of Dr. Ignelzi: prior poor surgical results in non-PLiF back surgeries and prior claims of medical malpractice against him. These categories of evidence are addressed separately below._
*476A
PRIOR POOR NON-PLIF SURGICAL RESULTS
On cross-examination, defense counsel questioned Dr. Ignelzi regarding back surgeries the doctor had performed in the past. Plaintiff’s counsel entered an objection on unspecified grounds as the cross-examination regarding prior failed surgeries began, but. was overruled after a bench conference. The questioning by defense counsel proceeded as follows:
Q. Doctor, do you recall in 1980 performing surgery on a lady named Cynthia Hughes where you performed a laminectomy and the dura was ripped in a fashion and she was later discharged with the spinal fluid leaking?
A. No, I don’t.
Q. You don’t recall that?
A. No.
Q. Certainly something like that would be so horrible that you wouldn’t forget it, would you?
A. I don’t know what you mean by horrible, but I mean I don’t recall this case.
Q. Do you recall in May of 1979 performing surgery on an individual by the name of Rodgers who underwent a cervical laminectomy and developed a Brown-Sequard syndrome postoperatively?
Counsel for plaintiff objected to the relevancy and prejudicial effect of this questioning, but was overruled.
Q. Do you recall that, where you cut into the spinal cord?
A. What was that again?
Q. In May of 1979 do you recall performing a lamin--a cervical laminectomy on a gentleman *477by the name of Rodgers where he developed a Brown-Sequard syndrome postoperatively?
Q. Do you recall in January of 1979 surgery performed upon a Mr. Jack Rodgers who underwent a dorsal rhizotomy and wound up a paraplegic following the operation secondary to a hematoma?
A. No.
Q. You don’t recall that?
A. No.
Again, plaintiff’s counsel initiated a bench conference, followed by:
Q. Do you recall performing surgery on a Mr. Eric Woods in August of 1977 who underwent a laminectomy and wound up with a wound infection and postoperative epidural hematoma which resulted in paraplegia?
A. No.
Q. Do you remember that case of yours?
A. I don’t even know that that was a case of mine.
There is some confusion regarding whether plaintiff’s objections arose under MRE 608(b)12 or MRE 403. We find that both rules were correctly considered and decided by the trial court. The court permitted inquiry into prior non-PLiF surgeries because it felt that those surgeries were rele*478vant to the expert’s competency.13 We agree. Further, the court appropriately disallowed impeachment of Dr. Ignelzi on extrinsic matters under MRE 608(b), stating that defendant would be "stuck with” Dr. Ignelzi’s answer.14 At the conclusion of Dr. Ignelzi’s cross-examination, the trial court properly denied plaintiff’s motion for a mistrial, again holding that the cross-examination did not violate MRE 608(b).15
The Court of Appeals disagreed with the trial court’s rulings, citing Heshelman v Lombardi, 183 *479Mich App 72; 454 NW2d 603 (1990).16 However, Heshelman is not in conflict with the trial court’s ruling.17 In this case, Dr. Ignelzi testified that defendant should have undertaken a more conservative course of treatment, implying that a more conservative treatment would have prevented plaintiff’s injuries. Through this testimony, he placed his competency to condemn defendant in question. The cross-examination of Dr. Ignelzi regarding prior poor surgical results, therefore, did not raise extrinsic evidence prohibited by MRE 608. Because the competency of Dr. Ignelzi was properly before the court, evidence pertaining to his credibility was relevant.
It is intended that the Rules of Evidence promote the ascertainment of the truth.18 Where information is relevant and not unduly prejudicial, *480it would be unwise to apply MRE 608 so that the jury is deprived of information that would assist it in its task. We believe that this cross-examination was proper because during direct examination Dr. Ignelzi testified that he had performed hundreds of back surgeries, including plips, in order to establish his competency.19
The juxtaposition of Dr. Ignelzi’s testimony on direct examination and his conclusion that plaintiff’s condition could only result from some negligence during surgery rendered Dr. Ignelzi’s ability to perform such surgeries relevant. "Gaps or weaknesses in the witness’ expertise are a fit subject for cross-examination, and go to the weight of his testimony, not its admissibility.”20 Because expert testimony is admitted to assist the trier of fact, it was imperative that opposing counsel be afforded the opportunity to cross-examine Dr. Ignelzi to expose thé weaknesses in his knowledge, skill, experience, training, or education.21
We find further that the defendant’s line of questioning was not more prejudicial than probative. MRE 403 states in pertinent part, "[although relevant, evidence may be excluded if its probative value is substantially outweighed by the danger of unfair prejudice . . . .” There is no question that the line of questioning was potentially damaging *481to Dr. Ignelzi and therefore to plaintiff’s case.22 We continue to believe that "[witnesses should not be subjected to personal attacks and unsubstantiated insinuations.”23 Nor will we tolerate studied attempts to "prejudice the jury and divert the jurors’ attention from the merits of the case.”24 However, evidence does not present a danger of unfair prejudice unless it threatens the fundamental goals of MRE 401 and MRE 403: accuracy and fairness. Gold, Federal Rule of Evidence 403: Observations on the nature'of unfairly prejudicial evidence, 58 Wash L R 497 (1983). Our review of the record persuades us that there was no danger of unfair prejudice resulting from this line of questioning.
B
PRIOR MEDICAL MALPRACTICE CLAIMS
On cross-examination, the following exchange between defense counsel and Dr. Ignelzi occurred:
Q. Have you ever been a defendant in a malpractice suit, Doctor?
A. No.
Q. You haven’t?
A. No.
*482Q. I know I’ve got it here somewhere, Doctor. I’ve just got to take a moment to find it, if I may. The case of Kristeen [sic] . . .
Q. The Superior Court of the State of California for the County of San Diego in the case of Kristine Loreago and Doris Loreago plaintiffs, versus Ronald J. Ignelzi, do you recall that?
A. I really don’t remember any suit. I never testified in any depositions in this that I’m aware of.
Q. Breach of medical professional obligation?
A. I never saw that document. I don’t recall it.
While prior failed back surgeries are relevant to the competency of an expert witness whose expert opinion regarding defendant’s failure to perform the appropriate type of surgery at the correct level is premised on the number and variety of back surgeries the expert has performed, the mere fact that an expert may have been named in an unrelated medical malpractice action is not probative of his truthfulness under MRE 608 or relevant to his competency or knowledge.25
Thus, we find that it was improper for defendant to inquire into this medical malpractice action against Dr. Ignelzi. However, we find that the error was harmless. By the time that this question was raised, Dr. Ignelzi had been thoroughly discredited. He testified that plaintiff’s bad result from the plif procedure should not have occurred absent some negligence in the operating room. Then on cross-examination, he admitted that every time he had performed this surgery it resulted in failure. Consequently, his entire testimony was *483placed in jeopardy and any error in allowing this question about prior medical malpractice actions was harmless. Plaintiff’s counsel also rehabilitated Dr. Ignelzi on this issue on redirect examination when he elicited testimony to the effect that Dr. Ignelzi never went to trial in the malpractice case referred to by defendant.
Furthermore, because these categories of evidence are distinct, they required separate specific objections in order to preserve both for appeal. However, plaintiff did not object to this line of questioning, nor did he specifically raise the issue in his motion for mistrial. Plaintiff’s attempt to consolidate his appeal of this line of questioning with his appeal of the cross-examination regarding failed non-PLiF surgeries was improper. The Court of Appeals also failed to adequately distinguish between cross-examination regarding prior poor results in back surgeries and prior medical malpractice cases.
Under MRE 103, we review unpreserved error and reverse only if the substantial rights of a party are affected.26 Here no substantial rights of plaintiff were affected by this line of cross-examination.
in
st. mary’s medical center
Plaintiff alleged two theories of liability against St. Mary’s Medical Center: first, that the hospital was negligent because it did not provide a neuro*484surgeon to assist Dr. Schanz; and, second, under a res ipsa loquitur theory, that plaintiff would have suffered no injury absent negligence on the part of Mark Nichols. In a medical malpractice case, the plaintiff bears the burden of proving: (1) the applicable standard of care, (2) breach of that standard by defendant, (3) injury, and (4) proximate causation between the alleged breach and the injury.27 Failure to prove any one of these elements is fatal. Furthermore, evidence of a bad result alone is not sufficient to prevail under the theory of res ipsa loquitur.28 Where a plaintiff raises res ipsa loquitur in the medical malpractice context, we require that the plaintiff prove that the event (1) is of a kind that ordinarily does not occur in the absence of someone’s negligence, (2) is caused by an agency or instrumentality within the exclusive control of defendant, and (3) is not due to any voluntary action or contribution on the part of the plaintiff.29
Plaintiff in this case did not establish a prima facie case under either of his theories of recovery. During Dr. Ignelzi’s cross-examination by St. Mary’s, he specifically stated that the standard of care for plif surgery did not require a second doctor in assistance and that Mark Nichols had not violated any standard of care applicable to an operating room technician. In considering St. Mary’s motion for a directed verdict at the close of plaintiff’s case, the trial judge observed:
My recollection of the evidence is that there is no credible evidence as to the liability of the defendant hospital. However, I know that this is a drastic remedy, and I don’t want to trust my own *485recollection . . . because I know it’s a drastic remedy.
The Court of Appeals may overturn a jury verdict only if it is against the great weight of evidence.30 In its summary reversal of the trial court, the Court of Appeals failed to distinguish its reasoning for reversal of the verdict of no cause of action with respect to St. Mary’s Medical Center from its reversal of the verdict with respect to Dr. Schanz. The plaintiff’s theories against each defendant were separate and distinct, and it is apparent from the record that plaintiff failed to carry the burden of proof against St. Mary’s.
We reverse the decision of the Court of Appeals with regard to both St. Mary’s and Dr. Schanz and reinstate the trial court’s verdict of no cause of action.
Brickley, C.J., and Boyle and Riley, JJ., concurred with Weaver, J.447 Mich 1041 (1994).
203 Mich App 361; 512 NW2d 82 (1994).
After the fall, plaintiff consulted with Dr. Gruca, who treated plaintiff with medication on an out-patient basis. In November 1984, plaintiff consulted Dr. Jennings, whose video deposition was presented at trial. Dr. Jennings indicated to plaintiff that surgery would be required to alleviate plaintiff’s pain. For a second opinion, plaintiff consulted with Dr. Fields in January 1985. Dr. Fields, indicated that a type of fusion surgery would be necessary to relieve the pain, rather than a diskectomy or laminectomy, and he therefore referred plaintiff to defendant, Dr. Schanz who specialized in part in fusion surgeries.
A plif is a surgical procedure that stabilizes the spine by the insertion of bone plugs between vertebrae. Apparently, after disc has been removed by a standard diskectomy, a plif combines the medical procedure of a laminectomy, the cutting of a window in the bone, with the fusion of the bone plugs between vertebrae in vacated disc space.
Mrs. Wischmeyer claimed loss of consortium.
Plaintiff alleged that the fusion procedure was unnecessary and more invasive than necessary.
Wilson v Stilwill, 411 Mich 587, 599; 309 NW2d 898 (1981). See also 3A Wigmore, Evidence (Chadbourn rev), § 944, p 778.
Stilwill, n 7 supra at 599.
Id
Id.
MRE 401 states:
"Relevant evidence” means evidence having any tendency to make the existence of any fact that is of consequence to the determination of the action more probable or less probable than it would be without the evidence.
MRE 403 states in pertinent part:
Although relevant, evidence may be excluded if its probative value is substantially outweighed by the danger of unfair prejudice ....
MRE 608(b) states in pertinent part:
Specific instances of the conduct of a witness, for the purpose of attacking or supporting his credibility, other than conviction of crime as provided by Rule 609, may not be proved by extrinsic evidence. They may, however, in the discretion of the court, if probative of truthfulness or untruthfulness, be inquired into on cross-examination of the witness ....
When defense counsel asked if he could inquire into prior surgeries performed by Dr. Ignelzi, Judge Heathscott stated:
I would think that would go to his qualifications, and I would think so.
The court stated:
In reviewing the documents submitted by Mr. Fordney last night, I have also reviewed the Michigan Rules of Evidence, and I believe that Rule 608(b) is applicable to this situation. I am not going to allow impeachment of Dr. Ignelzi on a collateral matter, and I’m not going to allow extrinsic evidence. However, I do believe that Mr. Fordney will have the right to ask if the doctor has been terminated from hospital privileges anywhere, but you’re going to be stuck with the answer. I’m not going to allow you to go into any collateral matters, Mr. Fordney. I’m not going to allow you to use any of these documents, but you may ask if he’s been terminated from any privileges.
The extrinsic evidence and collateral matters referenced by the court involved certain federal court cases for which Dr. Ignelzi was under a gag order.
Judge Heathscott stated:
Mr. Maher, I’m not going to grant a mistrial .... Under 608(b), Mr. Fordney can cross examine about specific instances of conduct which he has done. He then must accept the answer of the doctor, and I believe that has been complied with. ... I understand your disagreeing with the suits being mentioned at all, but I want you specifically to address whether Mr. Fordney used extrinsic evidence to prove these specific instances of conduct in violation of my order.
The Court of Appeals stated in relevant part:
The trial court abused its discretion in allowing defense counsel to cross-examine plaintiffs’ expert witness, Dr. Ignelzi, regarding prior poor surgical results and prior medical malpractice claims. Heshelman v Lombardi, 183 Mich App 72; 454 NW2d 603 (1990). This line of questioning was not probative of truthfulness or untruthfulness, and constituted an improper means of impeaching the credibility of Dr. Ignelzi. Id. at 84-85. The cross-examination of plaintiffs’ expert on this basis cannot be considered harmless error. Heshelman, supra. The questions raised unproved accusations of acts' of malpractice in graphic detail and, we believe, thoroughly discredited Dr. Ignelzi before the jury. [203 Mich App 362.]
Heshelman v Lombardi, supra.
Heshelman addressed the admissibility of prior medical malpractice actions. As will be discussed in part ii(b), prior malpractice actions are not generally relevant to the competency of an expert.
MRE 102 states:
These rules are intended to secure fairness in administration, elimination of unjustifiable expense and delay, and promotion of growth and development of the law of evidence to the end that the truth may be ascertained and proceedings justly determined.
Plaintiff acknowledges that prior plif surgeries performed by Dr. Ignelzi are relevant.
People v Gambrell, 429 Mich 401, 408; 415 NW2d 202 (1987).
MRE 702 states:
If the court determines that recognized 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 thereto in the form of an opinion or otherwise.
The substance of the cross-examination in this case regarding prior poor surgical results is distinguishable from People v Chaplin, 412 Mich 219; 313 NW2d 899 (1981), cited by plaintiff. In People v Chaplin, this Court ruled that it was improper to impeach a witness on cross-examination by showing that she was a prostitute, because her moral character was not probative of her propensity for truthfulness. Insofar as the evidence of the witness’ prostitution was relevant to show bias, this Court held further that it should be excluded because the danger of unfair prejudice substantially outweighed its probative value.
Wayne Co Bd of Rd Comm’rs v GLS LeasCo, 394 Mich 126, 134; 229 NW2d 797 (1975) (an expert witness was repeatedly accused of lying and feigning ignorance of relevant information).
Kern v St Luke’s Hosp, 404 Mich 339, 354; 273 NW2d 75 (1978) (defense counsel repeatedly characterized the plaintiff’s expert testimony as "bought” and "collusive”).
See, e.g., Heshelman v Lombardi, supra; ECCO, Ltd v Balimoy Mfg Co, Inc, 179 Mich App 748; 446 NW2d 546 (1989). We need not decide whether evidence of prior medical malpractice would never be relevant.
MRE 103(d) states:
Nothing in this rule precludes taking notice of plain errors affecting substantial rights although they were not brought to the attention of the court.
MCL 600.2912a; MSA 27A.2912(1). See also Locke v Pachtman, 446 Mich 216, 222; 521 NW2d 786 (1994).
Locke, n 27 supra at 231.
Jones v Porretta, 428 Mich 132, 150-151; 405 NW2d 863 (1987).
Granstrom v Gray, 365 Mich 349; 112 NW2d 560 (1961); Newton v Huddle, 22 Mich App 314; 177 NW2d 222 (1970); Lake Oakland Heights Park Ass’n v Waterford Twp, 6 Mich App 29; 148 NW2d 248 (1967).