with whom VERTEFEUILLE, J., joins, concurring in part and dissenting in part. I concur with part I of the majority opinion and dissent from parts II and III of that opinion.
I
The majority concludes that the trial court improperly struck the defendant’s special defense asserting immunity from suit under the exclusivity provision of General Statutes § 31-284 (a)1 of the Workers’ Compensation Act (act). I respectfully disagree.
The defendant asserted the following special defense: “[The] [p]laintiff was injured on August 18, 1988, while *692[she]2 was participating in a residency program in internal medicine. Although [the] plaintiffs complaint alleges . . . that Yale University [the defendant] was operating this program, the program was in fact operated by [the] plaintiffs direct employer, Yale-New Haven Hospital [hospital], and by [the defendant. The] [p]laintiff s injury occurred in the course of [her] work in that residency program and at the same time arose out of and within the scope of [her] direct employment by [the] [h]ospital. [The] [h]ospital has paid, and will continue to pay, workers’ compensation benefits to [the] plaintiff and, therefore, it enjoys immunity from suit by reason of ... § 31-284 (a) of the . . . [a]ct, which provides that all rights and claims between employer and employees are abolished other than the rights and claims given by the . . . [a]ct. Although [the] plaintiff was not a direct employee of [the defendant], [her] claims against [the defendant] in this action are likewise barred by ... § 31-284 (a) because at the time of [her] injury the residency program in internal medicine was, and had been for many years, a joint adventure, venture, enterprise or undertaking between [the] [h]ospital and [the defendant] in which they each had a voice and in which they combined their respective property, money, efforts, skill and knowledge in the common purpose of operating the internal medicine residency program to educate and train participants such as the plaintiff.”
The plaintiff moved to strike the defendant’s special defense on the ground that “it [was] insufficient as a matter of law because: [(1) the] [plaintiff’s claims against [the defendant] are not barred by reason of the exclusivity provision of ... § 31-284 (a); [(2) the defendant] is not an ‘employer’ as that term has been *693defined by . . . General Statutes § 31-275 (10);3 [(3) the defendant] is not a joint venturer; [and (4) the plaintiff] was not employed within the scope of the operation of the residency program.”
The trial court noted that “[t]he [defendant] has acknowledged that it was not [the plaintiffs] direct employer but claims that it is entitled to the same immunity by virtue of its having engaged in a joint venture, enterprise or undertaking with the [hjospital . . . .” The trial court then found that, as a matter of law, joint ventures are not included within the definition of “employer” under the act; see General Statutes § 31-275 (10); and that, in any case, not-for-profit entities cannot form a joint venture. The trial court observed that “[t]he [defendant] seeks the immunity offered by the workers’ compensation statutes without having undertaken any of the obligations that would entitle it to such immunity. It has alleged in its . . . [s]peciai [d]efense that the scope, or common purpose, of the operation of the residency program was to educate and train students participating in the program. [The plaintiffs] only participation in the residency program at the time of [her] injury was as a student. [She] was not, therefore, involved in the operation of the program to educate and train. [The plaintiff] was the object of the program, not its operator, and the [the defendant] was [her] teacher, not [her] employer. [The plaintiffs] only employment was by the [hjospital for the purpose of treating its patients. [Her] injury did not occur while *694performing the business of the affiliation between the [defendant] and the [h]ospital, and, the [defendant] is therefore not entitled to immunity from suit under . . . § 31-284.”
“A motion to strike challenges the legal sufficiency of a pleading. . . . [I]t admits all facts well pleaded; it does not admit legal conclusions or the truth or accuracy of opinions stated in the pleadings.” (Citations omitted.) Mingachos v. CBS, Inc., 196 Conn. 91, 108, 491 A.2d 368 (1985). A motion to strike “is to be tested by the allegations of the pleading [that is the subject of the motion to strike], which cannot be enlarged by the assumption of any fact not therein alleged. Blanchard v. Nichols, 135 Conn. 391, 392, 64 A.2d 878 [1949]; Santoro v. Kleinberger, 115 Conn. 631, 633, 163 A. 107 [1932]. Wexler Construction Co. v. Housing Authority, 144 Conn. 187, 194, 128 A.2d 540 (1956).” (Internal quotation marks omitted.) Alarm Applications Co. v. Simsbury Volunteer Fire Co., 179 Conn. 541, 549-50, 427 A.2d 822 (1980).
I recognize that the “modem trend ... is to construe pleadings broadly and realistically, rather than narrowly and technically.” (Internal quotation marks omitted.) Parsons v. United Technologies Corp., 243 Conn. 66, 83, 700 A.2d 655 (1997). Even under this relatively generous standard, however, I would affirm the trial court’s granting of the motion to strike. The defendant alleged in its special defense that the plaintiffs injury “arose out of and within the scope of [her] direct employment by [the] [h]ospital.” It further alleged that the “plaintiff was not a direct employee of [the defendant] . ...” I would affirm the trial court’s granting of the motion to strike because, not only did the defendant fail to allege that it was the plaintiffs employer, but it specifically alleged that it was not the plaintiffs “direct employer,” a term not used in the act. Section *695§ 31-284 (a)4 provides immunity only to employers. The allegation that the defendant was engaged in a joint venture with the plaintiffs employer is not, by itself, sufficient to confer employer status on the defendant. Neither is the defendant’s allegation that the plaintiffs injury occurred during the course of her “work” in the residency program, which was operated, in part, by the defendant, sufficient for such a purpose. The special defense contains no allegation that the defendant had the “right to control” the plaintiff, which the majority recognizes as the test for an employer-employee relationship.5 Thus, the defendant did not allege any of the elements required to claim immunity under the act. Furthermore, the necessary elements of the immunity defense are not necessarily implied by any of the allegations in the defendant’s special defense. See Clohessy v. Bachelor, 237 Conn. 31, 33 n.4, 675 A.2d 852 (1996) (“[w]hat is necessarily implied [in an allegation] need not be expressly alleged”). Therefore, the defendant’s special defense is legally insufficient and it was properly struck by the trial court.6
I am also not persuaded by the defendant’s arguments at trial and during oral argument that its special defense contains a pleading in the alternative, and that the defendant’s allegation that it was not the plaintiffs direct employer, therefore, should not be construed as an admission. The defendant claimed that its alternative *696pleadings were: (1) that neither the plaintiff nor Alison Heald, a third year resident who had supervised the plaintiff, was an employee or an agent of the defendant; or (2) if Heald were found to be the defendant’s agent, then the plaintiff must be the defendant’s employee for the purposes of the act.
I am not persuaded by this argument because nothing about the defendant’s special defense suggests that it is a pleading in the alternative. Furthermore, pleadings in the alternative must be “based on genuine doubt . . . .” (Internal quotation marks omitted.) DeJesus v. Craftsman Machinery Co., 16 Conn. App. 558, 567, 548 A.2d 736 (1988). “The pleader states the facts in the alternative because he [or she] is uncertain as to the true facts.” (Internal quotation marks omitted.) Id., 567-68. Only “[alternative factfual] allegations made in good faith and based on genuine doubt are not admissions against interest so as to be admissible in evidence against the pleader.” (Internal quotation marks omitted.) Id., 567. Nowhere in its pleadings did the defendant indicate that it did not know whether the plaintiff was its employee.
Furthermore, at trial, Edwin C. Cadman, senior vice president of medical affairs for the hospital, professor of medicine at Yale University School of Medicine, chairman of the school’s department of medicine and the person ultimately responsible for administration of the residency program when the plaintiff was accepted into it, specifically testified in response to questioning by the defendant that the plaintiff was not an employee of the defendant doing business as Yale University School of Medicine.7 Finally, the defendant argued dur*697ing closing arguments that the plaintiff “was an employee of [the] [h]ospital, not an employee of [the defendant]. And there is no dispute about that.” Yet the defendant argues that a new trial is required so that it can attempt to prove that the plaintiff was its employee. I cannot agree.
Moreover, I am not persuaded by the defendant’s argument that it is somehow unfair to deprive the defendant of the immunity defense on the ground that the defendant had not alleged facts implying that it was the plaintiffs employer while simultaneously allowing the plaintiff to prove an agency relationship between Heald and the defendant for purposes of establishing vicarious liability. I recognize that, in Connecticut, the “right to control” test historically has determined the relationship between a worker and a putative employer. I believe, however, that this court should recognize that, while it is necessary to find a “right to control” in order to establish an employer-employee relationship, such a finding should not always be sufficient to establish such a relationship in the context of workers’ compensation claims involving issues of joint employment.
In Hanson v. Transportation General, Inc., 245 Conn. 613, 716 A.2d 857 (1998), on which the majority relies to support its conclusion that employer status for purposes of workers’ compensation claims is a question of the right to control, this court recognized that *698“the right to control test, in its present form, was embedded into the act by early cases relying on similar rules in [vicarious liability] cases.” Id., 617 n.5. Larsons’ treatise, however, indicates that the concept of employee, for purposes of workers’ compensation law, may be narrower than the common-law concept of servant, which turns on the right to control. 3 A. Larson & L. Larson, Workers’ Compensation Law (1999) p. 64-1. The treatise states that “[t]he end product of a vicarious liability case [in which a master-servant relationship must be established] is not an adjustment of rights between employer and employee on the strength of their mutual arrangement, but a unilateral liability of the master to a stranger. The sole concern of the vicarious liability rule, then, is with the master: Did he or she accept and control the service that led to the stranger’s injury?
“Compensation law, however, is a mutual arrangement between the employer and employee under which both give up and gain certain things. Since the rights to be adjusted are reciprocal rights between employer and employee, it is not only logical but mandatory to resort to the agreement between them to discover their relationship. To thrust upon a worker an employee status to which he or she has never consented would not ordinarily harm him or her in a vicarious liability suit by a stranger against his employer, but it might well deprive him or her of valuable rights under the compensation act, notably the right to sue his or her own employer for common-law damages.” 3 id., § 64.01, pp. 64-2 through 64-3.8 Therefore, I do not believe that a *699determination that there was a master-servant relationship between the defendant and Heald, based on the defendant’s “right to control,” necessarily, or even presumptively, should be conclusive as to whether Heald was the defendant’s employee. Much less should such a determination be conclusive as to whether the plaintiff was the defendant’s employee.
II
The majority has concluded that the plaintiffs claim is not an educational malpractice claim. The majority, instead, has concluded, and I agree, that this claim is a simple tort claim governed by Kirchner v. Yale University, 150 Conn. 623, 192 A.2d 641 (1963). I also agree with the majority that the fact that this is a simple negligence claim does not necessarily mean that the plaintiff is not required to present expert testimony. For the reasons that follow, however, I do not agree with the majority that the trial court’s instruction to the jury that it may, rather than must only, consider expert testimony was harmful error.
It is well established that, if “the determination of the standard of care requires knowledge that is beyond *700the experience of an ordinary fact finder, expert testimony will be required.” Santopietro v. New Haven, 239 Conn. 207, 226, 682 A.2d 106 (1996). In Kirchner, because the proper method of operating a jointer, a device used to plane wood; Kirchner v. Yale University, supra, 150 Conn. 625; was not within the knowledge or experience of the ordinary fact finder, the plaintiff presented expert testimony “that a push block rather than a push stick was the proper and reasonably safe device to use in operating the jointer.” Id., 627. The plaintiff then presented factual testimony that “the plaintiff did not see, nor know of, a push block or any device other than the push stick . . . that no push block was made available for use by the plaintiff, and that there were no regulations, warnings, or instructions posted in the shop, or otherwise communicated to the plaintiff, regarding the safe and proper operation of the jointer or the dangers incident to the use of a push stick in its operation.” Id. Thus, the plaintiff in Kirchner presented expert testimony on the method of operating a jointer, which required special knowledge, and factual testimony on whether the plaintiff was properly instructed in that method or warned of the dangers of operating the machine in any other method, which was within the knowledge of laypersons. Id. This court concluded that, on the evidence presented, “a jury could well have concluded that in the exercise of reasonable care the defendants should have anticipated that unless they made a push block available and gave some warning or instruction to the plaintiff that he should use a push block rather than a push stick in the operation of the jointer, harm of the general nature of that which actually occurred was likely to result, and that the defendants’ failure in each respect constituted negligence . . . .” Id., 627-28.
In this case, following the Kirchner paradigm, the issue of whether the defendant breached the standard *701of care can be divided into the following subissues: (1) what was the proper method for performing an arterial line insertion; and (2) did the defendant properly instruct the plaintiff in that method?
Determination of the first subissue clearly requires the fact finder to have specialized knowledge, and the plaintiff, therefore, is required to present expert testimony on that subissue. With the exception of Heald, whose deposition testimony was admitted at trial, all of the experts who testified at trial agreed that the proper method for arterial line insertion requires removal of the needle from the operative field immediately upon withdrawing it from the catheter.9 Heald *702testified at her deposition that she found the method the plaintiff used in reenacting the injury, during which she kept the needle in her left hand after withdrawing it from the catheter, to be acceptable. The defendant, however, did not adopt the position taken by Heald. Rather, during its closing arguments to the jury, the defendant argued that the plaintiff “did this procedure perfectly from beginning to end, except for one thing: she violated the most basic principle — when you take the needle out and you are through with that needle in the procedure, get rid of it. She didn’t do that. And that’s why she stuck herself. And both [doctors Mary M.] Cooke and ... [E. Clinton] Lawrence acknowledged that the reason she stuck herself was because she violated this basic principle: that she did not remove the needle from the field as soon as she was through using it.”
Thus, there clearly was no dispute between the parties as to the first subissue concerning the standard of care. Both parties adopted the expert testimony that the method of arterial line insertion that the plaintiff used was improper and that the proper method required removal of the needle from the operative field as soon as it was no longer needed. Therefore, even though I *703would find that the jury charge10 in this case was improper as to the first subissue because it implied a right of the jury to consult its own judgment and common sense rather than expert opinion, the impropriety was harmless. To conclude otherwise, this court must assume that the jury rejected the undisputed expert testimony that the technique the plaintiff used in inserting the arterial line was improper, and that the jury then came to the same conclusion relying only on its own common sense and experience. I decline to make that assumption.
With regal’d to the second subissue, namely, whether the defendant properly instructed the plaintiff in the proper method of performing an arterial line insertion so as to avoid injury, I would conclude that no specialized knowledge is required to find a breach of this duty.
“While the standard of care, skill and diligence is a matter of expert opinion and knowledge, the determination of the facts concerning the conduct under consideration is always for the jury.” Snyder v. Pantaleo, 143 Conn. 290, 295, 122 A.2d 21 (1956). A plaintiffs expert witnesses need not specifically express an opinion that the defendant breached the standard of care in order for a plaintiff to prevail. See Santopietro v. New Haven, supra, 239 Conn. 229. Rather, the plaintiff need only produce “sufficient expert testimony to permit the jury reasonably to infer, on the basis of its findings of fact, that the defendant breached the standard of care.” Id., 229-30. Breach of the standard of care may be proved “through the testimony of the defendant.” Id., 229.
*704In this case, both the plaintiff and the defendant agreed with the expert testimony that the proper method of performing an arterial line insertion required removal of the needle from the operative field immediately upon withdrawing it from the catheter. The plaintiff also presented factual testimony that the defendant never specifically had instructed her on how to control the flow of blood from the artery after insertion of the catheter. She presented factual testimony that, while performing the procedure under Heaid’s supervision, she kept the needle in her hand after withdrawing it from the catheter under the mistaken assumption that she could reinsert the needle. Furthermore, on one occasion, the plaintiff actually reinserted it. There was no testimony that Heald ever had instructed the plaintiff that her technique was improper or specifically had told her to remove the needle from the operative field immediately upon withdrawing it from the catheter. Rather, the plaintiff testified that Heald said nothing to her after observing her improper technique. In addition, Heald testified that she believed that the technique the plaintiff used during the procedure when she was injured was acceptable, and that it was acceptable to reinsert the needle into the catheter. The defendant did not dispute the factual testimony presented by the plaintiff, but argued, instead, that the plaintiff, by virtue of her prior medical school training, should have known, without further instruction, the “basic principle” that all needles should be removed from the operative field immediately after use, and that her injury, therefore, was a result of her own negligence.
In my opinion, based on this evidence, “an ordinary fact finder”; Santopietro v. New Haven, supra, 239 Conn. 226; could reasonably infer; see id., 229; based on its own judgment and experience, that the defendant had breached the standard of care by failing to instruct and warn the plaintiff in the conduct of this dangerous *705procedure. See Kirchner v. Yale University, supra, 150 Conn. 627 (university has duty to exercise reasonable care “to instruct and warn students in the safe and proper operation of the machines provided for their use”). In Kirchner, the plaintiff presented no expert testimony that the method of instruction the defendants used was improper, but, rather, presented factual testimony that there had been no instruction in the proper technique. See id., 627-28. The court found that, based on this evidence, a jury reasonably could have concluded that the defendants had breached their duty. Id., 627.
Similarly, in this case, I do not believe that the plaintiff was required to present an expert opinion that the defendant’s methods of instruction were improper. Rather, I would conclude that the factual testimony that the plaintiff presented, including Heald’s deposition testimony that she found the plaintiffs technique to be acceptable and the plaintiffs uncontradicted testimony that she had received no instruction that her technique was improper, together with the expert, testimony that the plaintiffs technique was improper and that first year residents must be specifically instructed to remove the needle from the operative field while performing an arterial line insertion,11 was sufficient for the jury reasonably to infer that there had been no instruction in the proper technique for arterial line insertions, that the standard of care, therefore, had been breached, and that the defendant “should have anticipated . . . harm of the general nature of that which actually occurred was likely to result . . . .” Id., 627-28; see also Santo-pietro v. New Haven, supra, 239 Conn. 229-30 (plaintiff need only produce “sufficient expert testimony to permit the jury reasonably to infer, on the basis of its *706findings of fact, that [the defendant] breached the standard of care”). Therefore, I disagree with the holding of the majority that the trial court’s jury instruction that the jury may consider expert testimony on whether the standard of care had been breached was improper as to the second subissue.
Furthermore, even if the jury were required to consider only expert testimony on the issue of whether the defendant had breached the standard of care, the plaintiff presented ample, undisputed expert testimony to support the jury’s verdict on that issue. Lawrence, a physician and an expert in arterial line insertion, testified that the technique the plaintiff had used under Heald’s supervision was not acceptable. He testified that it would be a breach of the standard of care to instruct a first year resident to hold the needle “outside and in close proximity to the catheter,” and that a first year resident must be specifically trained to remove the needle from the operative field. Lawrence also testified that it would be a breach of the standard of care to order a first year resident to insert an arterial line without supervision when he or she has performed only one prior successful arterial line insertion.
Louise Lucianin Fisher, a physician and the director of the hospital’s internal medicine residency program, testified that the technique that the plaintiff used under Heald’s supervision, and without correction by Heald, was not acceptable and should not have been used at the hospital in 1988. She also testified that, if a person believed that reinsertion of the needle into the catheter was acceptable, then it would not be a violation of universal precautions; see footnote 9 of this dissenting opinion; for that person to keep the needle in the operative field after withdrawing it from the catheter, because there would be a further use for it.
Cooke, a physician and an expert in the training of medical residents, testified that for Heald to have *707observed the plaintiff while the plaintiff kept the needle in the field and then reinserted it into the catheter, and then to have failed to correct that technique, was “completely inadequate supervision . . . .”
Again, I find it implausible that the jury rejected all of this testimony that the defendant had failed to instruct the plaintiff in the proper technique for arterial line insertions, and then came to the same conclusion based on only its own judgment and experience. Therefore, even if the charge were improper, which I do not believe, it was harmless.
The majority holds that there was no expert testimony to support many of the allegations in the plaintiffs complaint. I do not agree.
The general theory under which the plaintiff proceeded in this case was that the defendant failed to train, supervise and evaluate the plaintiff properly and adequately, which resulted in her serious injury. This is the same general theory that this court recognized in Kirchner v. Yale University, supra, 150 Conn. 623. I would find that each of the specific factual allegations in the plaintiffs complaint is colorable under the theory of recovery recognized by this court in Kirchner. I recognize that some of the plaintiffs allegations are somewhat vague. For instance, the plaintiff alleged that the defendant “failed to provide a safe work environment . . . .” Based on the evidence presented, however, a reasonable jury could have found that the plaintiff failed to provide a safe work environment by failing to instruct the plaintiff in a proper and safe technique for performing arterial line insertions. In my opinion, there was sufficient evidence of each of the factual allegations in the plaintiffs complaint for the jury to have found that the defendant had breached the standard of care.
Accordingly, I concur in part and dissent in part.
Although General Statutes § 31-284a has been amended numerous times since the plaintiffs date of injury in 1988, those amendments are not relevant to this appeal. For convenience, references to § 31-284a. throughout this opinion are to the current revision.
The pleadings originally used masculine pronouns to refer to the plaintiff.
General Statutes § 31-275 (10) provides in relevant part: “ ‘Employer’ means any person, corporation, limited liability company, firm, partnership, voluntary association, joint stock association, the state and any public corporation within the state using the services of one or more employees for pay, or the legal representative of such employer . . .
Although § 31 -275 (10) has been amended since the plaintiffs date of injury in 1988, those amendments are not relevant to this appeal. For convenience, references to § 31-275 (10) throughout this opinion are to the current, revision.
General Statutes § 31-284 (a) provides in relevant part: “An employer who complies with the requirements of subsection (b) of this section shall not be liable for any action for damages on account of personal injury sustained by an employee arising out of and in the course of his employment or on account of death resulting from personal injury so sustained . . .
As I indicate later in this dissenting opinion, I believe that this court should reexamine its use of the “right to control” test as the determinative test for employee-employer relationships in the context of workers’ compensation claims involving issues of joint employment.
The majority analyzes the special defense as if it alleged that the plaintiff was employed by the alleged joint venture. I do not read the special defense as containing such an allegation.
The transcript reads in relevant part:
“[Defendant’s Counsel]: By whom was [the plaintiff] employed when she began her residency program?
“[Cadman]: Yale-New Haven Hospital.
“Q. Let me show you defendant’s exhibit 2, which has now been admitted as a full exhibit, and ask you whether you recognize that as [the plaintiffs] employment agreement with Yale-New Haven Hospital.
*697“A. Yes, it is.
“Q. Thank you. And was [the plaintiff], to your knowledge, an employee of Yale University or Yale Medical School?
“A. No, she was not.
“Q. And it was Yale-New Haven Hospital and not Yale University or Yale Medical School who paid the salary and the fringe benefits referred to here?
“A. Yes.
“Q. And is it 1 rue . . . that all of the participants in the residency program, the residents, first year, second year, third year’, are employed by Yale-New Haven Hospital and not Yale Medical School?
“A. Correct."
This portion of Larsons’ treatise was relied on by the Supreme Court of Alabama in Ex parte Stewart, 518 So. 2d 118 (Ala. 1987). In that case, the petitioner, a resident manager of an apartment complex brought a workers’ compensation claim against the rental and management agent for injuries incurred during a fire. Id., 119. The trial court ruled that, because the owners of the apartment complex had retained a right of control over the petitioner’s work, she was an employee of the owners, not of the rental and management agent. See generally Stewart v. Carter Realty Co., 518 So. 2d 117 (Ala. Civ. App. 1986). The Alabama Supreme Court concluded that “[a] finding of *699control in one putative employer does not absolve the other putative employer of compensation liability, where there is evidence of joint or concurrent control.” Ex parte Stewart, supra, 121. The Alabama Supreme Court also concluded, however, that “the finder of fact should concentrate, not solely on control, but also on additional indicia of the employment relationship in determining an employee’s status.
* ** %
“In spite of the appearance of some possible ‘control’ in the owners, il' no contractual relationship existed between the owners and [the petitioner], then [she] was not their employee . . . .” (Citations omitted.) Id. I find this approach, which focuses on the contractual intentions of the parties, to be more reasonable than the strict “right to control” test employed by this court. Following the approach taken by the Alabama Supreme Court in Stewart in this case, Cadman’s testimony at trial that the plaintiffs employment agreement was exclusively with the hospital; see footnote 7 of this dissenting opinion; would strongly suggest that the plaintiff was not the defendant’s employee.
E. Clinton Lawrence, a physician who testified on behalf of the plaintiff as an expert in arterial line insertion techniques, testified that it is inherently dangerous to keep the needle in the operative field after withdrawing it from the catheter, and that that is not an acceptable method. On cross-examination, counsel for the defendant asked Lawrence: “And would you agree . . . that it is a basic principle that applies in every one of the literally hundreds of procedures in which health care professionals use needles, it’s a basic principle that when you finish using the needle in the procedure you get rid of it?” Lawrence replied: “That is a basic principle, yes.”
Louise Lucianin Fisher, a physician and the director of the internal medicine residency program at the hospital, testified that residents were given 1 raining in “universal precaul ions, ” which was designed to educate residents about protecting against exposure to blood-borne pathogens. Fisher testified that, pursuant to these universal precautions, it is improper to keep the needle in the operative field in order to reinsert the needle into the catheter. Fisher clarified her testimony on cross-examination, stating that universal precautions require needles to be taken out of the operative field as soon as they are no longer needed. Fisher further testified that, if aperson believed that reinsertion of the stylet into the catheter after withdrawal was proper, then the needle would still be needed, and failing to take it out of the operative field would not violate universal precautions.
Mary M. Cooke, a physician who testified on behalf of the plaintiff as an expert in the training of medical residents, testified that the needle should be taken out of the operative field after withdrawing it from the catheter, as there is no use for it after that point. Cooke testified that the needle should never be reinserted because of the danger of cutting the catheter with the tip of the needle. Cooke further testified that the procedure is “very difficult,” and that a new intern would not be expected to be competent at performing the procedure, even if the intern had extensive experience with other medical procedures involving the use of needles. Cooke further testi-*702fled that Heald “was clearly not teaching [the procedure] properly.”
The plaintiff testified that, when Heald demonstrated the procedure to her, Heald continued to hold the needle in her right hand after withdrawing it from the catheter. The plaintiff also testified that, when she performed the procedure under Heald’s supervision, she reinserted the needle into the catheter after withdrawing it in an attempt to insert the catheter into the artery, and that Heald did not correct her method. The plaintiff testified further that, when she performed the procedure on another patient under Heald’s supervision, she continued to hold the needle in her hand so that she could use it to reposition the catheter if required, and that Heald did not correct her. Finally, the plaintiff testified that, when she performed the procedure on the patient infected with the human immunodeficiency virus, she kept the needle in her left hand after withdrawing it from the catheter, and that she pricked her right thumb while trying to use her thumb to stem the flow of blood from the catheter.
The trial court instructed the jury as follows: “Since the intricacies of the operation of medical residency programs are normally outside the knowledge of most laypersons, each side has questioned witnesses who have an expertise in this area. On the issue of any duty owed by the defendant to the plaintiff, you may consider the evidence of the medical experts on what standard of care was appropriate in 1988 in the circumstances in which the plaintiff and the defendant found themselves.”
Lawrence, a physician and an expert in arterial line insertion, testified that first year residents must be specifically instructed to remove the needle from the operative field.