OPINION
POWERS, Justice.
Tracy Hinton sued the University of Texas at Austin and the Board of Regents of the University of Texas System to recover damages for injuries allegedly caused by their negligence. She recovered judgment on the jury verdict as provided in the Texas Tort Claims Act.
The University and the Board of Regents appeal.
Hinton appeals from that part of the trial-court judgment that denies her claim for prejudgment interest. We will affirm the judgment.
THE CONTROVERSY
In 1978 Hinton was an undergraduate student at the University of Texas at Austin. As she studied in the Academic Center on the University campus, a plastic grate from a light fixture fell about five feet and struck Hinton in the head. She received emergency treatment for cuts and bruises,
but did not require hospitalization or sutures.
Hinton sued the University and Board of Regents, alleging their negligent failure to secure the plastic grate proximately caused her physical and psychological injury. She complained in particular of continuous headaches, a diminished ability to concentrate, changes in personality, pain and suffering, and other problems.
The jury found that $800,000 would reasonably compensate Hinton for past and future injuries proximately caused by the negligence of the University. This sum, along with $394,847.33 in prejudgment interest, exceeded the $100,000 recovery limit imposed by the Texas Tort Claims Act.
The Defendants appeal from the resulting judgment awarding Hinton $100,000, court costs, and postjudgment interest. In a cross-appeal, Hinton complains the trial court erred in denying her claim for prejudgment interest.
THE PARTIES
The first jury question inquired concerning the negligence of “the Defendant.” The third question asked whether “the University of Texas” was negligent. In their first two points of error, the University and the Board of Regents allege the trial court erred in rendering a joint and several judgment against the Defendants based on these findings. The Defendants argue that the University and the Board of Regents are separate legal entities; therefore, to impose liability on both, Hinton had to obtain jury findings that each entity was negligent, and that the negligence of each was a proximate cause of her injury. The questions, as submitted, treated the University and Board of Regents as one entity.
We may not reverse the trial-court judgment on the ground that Hinton failed to obtain a separate set of negligence findings as to each Defendant. The record reveals that the parties uniformly pleaded the case just as the charge was submitted to the jury — that “the University of Texas” and “Defendant” were terms that encompassed both defendants. The jury finding of negligence on the part of the “Defendant” and “the University of Texas” necessarily encompassed both Defendants in their own usage of the term.
Cf. Walsh v. University of Texas,
169 S.W.2d 993, 993 (Tex.Civ.App.1942, writ ref'd n.r.e.) (stating that the University and the Board of Regents are institutions of the state, and neither has any existence independent of the state; therefore, any suit against either is in reality a suit against the state).
If either contended for a misjoinder of parties, the obligation lay upon them to raise and present the contention before the case was submitted to the jury; failing that, any complaint was waived. Tex. R.Civ.P.Ann. 41 (Supp.1991);
see Barton v. Farmers’ State Bank,
276 S.W. 177, 179 (Tex.1925) (An objection to misjoinder of parties “should be pleaded in limine ... or at the first reasonable opportunity in any event [or] the right to make it is waived.”);
Dairyland County Mut. Ins. Co. v. Estate of Basnight,
557 S.W.2d 597, 602 (Tex.Civ.App.1977, writ ref’d n.r.e.) (where plaintiff sued the “estate” of the deceased instead of the administrator of the estate, the latter was bound by the judgment owing to his active participation in the ease, notwithstanding that the “estate” of a deceased person is not a legal entity). Neither Defendant assailed its joinder or that of the other throughout the course of trial; it is a matter raised for the first time on appeal. We hold the Defendants waived the complaint.
DISCUSSION OF INSURANCE
During the voir dire examination by Hinton’s attorney, a panel member asked about Hinton’s insurance coverage. The trial court instructed the panel that it was not to consider insurance for any purpose during the trial. Nevertheless, some members of the panel expressed concern that Hinton might be “double-dipping,” that is,
receiving payment from her insurance company while attempting to recover from the Defendants as well. Hinton’s attorney informed the panel that Hinton had insurance coverage at the time of the accident, but that she would have to repay the insurance company for any amounts recovered from the Defendants. Arguing that this left the impression that Hinton owed the insurance company money, the Defendants objected and moved for a mistrial. The trial judge overruled the Defendants’ motion for mistrial. In their third, fourth and fifth points of error, the Defendants complain the trial court erred by allowing Hinton’s attorney to discuss Hinton’s insurance coverage during the voir dire examination.
We do not agree that the trial court erred by allowing Hinton’s counsel to state the effect of insurance subrogation rights. It is true that a plaintiff may not inform the jury that the defendant has insurance coverage, and a defendant may not inform the jury that a plaintiff has insurance protection.
Ford v. Carpenter,
147 Tex. 447, 216 S.W.2d 558, 559 (Tex.1949). We have found no authority, however, for the proposition that a party may not inform the jury of his or her own insurance coverage. We hold the trial court did not abuse its discretion by allowing Hinton’s attorney to inform the panel of the relative rights of Hinton and her insurance company.
Even if the trial court erred, we do not see how the Defendants were harmed. The mention of insurance before a jury is not always reversible error.
Dennis v. Hulse,
362 S.W.2d 308, 309 (Tex.1962). The party appealing must show: (1) that the reference to insurance probably caused the rendition of an improper judgment in the case; and (2) that the probability that the mention of insurance caused harm exceeds the probability that the verdict was grounded on proper proceedings and evidence.
Id.; cf. Reviea v. Marine Drilling Co.,
800 S.W.2d 252, 256 (Tex.App.1990, writ denied) (holding that no harm was shown when a prospective juror spontaneously brought up the issue of a party’s insurance coverage). The logic behind the rule excluding evidence of liability insurance is that a jury is more likely to find against a party who is insured.
Pride Transp. Co. v. Hughes,
591 S.W.2d 631, 634 (Tex.Civ.App.1979, writ ref’d n.r.e.). It would appear to work to the plaintiff’s disadvantage to inform the jury that he or she had health and accident insurance coverage at the time of the incident because jury members would expect that the plaintiff had been adequately compensated.
The Defendants argue that the large amount of damages awarded by the jury demonstrates the harm required by Tex. R.App.P.Ann. 81(b)(1) (Pamph.1991). We disagree. First, the trial court instructed the jury panel not to consider the existence of insurance for any reason in their deliberations. We must presume the jury obeyed the instruction of the trial court and disregarded the existence of insurance.
Duncan v. Smith,
393 S.W.2d 798, 805 (Tex.1965);
Hughes,
591 S.W.2d at 634. Second, the record as a whole must show harm to the complaining party.
Dennis,
362 S.W.2d at 310. From our view of the evidence, we cannot say the damages awarded in this case were excessive in light of Hinton’s evidence. Finally, the Defendants’ argument stands the exclusion-of-insurance rule on its head. Courts exclude evidence of the existence of insurance because it is not relevant to the issue of liability and may improperly influence the jury.
Id.
In contrast, Hinton’s attorney discussed insurance in order to correct the panel members’ erroneous and prejudicial impression that Hinton was seeking a double recovery. We therefore do not believe that the size of the damage award alone indicates harm. We overrule points of error three, four and five.
EXPERT TESTIMONY
The Defendants complain the trial court erred by excluding the testimony of their expert witness, Dr. Tindall. The trial court imposed this sanction against the Defendants because they failed to supplement their answers to discovery requests.
See
Tex.R.Civ.P.Ann. 215(5) (Supp.1991).
The rules of procedure impose certain requirements on a party who plans to call an expert witness:
If the party expects to call an expert witness when the identity or the subject matter of such expert witness’ testimony has not been previously disclosed in response to an appropriate inquiry directly addressed to these matters, such response must be supplemented to include the name, address and telephone number of the expert witness
and the substance of the testimony concerning which the expert witness is expected to testify,
as soon as practical, but in no event less than thirty (30) days prior to the beginning of trial except on leave of court.
Tex.R.Civ.P.Ann. 166b(6)(b) (Supp.1991) (emphasis added). A party who fails to supplement his response to a discovery request may not offer the testimony of an expert witness unless the trial court finds good cause exists to require admission of the testimony. Tex.R.Civ.P.Ann. 215(5) (Supp.1991);
see also Morrow v. H.E.B., Inc.,
714 S.W.2d 297, 297-98 (Tex.1986) (the sanctions are automatic unless good cause is shown). The party offering the evidence has the burden of establishing good cause, which must be shown in the record.
Gee v. Liberty Mut. Fire Ins. Co.,
765 S.W.2d 394, 395 (Tex.1989);
Morrow,
714 S.W.2d at 298.
Although the record is incomplete, we gather that in response to interrogatories the Defendants supplied Dr. Tindall’s name, address and telephone number. They also identified Dr. Tindall as an expert who might testify “regarding the alleged injury of plaintiff and her physical and mental condition.” The Defendants did not supplement this response, even after it became apparent at Dr. Tindall’s deposition that he expected to testify as an expert on “brain-mapping,” a controversial diagnostic technique.
We cannot appraise the Defendants’ assignment of error. We must presume that the proceedings and judgment below were regular and correct. The burden lay upon the Defendants to supply us an appellate record demonstrating the trial court abused its discretion in excluding Dr. Tin-dall’s testimony because they failed to supplement their answers as required. Tex. R.App.P.Ann. 50(d) (Pamph.1991);
Christiansen v. Prezelski,
782 S.W.2d 842, 843 (Tex.1990). The Defendants were obliged therefore to include in the appellate record the interrogatories and answers. They did not.
The Defendants contend the burden lay upon Hinton to bring forward on appeal, in the record, the written interrogatories; and, because she did not, there is nothing to show a proper basis for excluding Dr. Tindall’s testimony. We reject the contention because it reverses the presumptions mentioned above. We must presume, rather, that the missing documents would sustain the trial-court ruling.
Forestpark Enter. v. Culpepper,
754 S.W.2d 775, 778 (Tex.App.1988, writ denied).
Alternatively, the Defendants contend their burden was satisfied by the statement of facts, which includes statements by opposing counsel describing the answers to the written interrogatories. Some are in quotation marks and appear to be quotations and summaries of those answers. We cannot appraise from these statements alone whether the trial court abused its discretion. There is nothing to indicate that these statements are complete or reasonably accurate summaries or quotations of the answers. More importantly, these statements do not include the
questions
posed in Hinton’s written interrogatories.
We therefore overrule points of error six and seven complaining of the exclusion of Dr. Tindall’s testimony.
VIDEOTAPED EXPERIMENT
In their eighth and ninth points of error, the Defendants contend the trial court erred when it allowed the jury to view, over objection, a videotape of an out-of-court experiment conducted by Hinton’s witness, a Mr. Bruñe. The videotape showed a plywood cutout, the size of the plastic grate, falling and striking a dummy. The cutout represented the plastic grate; the dummy represented Hinton. As they did at trial,
the Defendants contend the experiment was not substantially similar to the actual event and the prejudicial effect of the videotape outweighed any probative value it might have had. They argue that the heavier plywood cutout struck the dummy with much greater force than the plastic grate struck Hinton, leaving the jury with an erroneous and prejudicial impression in that regard.
Where, as here, the experiment is made out of court and in the absence of opposing counsel, there must be a substantial similarity between the conditions depicted on the videotape and the actual event that is the subject of litigation.
Fort Worth & Denver Ry. Co. v. Williams,
375 S.W.2d 279, 281-82 (Tex.1964);
Wells v. HCA Health Servs.,
806 S.W.2d 850, 853 (Tex.App.1990, writ denied). The conditions of the occurrence and experiment need not be identical.
Williams,
375 S.W.2d at 282. The test for exclusion is whether the experiment would confuse rather than aid the jury.
Id.
The trial court has broad discretion in determining the admissibility of an out-of-court experiment, and a reviewing court will not overturn the trial court’s decision absent an abuse of discretion.
Wells,
806 S.W.2d at 853. This is particularly true if the dissimilarity is minor or
if the differences are explained to the jury. Williams,
375 S.W.2d at 282.
We cannot conclude the trial court abused its discretion. Bruñe testified that the videotaped experiment was not meant to be an exact duplication of the incident in which Hinton was injured. He explained that he used plywood in his re-creation of the accident, instead of a plastic grate, because he did not have access to a grate similar to the one which fell on Hinton. On cross-examination he testified that the purpose of the exhibit was to show how the grate fell, not how forcefully the grate struck Hinton. We do not believe that the experiment reasonably could have confused the jury by causing them to believe the incident occurred precisely as depicted on the videotape.
Even if the trial court abused its discretion in admitting the videotaped experiment, we do not believe the Defendants have carried their burden on appeal. To obtain reversal of a judgment based upon an error of the trial court in admitting or excluding evidence, the appellant must show (1) that the trial court erred, and (2) that the error was reasonably calculated to cause and probably did cause the rendition of an improper judgment.
Gee,
765 S.W.2d at 396. The appellate court must examine the entire record to determine whether the disputed evidence controlled the judgment.
Id.
Bruñe stated explicitly to the jury that the experiment did not indicate how forcefully the grate struck, but only how the grate fell. We find in the record nothing to diminish the effect of this qualifying statement, and nothing to indicate that the jury disregarded it. The amount of damages found by the jury does not in and of itself indicate harm to the Defendants — the damages question asked the jury did not distinguish between psychological and physical injury, or between “physical pain, mental anguish, and physical impairment.” In this state of the record, we would act without basis were we to conclude that the admission of the videotape experiment amounted to such a denial of the Defendants’ rights as was calculated to cause and probably did cause rendition of an improper judgment, even if admission of the videotape did constitute an abuse of discretion and therefore error. Tex.R.App.P.Ann. 81(b)(1) (Pamph.1991).
We hold accordingly and overrule the eighth and ninth points of error.
ADEQUACY OF JURY ANSWERS
Question No. 1 of the charge asked whether the Defendants were “negligent”
and whether “such negligence, if any, was a proximate cause of Plaintiffs injury, if any?” Questions 2, 3, and 4 asked, respectively, whether the Defendants were “responsible for the condition of the light cover which allowed it to fall”; whether their “conduct with respect to the condition in the light cover” was “negligence”; and whether such “negligence [was] a proximate cause of the occurrence in question?” The jury answered each question “Yes.”
In their tenth point of error, the Defendants complain that these answers were insufficient to establish their liability. They contend that Hinton has
only
a premises-liability claim, and argue that the jury’s answers will not support such a claim.
The Defendants apparently contend that specific findings were required concerning: (1) whether Hinton’s status in the Academic Center was that of a licensee or an invitee; (2) whether the Defendants’ conduct fell within the character necessary to create liability under either status (gross negligence if Hinton was a licensee or failure to make the premises reasonably safe if she was an invitee); and (3) whether the Defendants knew of the unsafe condition of the light fixture or should have known of it in the exercise of ordinary care.
The charge included the ordinary definition of “negligence,” that is to say, a “failure to use ordinary care” or a failure “to do that which a person of ordinary prudence would have done under the same or similar circumstances or doing that which a person of ordinary prudence would not have done under the same or similar circumstances.”
We believe the jury answers to the broad-form submission of “negligence” will support the verdict. First, a premises-liability case should be tried upon general negligence principles.
See Corbin v. Safeway Stores, Inc.,
648 S.W.2d 292, 295 (Tex.1983) (“[T]he standard of conduct required of a premises occupier toward his invitees is the ordinary care that a reasonably prudent person would exercise under all the pertinent circumstances.”);
see also Tanner v. BDK Prod. Co.,
671 S.W.2d 941, 943-44 (Tex.App.1984, no writ).
The provisions of Texas Rule of Civil Procedure 277 authorize the submission of broad-form questions when “feasible.” Tex.R.Civ. P.Ann. 277 (Supp.1991).
Second, the trial court was bound by the law of the case established in
Hinton v. University of Texas at Austin,
No. 13,962 (Tex.App.—Austin, Apr. 11, 1984, no writ) (opinion not published). There, we held that Hinton “was not a mere licensee, but enjoyed the status of a ‘business invitee.’ ” This fixed,
as a matter of law,
the two propositions that (1) Hinton was an invitee and (2) the Defendants owed a duty to make the premises reasonably safe for her. Consequently, there was no issue of fact concerning those propositions that a jury might determine.
See Allied Fin. Co. v. Shaw,
373 S.W.2d 100, 106 (Tex.Civ.App.1963, writ ref’d n.r.e.) (“The holdings announced in a former appeal constitute the law of the case.”). We believe, in addition, that the general negligence-res ipsa loquitur inquiry of Question Number 1 included an inquiry whether the light fixture was unsafe and whether the Defendants knew or should have known of its condition under the standard of ordinary care.
See
Tex.R.Civ. P.Ann. 277 (Supp.1991);
St. Louis Southwestern Ry. Co. v. Lawrence,
91 S.W.2d 434, 436 (Tex.Civ.App.1936, no writ) (“That the defendant knew, or by exercise of ordinary care could have known, of the defective condition of the step is embraced within the jury’s verdict in response to the general and ultimate issue of negligence.”).
The Defendants appear to argue as well, under the same point of error,
that the doctrine of res ipsa loquitur, embraced in Question Number 1, is impermissible under the scope of the state’s waiver of sovereign immunity. We disagree. The doctrine, where applicable, simply permits an inference of negligence from the happening of the event alone.
Lemos v. Montez,
680 S.W.2d 798, 801 (Tex.1984). It is not a ground of recovery independent of negligence.
For the reasons given, we overrule point of error ten.
CUMULATIVE ERROR
In their eleventh point of error, the Defendants contend that, even if none of the alleged errors is sufficient by itself to warrant reversal, the cumulative effect of all of the errors justifies our reversing the judgment and remanding the cause for a new trial.
The supreme court has long recognized the doctrine of cumulative error.
See Smerke v. Office Equip. Co.,
138 Tex. 236, 158 S.W.2d 302, 305 (1941);
see also Standard Fire Ins. Co. v. Reese,
584 S.W.2d 835, 840 (Tex.1979). A reviewing court may reverse a lower-court judgment under the cumulative-error doctrine when the record shows a number of instances of error, “no one instance being sufficient to call for a reversal, yet all the instances taken together may do so.”
Sproles Motor Freight Lines, Inc. v. Long,
140 Tex. 494, 168 S.W.2d 642, 645 (1943).
In our analysis of the Defendants’ first ten points of error, we found no error by the trial court. We therefore overrule the Defendants’ eleventh point of error.
PREJUDGMENT INTEREST
Hinton concedes that the Texas Tort Claims Act provides a statutory limit of $100,000 on damages, but she contends in a cross-point that the trial court erred by subtracting prejudgment interest from her damage award. She contends the Act applies only to “money damages,” and prejudgment interest does not fall within that category. We disagree.
At the time of Hinton’s injury, the Texas Tort Claims Act limited the liability of a unit of state government to $100,000.
See
Texas Tort Claims Act, 1969 Tex.Gen. Laws, ch. 292, at 874 (Tex.Rev.Civ.Stat. Ann. art. 6252-19, § 3, since repealed and codified as amended at Tex.Civ.Prac. & Rem.Code Ann. § 101.023(a) (Supp.1991)). The Texas Supreme Court has held that the Act precludes the award of prejudgment interest when the damages found by the jury exceed $100,000.
Weller v. State,
682 S.W.2d 234, 234 (Tex.1984).
Hinton advances several arguments in support of a contention that
Weller
no longer controls on this issue. She argues first that the supreme court impliedly overruled
Weller
in
Cavnar v. Quality Control Parking, Inc.,
696 S.W.2d 549 (Tex.1985). In
Cavnar,
the supreme court said, “We therefore hold that, as a matter of law, a prevailing plaintiff may recover prejudgment interest compounded daily ... on damages
that have accrued by the time of judgment.
To the extent that other cases conflict with this holding, they are overruled.”
Id.
at 554 (emphasis in original). Hinton contends that
Weller
conflicts with
Cavnar
and was thus overruled.
We believe
Weller
does not conflict with
Cavnar.
Like Hinton’s case,
Weller
involved a suit against a governmental unit. In contrast,
Cavnar
was a suit between private parties. To hold that the supreme court overruled
Weller
in
Cavnar,
we would have to hold that the supreme court
impliedly
interpreted section 101.023 of the Civil Practices and Remedies Code to allow prejudgment interest in excess of the statutory limit on the state’s liability. This we decline to do.
We believe the supreme
court had to specifically apply its prejudgment interest rule to governmental units to overrule
Weller.
Although the supreme court used broad language in
Cavnar,
we cannot conclude that it intended by its decision an implied and general waiver of a governmental unit’s immunity from liability for sums in excess of the $100,000 fixed by the legislature in the Tort Claims Act.
See Whipple v. Deltscheff,
731 S.W.2d 700, 705 (Tex.App.1987, writ ref’d n.r.e.) (rejecting without discussion of
Cavnar
a claim that a plaintiff could recover prejudgment interest in excess of the statutory limit on liability).
Hinton asserts next that her claim for prejudgment interest comes within an exception to the statutory “cap,” which limits the amount of “money damages” a party can recover. Tex.Prac. & Rem.Code Ann. § 101.023 (1986 & Supp.1991). She argues that
Cavnar
established a distinction between prejudgment interest and money damages; therefore, prejudgment interest is not subject to the statutory limitation on money damages. We reject this reasoning as well. Even statutory language is subject to the interpretive rule that a waiver of governmental immunity will not be inferred in the absence of clear and unambiguous language.
Duhart v. State,
610 S.W.2d 740, 742 (Tex.1980). The language of
Cavnar
contains no clear and unambiguous abolition of the government’s immunity from liability, in whole or in part. Because the legislature has not expressly waived the Defendants’ immunity in prejudgment interest claims,
Cavnar
provides no exception to the rule of statutory immunity.
See City of Houston v. Arney,
680 S.W.2d 867, 875 (Tex.App.1984, no writ) (stating that sovereign immunity cannot be waived by implication, but must be expressly waived);
see also University of Tex. Medical Branch v. York,
808 S.W.2d 106, 111 (Tex.App.1991, pet. filed) (denying prejudgment interest in a suit against a governmental entity);
Whipple,
731 S.W.2d at 705 (same).
In her third argument, Hinton points to article 5069-1.05, which, as recently amended,
requires
a trial court to award prejudgment interest in personal-injury cases. Tex.Rev.Civ.Stat.Ann. art. 5069-1.05 (Supp.1991). She argues that this statutory change confers upon her a statutory right to interest and renders
Weller
inapplicable. We reject her reasoning on several grounds. The 1987 amendment to article 5069-1.05 applied only to an action commenced on or after September 2, 1987.
See
1987 Tex.Gen.Laws, 1st C.S., ch. 3, § 3, at 52. Hinton filed her suit in 1980, well before the effective date of the amendment to article 5069-1.05. Therefore, she has no statutory right to prejudgment interest. Even assuming she had such a right, the amendments do not purport to deal with the matter of prejudgment interest in relation to sovereign immunity. In the absence of an explicit waiver of sovereign immunity by the legislature, we cannot impute to the amendments such a waiver by implication.
Finally, Hinton argues that, as a matter of public policy, the prejudgment interest statutes should apply to the state as well
as to private litigants. She contends the state, which benefits from a statutory limit on damages, has no incentive to settle a case or to go to trial. As evidence of this, she declares that “the state allowed this case to drag on for ten years.” We find the argument strained in light of the record presented to us on appeal. The record shows that Hinton filed motions for continuances regarding trial settings in 1983, 1985, 1986 and 1988. While it is possible the state abuses its protection from prejudgment-interest awards in some cases, we do not believe it did so in this case, and it is a matter for the legislature’s consideration in all events. We overrule Hinton’s cross-point of error.
Finding no error in the trial court’s actions, we affirm the judgment below.