Nabors Well Services, Ltd. v. Romero (508 S.W.3d 512, 2016)

OPINION

ANN CRAWFORD McCLURE, Chief Justice

In this appeal we once again visit a tragic accident between a family traveling for the Christmas holidays and an oil field service vehicle. For the reasons noted below we reverse and remand in part, and affirm in part.

PROCEDURAL HISTORY

This case returns to us from the Texas Supreme Court. On initial review, we affirmed the trial court which had excluded evidence related to the alleged non-use of seat belts by most of the Appellees. Nabors Wells Services, Ltd. v. Romero, 408 S.W.3d 39, 41 (Tex.App.-El Paso 2013), rev’d, 456 S.W.3d 553 (Tex.2015). Appellants, who we collectively refer to as Na-bors, sought to introduce evidence to show that the Appellees failed to use their seat belts, or failed to require others to use seat belts, which enhanced their injuries from the accident. We affirmed the trial court’s exclusion of the evidence based on Carnation Co. v. Wong, 516 S.W.2d 116 (Tex.1974) which was the controlling law at the time.

On petition for review, however, the Texas Supreme Court concluded that the rationale of Carnation was no longer viable in light of intervening legislative and societal changes. 456 S.W.3d 563. In overruling Carnation, the court held: “relevant evidence of use or nonuse of seat belts, and relevant evidence of a plaintiffs pre-occurrence, injury-causing conduct generally, is admissible for the purpose of apportioning responsibility under our proportionate-responsibility statute, provided that the plaintiffs conduct caused or was a cause of his damages.” Id. at 566-67. That still the leaves the question of whether this new rule requires a reversal in this case. The Texas Supreme remanded that issue for our consideration. Id. at 566.

We are generally faced with two questions in reviewing a trial court’s decision to exclude evidence: was the exclusion error, and if so, was the exclusion harmful? Gee v. Liberty Mutual Fire Insurance Co., 765 S.W.2d 394, 396 (Tex.1989). The Texas Supreme Court’s holding answers the first question for some of the excluded evidence in this case: if the evidence was excluded only on the basis of Carnation, the exclusion was error. But that leaves additional inquiries on remand: Was there any other valid basis for the exclusion of the evidence that the trial court relied on, and for any improperly excluded evidence, was the exclusion harmful? Appellees believe the first question is particularly relevant here, as the trial court excluded Nabors’ biome-chanical expert, at least in part, based on Tex. R. Evid. 702 grounds as articulated in E.I. du Pont de Nemours & Co. v. Robinson, 923 S.W.2d 549 (Tex.1995). Appellees also raise additional waiver issues which we did not address on first hearing the case. With that overview of the task before us, we turn to the evidence in the case.

FACTUAL BACKGROUND

On December 20, 2004, Martin Soto was driving his family from California to Mexico for the Christmas holidays. They were traveling in a 1993 Chevrolet Suburban. Martin did all the driving and his wife, Esperanza, was in the front passenger seat. Their nine-year-old daughter, Mar-ielena Soto, was in an aftermarket seat that had been installed between the front driver and front passenger seats.

The Suburban had two rows for passenger seating. The Sotos’ fifteen-year-old twins—Esperanza (who we will refer to by her nickname “Mino”) and Guadalupe were in the middle row. Mino was most likely seated behind the driver’s seat, and Guadalupe was seated behind the front passenger seat. In the back row, Martin Soto’s stepdaughter, Aydee Romero, was in the middle seat. Her children, Edgar Romero and Saul Romero, were to either side of her. There is some dispute in the evidence as to which child was on the right and which on the left.

The Accident

At about 4:30 a.m. the Suburban was headed Southbound on U.S. 285 just outside of Fort Stockton, which at that point is a two lane highway. The Suburban was overtaking a Nabors oil field service truck being driven by Lauro Garcia, which was also southbound. Martin moved into the on-coming lane of traffic to pass the slower moving Nabors vehicle. As he was passing the Nabors truck, however, it began a left hand turn which caused the two vehicles to collide. Upon impact, the Suburban skidded to the side, rotated clockwise, and then began rolling over with driver’s side leading the roll. It made three com-píete revolutions before coining to rest upright on its tires. A rollover with three complete revolutions would rank in the top 0.2 percent in terms of severity for such accidents.

Had the trial court allowed evidence about the use or non-use of seat belts, there would have been sharply disputed evidence about whether some of the occupants were belted. A Department of Public Safety report noted that all but Mar-ielena and Esperanza Soto were unbelted at the time of the accident. Depositions taken in the case, however, yielded testimony that Esperanza, Marielena, and Mino were unbelted. There was also a dispute over who was ejected from the Suburban in the crash. The same DPS report concluded that only Aydee Romero was ejected. The DPS officer who completed the report, however, did not arrive on the scene until an hour and half after the accident. The EMTs on scene reported that one of the Appellees, likely Guadalupe, stated that all but one of the Appel-lees were ejected in the accident.

The Injuries, Evidence of Seat belt Use, and Ejection

We summarize each Appellee’s injuries and the evidence about belt use and possible ejection from the Suburban.

Martin Soto

Martin Soto was belted and stayed in Suburban as it rolled over. Following the accident, he stayed at the scene until well after the other occupants of the Suburban were transported by ambulance. He later went to the Pecos County Hospital Emergency room and was evaluated for complaints of neck, rib, and shoulder pain. He was released that same day and introduced no evidence of follow up care.

Esperanza Soto

An EMT who arrived on the scene at 5:22 a.m. found Esperanza lying on the ground on her right side with multiple right side injuries. The EMT noted she was ejected from the vehicle and that she had “road rash” abrasions to her right side. The emergency room record states she was ejected from the vehicle, but she herself had no memory of the accident. Her husband testified that she was ejected. She fractured her pelvis and hip, broke several ribs on her right side, perforated a lung, and had a hairline fracture to the right shoulder. Nabors could have presented direct testimony that she was unbelted at the time of the accident.

Marielena Soto

Marielena was the first priority patient at the scene. By the time EMTs arrived, the fire department already had her on a backboard. She was assessed with possible fractures and a closed head injury; she was largely unresponsive. At Pecos Memorial Hospital, she was intubated and prepared for air transport to a pediatric ICU unit in Lubbock. She was still unresponsive by the time she arrived in Lubbock and remained on a ventilator for two days. She had a partially collapsed left lung. When she regained consciousness, she complained of left heel pain, which turned out to be a fractured calcaneus bone in her foot. Marielena had an orbital fracture from the head trauma which was sufficiently severe to cause a subdural he-matoma and severe brain trauma. She lost vision in her right eye from the orbital fracture The resulting frontal orbital syndrome lead to a severe traumatic brain injury. Marielena was in the pediatric ICU unit in Lubbock for eleven days. Her medical record contains multiple references to an ejection after an automobile accident. Nabors could have presented some direct testimony that Marielena was unbelted.

Mino Soto

Mino was found by the EMTs. lying on the street. She was minimally responsive and had a large abrasion on her right arm and shoulder. Her condition began to deteriorate while being transported to the local hospital. Once there, she was intu-bated and air-flighted to a pediatric ICU in Lubbock. She was diagnosed with. a closed head injury, resulting in a small subdural hematoma. She on a ventilatpr for two days and remained- in the hospital a total of eleven days. Her discharge summary from the hospital notes that she was ejected in the accident She had abrasions on both of her arms and face which a treating doctor agreed were consistent with road rash, which in turn is consistent with an ejection injury. She testified at trial to having a road rash scar. Multiple other medical records similarly recite,that she, was ejected. Nabors could have presented direct testimony that she was un-belted.

Guadalupe Soto

Guadalupe was found ambulatory at the scene by the EMTs. She had an avulsion injury to her finger (her finger nail was detaching from the finger and was removed) and she had a few scratches and cuts. While the ER physician believed she had been ejected, as did Martin, she testified that she was belted at the time of the, accident.

Aydee Romero

The DPS report and depositions of all the participants agree that Aydee Romero was ejected from the Suburban. She died at the scene. Photos show her body lying on the pavement with apparent blood pooling around her head. One photo shows considerable abrasions to her body. The death certificate, completed by a local justice of the peace, reported the cause of death as blunt injuries to the head. The investigating DPS officer would have testified that Aydee was not wearing a seat belt at the time of the accident.

Edgar Romero

Edgar Romero, age eight, was found by the ambulance crew on the ground crying when they arrived on the scene. He complained of pain to his right shoulder and knee. Edgar was brought by ambulance to the emergency department of Pecos County Medical Center and was assessed with a fractured right clavicle and right knee injury. The emergency room record recites that he was ejected in the accident. The ER physician believed he had been ejected. Edgar was transferred to a hospital in Odessa that same day which confirmed the fractured clavicle. Guadalupe Soto testified that she helped Edgar out of the vehicle following the accident, but Edgar himself reportedly testified on deposition that he was ejected.

Saul Romero

Saul Romero suffered a fractured left clavicle, a small cut and bump to the left side of his head, and abrasion to his left hand. The Pecos County ER records reported he suffered an ejection injury. The only evidence of his seat belt use is found in the DPS report which stated he was unrestrained.

The Seat Belt Defense and Exclusion of James Funk, PhD.

Nabors pled that Martin Soto was con-tributorily negligent not only with regard to the cause of the accident, but also in “failing to assure that all passengers in his vehicle. had their safety belts secured.” Nabors asserted this defense as both negligence and negligence per se. At the time of this accident, the Texas Transportation Code would have required Martin and Esperanza as front seat occupants to be belted. Act of June 14, 2001, 77th Leg., R.S., ch. 910, § 2, 2001 Tex.Gen.Laws 1821, 1821-22 (amended 2005, 2007, 2009, 2013)(current version at TexTransp. Code Ann. § 545.413(b)(West Supp.2015). It also would have required Martin, as the driver, to have any child (of at least age four but younger than seventeen) anywhere in the vehicle to be belted. Id. Nabors’ answer further alleged that each Appellee was contributorily negligent in not buckling themselves in. Under the heading “Failure to Mitigate,” the pleading asserted that Nabors was not responsible for any injuries resulting from any person failing to secure their own safety belt, or failing to require their child to be secured in a safety belt. Appellees attacked this portion of Nabors’ pleading through a partial motion for summary judgment which the trial court granted just before trial. It was that ruling which generally led to the exclusion of any reference to seat belts in the case.

Nabors was prepared to advance its seat belt defense through is designated expert, James Funk, PhD. Funk has a bachelor of science, master’s, and doctorate degree in biomedical engineering. He described his field as the study of the relationship between forces and resulting injury patterns. As a part of his schooling, he took course work that both medical students and engineers might take, including chemistry, biology, anatomy, physiology, physics, biophysics, and mechanical engineering. In his master’s degree program, he performed research at the University of Virginia Medical School’s orthopedics department. As a part of his doctorate program, he worked in an automobile safety laboratory which intentionally injured cadavers to understand the relationship between the forces and ensuing injury.

He continued as a research scientist for UVA for several years until he began working for Biodynamic Research Corporation, where he investigates automobile crashes. Three-fourths of his time is spent on litigation matters. The other part of his work involves research, such as a government sponsored project on rollover crashes through the University of Virginia. By the time of this trial, his resume referenced fourteen peer reviewed articles that he co-authored on various aspects of biomechanics, including several on rollover accidents. The same resume referenced twenty-eight peer-reviewed conference publications and multiple other publications and invited presentations. He is not a medical doctor and would not be licensed to practice medicine in the State of Texas.

Dr. Funk’s Opinions

Dr. Funk’s basic methodology starts with understanding the dynamics of how the vehicles move during the crash. From that, he determines the movement and forces applied to the occupants of the vehi-ele. Once he estimates the amount and direction of the biomechanical forces applied to the occupants, he then determines which injuries were caused by the accident. Following this methodology, he expressed several opinions in this case which we categorize as follows:

Seat Belt Usage Opinions

Dr. Funk reviewed the deposition testimony taken of the Appellees and other witnesses, the medical records, and accident reports from the case. He was prepared to summarize the evidence as to whether each Appellee was belted, and whether any particular Appellee was ejected from the Suburban. For instance, the DPS report states that Martin Soto was unrestrained, while Martin testified that he was belted, a fact also supported by the medical record entries. The DPS report noted that Esperanza Soto was not ejected and had her -shoulder and lap belt engaged. The medical records and Esperanza’s own testimony, however, contradicted the DPS report on both issues. There were similar disputes with all the Appel-lees, other than everyone agreed that Ay-dee Romero was ejected. Dr. Funk prepared a chart as a part of his presentation which would have summarized the conflicting evidence on these topics.

Given these discrepancies, Dr. Funk was also designated to provide an opinion regarding what the physical evidence showed as to seat belt use. He had inspected the seat belts in the vehicle (three and one-half years post-accident) as well as the photographs taken after the accident. He concluded that the physical evidence was inconsistent with anyone but Martin wearing a seat belt. Martin’s seat belt showed markings that matched up with a “D ring” on the seat belt assembly, which Dr. Funk interprets as “loading” from the force of Martin’s body pulling on the belt during the accident. None of the other seat belts showed this loading. The other belts had markings and scuffs on the portion of the webbing that is exposed when the seat belt is retracted and not in use. The portion of the belt that would be exposed if it were engaged, however, was pristine and had no such marks. He also notes that he when inspected the vehicle, the seat belts for Marielena and Aydee were not adjusted properly to fit them (they would have been either too tight or too loose on the wearer).

Physics Of Belted Versus Unbelted Passengers

Dr. Funk also described the likely movements of Appellees’ bodies during this accident. Consistent with an accident reconstruction expert, he divided the crash into two phases: an initial sideswipe of the Suburban and Nabors’ truck, and then a second phase where the Suburban slides, rotates, and rolls over. With the first impact between the Suburban and the Na-bors’ truck, an occupant of the Suburban would move to front and left, and then possibly rebound from anything they may have struck. As the vehicle rotated and began to rollover, centrifugal force would have then dominated. The vehicle rolls in circular pattern. For the occupants to also move in that same circular pattern, they must either be restrained by a seat belt, or if not, by the perimeter of the vehicle. In a rollover, the windows will often break from ground contact leaving a portal for ejection. If unrestrained, centrifugal force will push the occupants out of the vehicle.

An ejection can occur on the high side, throwing the occupant up and out in a ballistic trajectory. In that event, the occupant may be thrown beyond the path of the vehicle, land, and then slide until they come to a rest. An occupant can also be ejected on the low side, meaning they are left behind as the vehicle continues to roll. Dr. Funk was prepared to demonstrate these movements with a video of an actual crash, using six crash test dummies in an SUV. The video showed both high side and low side ejections of five of the six test dummies.

Dr. Funk was unable to conclude through which opening any particular Ap-pellee would have been ejected. He did find evidence of ejection on the vehicle, such as hair on window openings. With regard to Aydee, he knew her final resting point and by working backwards, he was able to calculate eight possible trajectories that her body could have taken. They all resulted in a severe ground impact with the pavement at a speed between 30 to 47 miles per hour.

Likelihood Of Ejection With And Without Seat Belts

Dr. Funk also offered the opinion that seat belts are 99.9 percent effective in preventing ejections in rollover accidents. In crash tests, seat belts have never failed to prevent ejections. In the few real world instances of belted ejections that Dr. Funk has investigated, there was a significant force from the rear (a high speed rear end collision) which caused the seat back to fail. Conversely, Dr. Funk concluded that unbelted occupants have an 80 percent chance of ejection in a three-revolution rollover. This conclusion is based on various studies which we discuss in more depth below.

Dr. Funk made an exception to this analysis for Marielena who was in an aftermarket seat added between the two front seats. That seat had been purchased from Western Auto, and installed by Martin. The seat back broke from the seat bottom which would have impaired the effectiveness of the seat belt.

Injury Potential Of The Accident

The Suburban and the Nabors truck initially collided as the Nabors truck began its left hand turn. From the scene photos, the front bumper of the Nabors truck was tom off. As a part of Dr. Funk’s analysis, he first attempted to estimate the severity and injury potential of this first impact. From information developed by an accident reconstructionist, he estimated the change in speed of the Suburban (which he refers to as “Delta V”) as between five to ten miles per hour. He concluded that “the risk of serious injury in a minor frontal like this is very low. It’s less than two percent.” He based this opinion on one of his own studies done in 2008.

Turning to the rollover phase of the accident, Dr. Funk calculated the centrifugal force experienced by the occupants as between three to six g-forces, equivalent to the same force one might feel on a roller coaster ride. He concluded that level of the g-forces in and of themselves would not likely cause any injuries. Roof collapse is another peculiar risk of rollovers. There is a high risk of injury if a person is pressed up against the relatively thin roof when it impacts the ground. He examined the roof of the Suburban and found “almost non-existent” damage. From this, he concluded there were no significant roof to ground impacts, and therefore a low risk of injury for occupants inside the vehicle. Dr. Funk acknowledged that the Suburban was carrying unrestrained luggage and cargo, which would have reacted just as an unrestrained person would have during the rollover. Because the items are moving in the same direction and speed as the occupants, he contends any risk of injury from the cargo striking an occupant is low. The abrasion injuries sustained by the some of the Appellees here were also described as “road rash” which would be different from a compression injury caused by luggage striking someone.

Dr. Funk then concluded the most serious risk of injury facing the Appellees was an ejection injury. The risk of serious injury or death for a person ejected in a rollover is five to ten times higher than a non-ejected person. For rollovers, he concluded that the risk of serious injury or death is 10 percent for a non-ejected occupant, but is 70 percent for an ejected occupant. His analysis appears to be based on several studies that conclude that unbelted occupants suffer greater injuries in severe rollover accidents than belted passengers: Malliaris and Digges, 1987; Parenteau and Shah; Digges and Eigen, 2003; Moore, 2005; and Gloeckner, 2006. He also relied on several more of his own papers. We discuss each of these studies below.

Dr. Funk then attempted to tie in the specific medical conditions of each Appel-lee, as disclosed in the medical records, to his theory. Martin, who was restrained, suffered relatively minor injuries compared to the others. Conversely, Mariele-na, who was seated next to him but was ejected, suffered a severe head trauma and showed signs of road rash from the impact. Similarly, Esperanza had a series of right side injuries (thorax, shoulder, pneumotho-rax, lung contusion, rib fracture) which were consistent with an impact with the ground on her right side. She had road rash on that side as well. Dr. Funk in his doctorate work had seen these kinds of injuries from cadaver studies. Esperanza also had a fractured hip; the x-ray report noted foreign bodies (glass fragments and stones) imbedded in the skin on the right hip. He excluded Esperanza striking her head on the front of the windshield based on the lack of fracture patterns on the windshield showing an impact point.

Dr. Funk tied Mino’s injuries to his theory by noting her closed head injury and road rash abrasions which he concluded were impact injuries. He tied Aydee’s injuries to his theory based on the impact injury to her head, which is listed on the death certificate as the cause of death. Based on cadaver studies, her calculated impact at BO to 47 miles per hour was well in excess, of that need to cause a catastrophic head injury. He further based his opinion on her position in a middle seat, where she would be otherwise protected from impacting the side of the vehicle, The absence of roof damage suggests she would have avoided a head injury had she stayed in her seat.

With regards to Edgar and Saul, who each had clavicle fractures on the right and left shoulder respectively, Dr. Funk believed those injuries were consistent with where he believes they were seated in the vehicle (on the right and left side respectively).

The Basis of the Challenge

Appellees filed a pretrial motion challenging Dr. Funk’s opinions. They generally asserted that his testimony did not meet the qualification and reliability requirements of Tex. R. Evid. 702. Part of the motion focused on Dr. Funk’s employer, Biodynamic Research Corporation, and contended the opinions of other persons working for that company have been struck in other courts. Specifically with regard to Dr. Funk’s opinions in this case, Appellees contended they would not assist the .trier of fact because they contain “gaps” or- are based on speculation. Ap-pellees further alleged that Dr. Funk was not qualified to render a medical causation opinion because Dr., Funk is not a medical doctor, nor has he .had practical experience in the field of medicine. The motion was also premised on Dr. Funk being trained in biomedicine, .and not biomechanical engineering. Finally, Appellees challenged the underlying data that Dr. Funk relied on—the studies of rollover injuries—as failing the basic reliability standards found in Texas law.

The Trial Court’s Ruling

The trial court excluded Dr. Funk’s opinions on “injury causation” because they would not “assist the trier of fact.” This ruling included the statistical information on incidence of injury when a person is ejected versus not being ejected. Nor could Dr, Funk testify to the eight ejection scenarios for Aydee. The order the trial court later entered also excluded any testimony regarding Dr. Funk’s, inspection of the vehicle’s seat belts. The court preserved his ability to testify to the mechanics of the rollover. At the same hearing, the trial court granted Appellees’ partial summary judgment on the seat belt issue, which effectively excluded other evidence of seat belt use/non-use.

The Verdict

The jury returned a verdict assessing 51 percent of the fault to Nabors and its employee. The jury found Martin 49 percent at fault. Nabors did not request, nor did the charge contain any issue or instruction which would have permitted the jury to consider the failure to use seat belts by any Appellee. The jury awarded damages to each of the Appellees, other than to Asuncion. The individual awards to the other Appellees totaled just over $2.3 million.

WAS EXCLUSION ERROR?

Waiver Issues

At the outset, we address two waiver issues that Appellees advance. First, they contend that because Nabors failed to request an issue or instruction which would have allowed the jury to consider the seat belt defense, Nabors has waived any consideration of the issue on appeal. Nabors counters that once the trial court excluded its evidence, it had no right to ask for a jury question or instruction, and it has not waived its defense. We agree with Nabors.

A party is entitled to have an instruction or question submitted for any legally viable claim or defense which is supported by the pleadings and the evidence. Tex. R. Civ. P. 278; Elbaor v. Smith, 845 S.W.2d 240, 243 (Tex.1992). Once the trial court excluded the seat belt evidence, and granted Appellees motion for partial summary judgment negating Nabors pled defense, it had no right to obtain an issue or instruction on the seat belt defense. See Placencio v. Allied Indus. Intern., Inc., 724 S.W.2d 20, 22 (Tex.1987)(no error in refusing instruction on defense which the evidence did not support). If Nabors had no right to request a question or instruction on its seat belt defense, it likewise had no obligation to tender proposed questions or instructions on that defense. Appellees cite no precedent requiring such a tender, and we find none. Accordingly, we reject Appellees waiver claim based on the absences of tendered questions or instructions.

Next, Appellees contend that Na-bors briefing is deficient in that it does not contain a specific issue regarding the exclusion of Dr. Funk. Under Tex. R. App. P. 38.1(f): “[t]he brief must state concisely all issues or points presented for review. The statement of an issue or point will be treated as covering every subsidiary question that is fairly included.” To be clear, Nabors briefing specifically addresses the trial court ruling on Dr. Funk, and argues each of the Rule 702 grounds that Appel-lees raised below. The only deficiency is that there is not a separate issue on appeal addressed to that ruling. We disfavor disposing of appeals for harmless procedural defects. Verburgt v. Dorner, 959 S.W.2d 615, 616 (Tex.1997). We also construe appellate briefs reasonably, yet liberally, so that the right to appellate review is not lost by waiver. See El Paso Natural Gas v. Minco Oil & Gas, Inc., 8 S.W.3d 309, 316 (Tex.1999). Appellate courts should reach the merits of an appeal whenever reasonably possible. See Verburgt, 959 S.W.2d at 616. Accordingly, we decline to find a waiver here and believe the issue of Dr. Funk’s exclusion is a subsidiary question which has been fairly raised. See Perry v. Cohen, 272 S.W.3d 585, 587 (Tex.2008)(fínding no waiver when the issue raised did not specifically challenge trial court’s interlocutory order but the arguments under the issue did.). According, we turn to the merits of the issue.

Exclusion of Dr, Funk’s Opinions

We review a trial court’s rulings on the admissibility of evidence for an abuse of discretion, including evidentiary rulings on expert testimony. Helena Chem. Co. v. Wilkins, 47 S.W.3d 486, 499 (Tex.2001); Broders v. Heise, 924 S.W.2d 148, 153 (Tex.1996). “The test for abuse of discretion is whether the trial court acted without reference to any guiding rules or principles.” Robinson, 923 S.W.2d at 558.

With regard to experts, those guiding rules and principles are found in Tex, R. Evm 702 which provides:

A witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue.

Id. Rule 702 requires at least three predicates: the witness must be qualified; the opinion must be relevant; and the opinion must be based on a reliable foundation. See Wilkins, 47 S.W.3d at 499; Robinson, 923 S.W.2d at 556.

In deciding whether an expert is qualified, the trial court must ensure they truly have expertise concerning the “actual subject about which they are offering an opinion.” Cooper Tire & Rubber Co. v. Mendez, 204 S.W.3d 797, 800 (Tex.2006), citing Gammill v. Jack Williams Chevrolet, Inc., 972 S.W.2d 713, 719 (Tex.1998). The test is whether the expert has the “knowledge, skill, experience, training, or education” regarding the specific issue before the court which qualifies the expert to give an opinion on that very subject. In re Commitment of Bohannan, 388 S.W.3d 296, 305 (Tex.2012). The test mandates some flexibility. In Broders v. Heise, for instance, the court held that simply because an emergency room physician was a medical doctor, he was not necessarily qualified to testify that the conduct of a neurologist caused an injury. But nor did the rule mandate that only a neurologist would be so qualified. 924 S.W.2d at 152-153; see also Roberts v. Williamson, 111 S.W.3d 113, 122 (Tex.2003)(pediatrician in that case was qualified to testify to cause and effect of neurological injuries); In re Commitment of Bohannan, 388 S.W.3d at 307 (reversing trial court’s exclusion of counselor who was offered to testify about future dangerousness only because witness was not a licensed psychologist or medical doctor).

Expert opinion testimony is relevant when it is “sufficiently tied to the facts of the case [so] that it will aid the jury in resolving a factual dispute.” Robinson, 923 S.W.2d at 556 (citation omitted). The requirement incorporates traditional relevancy analysis under Tex. R. Evm 401 and 402. Robinson, 923 S.W.2d at 556. Simply put, irrelevant evidence is of no assistance to the jury. Id.

Rule 702 also requires an expert’s testimony to be reliable. Robinson identifies six factors useful in determining reliability: (1) the extent to which the theory has been or can be tested; (2) the extent to which the technique relies upon the expert’s subjective interpretation; (3) whether the theory has been subjected .to peer review and/or publication; (4) the technique’s potential rate of error; (5) whether the underlying theory or technique has been generally accepted by the relevant scientific community; and (6) the non-judicial uses which have been made of the theory or technique. Robinson, 923 S.W.2d at 557. These factors are nonexclusive as Rule 702 requires a flexible inquiry. Id. (the factors “will differ with each particular case.”).

Subsequent case law dictates that reliability is based on more than just satisfying the Robinson factors. Gharda USA, Inc. v. Control Solutions, Inc., 464 S.W.3d 338, 348-49 (Tex.2015); Volkswagen of Am., Inc. v. Ramirez, 159 S.W.3d 897, 904-05 (Tex.2004). Expert testimony might also be unreliable if “there is simply too great an analytical gap” between the data on which the expert relies and the opinion offered. Gammill, 972 S.W.2d at 726, quoting Gen. Elec. Co. v. Joiner, 522 U.S. 136, 146, 118 S.Ct. 512, 519, 139 L.Ed.2d 508 (1997). “Whether an analytical gap exists is largely determined by comparing the facts the expert relied on, the facts in the record, and the expert’s ultimate opinion.” Gharda, 464 S.W.3d at 349. Analytical gaps arise when experts improperly apply otherwise sound principles and methodologies, the expert’s opinion is based on incorrectly assumed facts, or the expert’s opinion is based on tests or data that do not support the conclusions reached. Gharda, 464 S.W.3d at 349 (citation omitted). A court is “not required ... to ignore fatal gaps in an expert’s analysis or assertions that are simply incorrect.” Volkswagen, 159 S.W.3d at 912; Cooper Tire & Rubber, 204 S.W.3d at 800-01. But however these issues may play out, it is not the court’s role to decide if the expert’s opinions are correct, only that they are reliably formed, Exxon Pipeline Co. v. Zwahr, 88 S.W.3d 623, 629 (Tex.2002).

Dr. Funk offered opinions in a field generally described as biomechanics. Biom-echanics is “the study of the application or relation of the laws of mechanics to the body.” 2 J.E. Schmidt, Attorney’s Dictionary of Medicine, B-115 (2004); see also Eskin v. Carden, 842 A.2d 1222, 1228 Admissible biomechanical testimony bridges the gap between the general forces at work in an accident determined by physical forces analysis (whether it be ‘physics’ or ‘engineering') and the specific injuries suffered by the particular person who was affected by those forces.”); Smelser v. Norfolk S. Ry. Co., 105 F.3d 299, 305 (6th Cir.1997)(biomeehanics applies the principles in mechanics to the facts of a specific accident and provides information about the forces generated in that accident “[to] explain how the body moves in response to those forces, and thus determine what types of injuries would result from the forces generated.”).

Biomechanical experts are commonly designated when a plaintiff or defendant wish to prove that a particular kind of injury might or might not result from an auto collision at a particular speed. E.g. Nash v. Gen. Motors Corp., 153 P.3d 73, 75 (Okla.App.Div. 1 2006); Eskin, 842 A.2d at 1227. Biomechanical experts also appear in cases when a driver is attempting to prove that the malfunction of seat belt enhanced their injury from an accident. E.g. Smelser 105 F.3d at 301; Rangel v. Lapin, 177 S.W.3d 17, 22 (Tex.App.-Houston [1st Dist.] 2005, pet. denied)(“To prevail in a passive restraint products liability suit, some combination of expert medical, biomechanical, and/or design opinions” was necessary to prove defect and causation). And as here, biomechanical experts are used when the defendant attempts to demonstrate a plaintiffs injury was caused by the failure to use a seat-belt.

Was Dr. Funk Qualified?

At the outset, we dispose of one position advanced by the Appellees in this case: “Injury causation requires medical testimony from a doctor with credentials showing he is qualified to give testimony on the particular type of injury sustained.” In effect, the Appellees argue that unless a medical doctor is willing to state a medical opinion about the effect of the use or non-use of seat belts, a party fails to meet their causation burden. We think that goes too far.

The intersection of overlapping areas of expertise is fertile ground for conflict. In Guentzel v. Toyota Motor Corp., 768 S.W.2d 890, 899 (Tex.App.-San Antonio 1989, writ denied), for instance, the plaintiff took the exact opposite position as Appellees here. In that case they argued that a doctor was unqualified to express seat belt causation opinions, and that only a biomechanical expert would suffice. The court noted that the “engineers possess an extensive data base dealing with injury and cause. It is clear that their testimony could assist the jury.” Id. But the court was unwilling to restrict causation opinions only to the field of biomechanics:

Essentially then, we have a situation where a biomechanical engineer, who is not a doctor, can testify as to the cause of injuries and a medical doctor, with experience with lap belt injuries, cannot. Not only is this not logical, but it is also not within the framework of the expert witness rule. As the engineer could assist the jury with the technical viewpoint, so could Dr. McFee, with the medical viewpoint. In a case of this nature, the jury should have been presented with both.

Id at 899 (applying pre-Robinson law). That same tension is evident on this record where the treating doctors were apparently uncomfortable expressing opinions about what injuries would or would not have occurred but for the failure to use seat belts. They instead were willing to defer to a biomechanical expert.

Moreover, some prior Texas cases have allowed properly qualified non-physicians to render opinions touching upon the medical field. For instance, a properly qualified non-physieian can opine on a medical standard of care question. Bilderback v. Priestley, 709 S.W.2d 736, 741 (Tex.App.-San Antonio 1986, writ ref'd n.r.e.) (non-physician professor of biophysics could testify about “the mechanics, forces and effects of weights used in administering physical therapy[.]”); Johnson v. Hermann Hosp., 659 S.W.2d 124, 126 (Tex.App.-Houston [14th Dist.] 1983, writ ref'd n.r.e.) (former RN, based on her experience, could testify to standard of care of use of endotracheal tube). The opinion can extend to medical causation questions. Ponder v. Texarkana Memorial Hosp., 840 S.W.2d 476, 477-78 (Tex.App.-Houston [14th Dist.] 1991, writ denied) (non-physician PhD may qualify as a medical expert on the cause of brain damage). Broders itself recognizes this line of cases. 924 S.W.2d at 153-54. To be sure, the non-physician must be qualified on the very issue before the court. In Quiroz ex rel. Quiroz v. Covenant Health System, 234 S.W.3d 74, 86 (Tex.App.-El Paso 2007, pet. denied), we affirmed the exclusion of testimony from a hospital administrator on how administrative policy could have led to a patient’s brain injury. We did so because the administrator had no specific training or experience in the diagnosis of brain injuries. Id. When non-physicians have been allowed to give medical opinions, they have demonstrated training or experience on the precise question at issue. Ponder, 840 S.W.2d at 477-78 (non-physician expressing opinion on brain injury conducted research on the causes of neurological injuries and taught neurophysiology, neuroan-atomy, and neurochemistry to MDs and PhDs); Bilderback, 709 S.W.2d at 741 (witness was professor of biophysics who taught physical therapy students how to do task at issue).

Appellees primarily rely on the Texas Supreme Court’s decision in Gammill v. Jack Williams Chevrolet, Inc. for the proposition that an engineer, even if highly qualified, cannot render medical causation opinions. Gammill included a claim that an alleged failure of a seat belt led to the death of a passenger in a crash. Id. at 715. To support that claim, the plaintiffs designated Ronald Huston, a well-educated and experienced professional engineer, who had conducted research in biomechan-ics, vehicle occupant kinematics, and vehicle occupant restraint systems. He had tested vehicle restraint systems and had presented and published extensively on the topic. Nonetheless, the trial court struck his opinion that a seat belt was defectively designed, and consequently, the vehicle occupant received a fatal head injury. Id. at 716-17. The Texas Supreme Court concluded that Huston was in fact qualified to testify about the design issues and failure of the seat belt system. But in addressing his qualifications, the court noted: “Huston, too, lacks any qualifications to testify concerning the cause of [the occupant’s] death.” Id. at 719. Causation, however, was not an issue before the court as it had not been raised in the summary judgment which led to the appeal. Id. at 720.

While Appellees here reason that Dr. Funk is relatively less qualified than was Huston, and thus should similarly be disqualified from rendering any causation opinion, we disagree. The opinion in Gammill does not disclose Huston’s specific qualifications on the causation issue, nor would we expect it to because causation was not an issue before the court. We do not know, for instance, if Huston based his causation opinion on the kind of studies that Dr. Funk has both performed and relied on here. We cannot read the single sentence in Gammill as a blanket prohibition on engineers testifying to any causation issue that touches upon medicine.

In surveying how other courts have viewed this issue, the majority have reached a middle ground which recognizes that a properly qualified biomechanical expert may express an opinion as to how forces act on the human body during a collision and the type of injuries that can be sustained from those forces. Smelser, 105 F.3d at 305 (noting expert’s admission that “biomechanics are qualified to determine what injury causation forces are in general and can tell how a hypothetical person’s body will respond to those forces....”); Berner v. Carnival Corp., 632 F.Supp.2d 1208, 1212-13 (S.D.Fla.2009) (biomechanical expert may give an opinion about the energy involved and whether the energy is sufficient to have caused an injury of the type alleged to have been suffered). But most courts then draw a line preventing a biomechanical expert from testifying that a particular victim’s injury was or was not caused by the forces in that particular accident. Kelham v. CSX Transp., Inc., No. 2:12-CV-316, 2015 WL 4426027, at *6 (N.D.Ind. July 17, 2015) (expert “may testify about the forces involved in the accident and, in general, what injuries those forces were expected to cause. Therefore, he may indicate what types of injuries were likely to occur based on the forces involved in this accident. However, [he] may not testify about the specific cause for ... [plaintiffs] specific injuries.”); Roach v. Hughes, 4:13-CV-00136-JHM, 2015 WL 3970739, at *11 (WD.Ky. June 30, 2015)(noting that biom-echanical engineers are qualified to testify in general terms that “X” forces would generally lead to “Y” injuries and “Y” injuries are consistent with those the persons incurred); Berner, 632 F.Supp.2d at 1212-13 (“Dr. Williams may testify that the ‘energy on Berner’s head upon striking the floor was sufficient to have caused his mild to moderate traumatic brain injury.’ Dr. Williams will not testify that Berner has a mild to moderate traumatic brain injury—or a brain injury at all. She will not testify that Berner’s brain injury (if any) was caused by his head striking the floor.”); Wagoner v. Schlumberger Tech. Corp., No. 07-CV-244-J, 2008 WL 5120750, at *1 (D.Wyo. June 19, 2008)(“[Biomechanics experts] may, for example, testify as to the forces involved in the ... accident and how those forces may affect an individual or object; they may not express any opinions regarding whether plaintiff ... has suffered a brain injury ... or as to the ... cause of the alleged brain injury.”); Morgan v. Girgis, No. 07 Civ.1960(WCC), 2008 WL 2115250, at *5-6 (S.D.N.Y. May 16, 2008)(while biomechanical expert could testify to the “observed ... force on a human body in comparable accidents ... he may not testify as to whether the accident caused or contributed to any of plaintiffs injuries.”); Bowers v. Norfolk S. Corp., 537 F.Supp.2d 1343, 1377 (M.D.Ga.2007) (“[A biomechanical engineer] may testify as to the effect of locomotive vibration on the human body and the types of injuries that may result from exposure to various levels of vibration .., [H]e may not offer an opinion as to whether the vibration ... caused Plaintiffs injuries.”); Shires v. King No. 2:05-CV-84, 2006 WL 5171770, at *3 (E.D.Tenn. Aug. 10, 2006)(“[The biome-chanical engineer] clearly should be allowed to testify regarding the forces applied to plaintiffs head ... and how a hypothetical person’s body would respond [sic] to that force. He cannot offer opinions, however, ‘regarding the precise cause’ of plaintiffs injury.”).

In other cases, the biomechanical experts have testified to the causation of plaintiff specific injuries, but it is unclear if any objection was made to the scope of the expert’s testimony. Walker v. Ford Motor Co., — P.3d —, —, 2015 WL 5260382, at *7 (Colo.Ct.App. September 10, 2015)(“Paul Lewis, a biomechanical engineer and expert on injury causation, testified that, if Walker’s seat back had remained upright in the accident and the seat had had an adequate headrest, Walker would not have sustained any of his more significant injuries.”); Gaertner v. Holcka, 219 Wis.2d 436, 580 N.W.2d 271, 274 (1998)(“Dr. Joel Myklebust, a qualified biomechanical engineer expert witness, opined that Koldeway’s damages would have been reduced substantially had Koldeway been wearing a seat belt at the time of the accident. According to the expert, 75 percent of Koldeway’s injuries were caused by the failure to wear a seat belt and 25 percent were caused by the accident.”); Waterson v. Gen. Motors Corp., 111 N.J. 238, 544 A.2d 357, 361 (1988)(“Mr. Montalvo testified in detail concerning the injuries sustained by plaintiff. He also testified about ... the specific causes of each of plaintiffs injuries, and the specific parts and surfaces of the car’s interior with which plaintiff came into contact during the crash.... Ultimately, his opinion was that plaintiff would not have sustained any of her injuries had she been wearing her seat belt at the time of the accident”).

We need not align ourselves with any specific approach because the exact phraseology of Dr. Punk’s opinion was not at issue below. We conclude that Texas law does not per se disqualify a properly qualified biomechanical expert, who otherwise meets the requirements of Rule 702, from expressing opinions that will assist the jury in deciding injury causation questions. If the trial court had based its exclusion of Dr. Funk on the Appellees’ more absolutist contention, we think it would have erred to do so. That is to say, the trial court in its discretion might properly scrutinize how Dr. Funk parses his opinion that a particular Appellees’ injury was caused by ejection. But it would go too far to restrict all his opinions surrounding that issue merely because he does not hold a medical degree. A properly qualified biomechanical engineer, with the proper foundation and analysis, may explain why and to what degree certain injuries are more likely experienced in rollover accidents when a person fails to use a seat belt.

Appellees’ other qualification challenge urged that Dr. Funk’s affiliation with Biodynamic Research Corporation indicates a bias which should factor into the Rule 702 analysis. Evidence that an expert principally works to generate opinions for litigation is indeed one of the Robinson factors. 923 S.W.2d at 557. However, Appellees attempt to prove this bias by referencing trial court orders where different experts from Dr. Funks’ organization have been struck or limited in their testimony is singularly unhelpful in a Rule 702 challenge. By the same token, we observe that Nabors’ citation to multiple cases where those experts have been allowed to testify is no more persuasive. Whether another expert affiliated with Dr. Funk was successfully or unsuccessfully challenged does not address Dr. Funk’s qualifications or methodology. Orders from other cases would not be particularly useful unless the complete context of those other cases is known, and none is developed in the record here. Nor would we or any trial court likely have the resources to painstaking compare the facts, conclusions, methodology, or opinions generated by an expert in one case 'with that in another. Other than the relatively rare instance when our supreme court, or one of our sister courts of appeals have specifically addressed the expert before us on similar facts, with similar methodological challenges, merely reciting that another court has struck or allowed an expert is little more than a make-weight argument.

Returning to the Rule 702 framework, we first look to qualifications. From his undergraduate, master’s, and doctorate course work, Dr. Funk has an educational basis to testify to the basic biology and physics principles germane to his opinions. He now in fact teaches aerospace medicine to resident doctors at the U.S. Air Force School of Aerospace Medicine. By performing tests on cadavers in his doctorate program, he has the experience and training to testify to the kinds of injuries that the body experiences with different forces. His published works in the area of rollover accidents and the physics of ejections provide some proof of his experience to testify about what happens to a body during a rollover. His publications include actual studies on test dummies in rollover accidents that document the movements , of the body and the likely impact points, both within and outside the vehicle. Other than an opinion which might include the diagnoses of any particular Appellee’s specific medical condition, we conclude that Dr. Funk is qualified to render the opinions that he does here.

Are Dr. Funk’s Opinions Relevant?

The second requirement for the admission of Dr. Funk’s opinions is relevance. Given the trial court’s ruling that the seat belt defense was unavailable to Nabors, his opinions in the first trial would have failed that test. In light of the change in the law, we think it evident that his opinions would be relevant. If proven, they might allow a jury to conclude that Martin was more responsible for some of the other Appellees’ injuries than was Na-bors. Similarly, a jury might believe that Aydee failed to act as a reasonable person in failing to wear a seat belt, even though not required by law to do so at the time. Even the rhinors could be held responsible to that degree of care commensurate with their age. See Rudes v. Gottschalk, 159 Tex. 552, 324 S.W.2d 201, 204 (1959).

Are Dr. Funk’s Opinions Reliably Formed?

The last hurdle for Nabors is the reliability of the opinions. We address each opinion in turn.

Wearing Seat Belts or Not?

The trial court excluded Dr. Funk from testifying about the “results and/or opinions formed from his personal inspection of the seat belts in the Plaintiffs vehicle.” His observations and opinions in this regard were all germane to whether the Appellees were wearing them seat belts. It is unclear whether this portion of the order was based on the trial court’s exclusion of seat belt evidence in general, or some specific Robinson rationale. To the extent it was the latter, we find no sound basis for excluding all of those opinions.

Appellees motion challenging Dr. Funk does not specifically address his opinions on the examination of the vehicle’s seat belts. The only real question raised by Appellees at the hearing regarding the inspection of the vehicle was that it took place some three and one-half years after the accident. They suggest that the condition of the vehicle, which was stored in a legal counsel’s warehouse, could have changed over that time. Nonetheless, there is no evidence in the record to suggest there was an alteration of the seat belts after the accident. This is the type of challenge which goes to the weight and not the admissibility of the evidence. Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579, 596, 113 S.Ct. 2786, 125 L.Ed.2d 469 (1993) (“Vigorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence.”). Nor do Appellees raise any specific concerns regarding the “loading” analysis that Dr. Funk used to reach his opinion. To the extent this evidence was excluded on Robinson grounds, the trial court abused its discretion in doing so.

Injury Causation

The trial court excluded any opinion dealing with injury causation, to include the general likelihood of injury from ejection, whether the Appellees’ specific injuries were from ejection, and whether any Appellee would not have been injured if they were wearing seat belts.

With regard to injury causation, Dr. Funk’s methodology in part relied on empirical studies which attempt to show relevant injury patterns for certain types of accidents. This is a methodology typically employed by biomechanical engineers. See Thorndike v. DaimlerChrysler Corp., 266 F.Supp.2d 172, 184 (D.Me.2003). The methodology is analogous to the use of epidemiological studies in chemical exposure cases as outlined in Merrell Dow Pharm., Inc. v. Havner, 953 S.W.2d 706, 713 (Tex.1997). In those types of cases, parties sometimes attempt to prove causation by identifying population studies which show an association between exposure to a particular substance and some disease or condition (thus establishing general causation). See Bostic v. Georgia-Pacific Corp., 439 S.W.3d 332, 351 (Tex.2014). The party then will attempt to show that the particular plaintiff closely fits the same parameters as the persons and exposure at issue in the population study (thus establishing specific causation). Id. Similarly, Dr. Funk attempted to establish through studies on large numbers of vehicular accidents that the failure to wear seat belts generally results in ejection in serious rollover accidents, and ejections generally leads to more serious injuries or death. He then attempted to show how each particular Appellee fits the pattern in the studies.

Hamer does not universally apply to all tort eases where causation is an issue. Bostic, 439 S.W.3d at 347-48. Instead, it is an alternative method of establishing causation “[i]n the absence of direct, scientifically reliable proof of causation.” Id. For this accident, there were no eyewitnesses, and certainly none that could identify which of the Appellees’ injuries were caused from impact with the ground as distinct from impact with the vehicle interior. Some of the Appellees had no recollection of the accident or memory until they later awoke in a hospital. Nor would it be realistic to expect a person tumbling inside (or outside) a vehicle to identify which specific blow caused their own injuries, much less those of the other occupants. No one suggested that the accident itself could be re-created with such precision to determine the particular forces and precise movements of the Suburban’s occupants. The situation therefore lends itself to one of those situations where Hamer type studies might assist in demonstrating general causation.

One teaching from Hamer is that scientific studies must be scrutinized by the courts to ensure they meet minimal reliability thresholds. Hamer itself discussed the importance of epidemiological studies showing more than a doubling of the risk (also described as a demonstrating a “relative risk” or “odds ratio” of more than 2.0). 953 S.W.2d at 715-18, 721. A single study by itself would not suffice to establish legal causation. Id. at 718-19, 727. The study must show other indicia of scientific validity, such an adequate sample size, an accounting for confounding variables, and a proper confidence interval. Id. at 724. Courts should be skeptical of scientific evidence which is neither published nor peer reviewed. Id. at 727. “A related factor ... is whether the study was prepared only for litigation.” Id. at 726. And once the study showing general causation is accepted, the party must show that their circumstances are similar to the group analyzed in the study. Bostic, 439 S.W.3d at 347.

Before turning to the specific studies upon which Dr. Funk relied, we note a few considerations governing these studies. First, most of the authors agree that rollover accidents are complex events. Gloeckner, 2006 at p. 155; Moore, 2005 p.134 Even in a study where a specific type of vehicle was rolled over in a controlled manner—the same way each time—the test dummies in the vehicle reacted differently in different tests. G.S. Bahling, et. al., Rollover and Drop Tests— The Influence of Roof Strength on Injury Mechanics Using Belted Dummies, Proceedings 34th Stapp Car Crash Conference, Paper 902314, pp.101, 108 (1990). There are several variables which come into play. The number of quarter turns in the roll can affect the risk of injury. Moore et. al. 2006 at 134. The more quarter turns, the greater the likelihood of serious injury. Id. Moreover, the position of a person in the vehicle, and direction in which the vehicle rolls is apparently significant. For instance, when the driver’s side leads the rollover, the occupant of the front passenger seat (who is in the following or “trailing” side) have shown more serious injuries in some studies. Gloeckner, 2006 p.156.

Most of the studies presented in this case are based on data from the National Accident Sampling System/Crashworthiness Data System (NASS-CDS) which is a sampling of nationwide police reports in tow-away crashes. The database was created for use by the National Traffic Highway Safety Administration. The NASS-CDS database has information on the kind of accident (i.e. rollover, single impact, etc.) and the kind of injuries that each driver or passenger experienced. The injury data is reported under a uniform system called the Abbreviated Injury Scale (or AIS). Under that system, a reviewer identifies the body part injured and then assigns a numerical severity rating from one to six. As an example, a minor injury to the head would have an AIS-1 rating for the head. A serious injury to the thorax would be rated as an AIS-3 or higher for the thorax.

Dr. Funk initially relied on the Paren-teau and Shah study for the opinion that seat belts are 99 percent effective in preventing ejections. The study collected NASS-CDS data from 1992-1996 on single event crashes resulting in a rollover. A total of 608 rollover accidents were included which the authors described as “relatively small” sample size. The study divided the data into ⅜ to ½ rolls, ⅜ to 1 rolls, and more than 1 complete roll. The overall conclusion of the study is that less than 1 percent of belted drivers were partially or fully ejected. For the unbelted drivers, 27 percent were completely or partially ejected. Dr. Funk further supported this opinion with his own experience in staged rollovers with test dummies, where no ejection with a belted test dummy has ever been observed.

Dr. Funk also offered the opinion that 80 percent of unbelted occupants are ejected in three revolution rollovers. For this proposition, he relied on Moore et. al. 2005 and Gloeckner, 2006. The Moore study looked at NASS-CDS data for 1995 to 2003, using only rollover accidents involving 1990 or later model year vehicles. This subset of the NASS-CDS data included 4,024 rollover vehicles which were further subdivided into categories based on the number of quarter turns. The authors reference a 95 percent confidence interval. They concluded that unrestrained occupants had a greater than 80 percent chance of full or partial ejection in three revolution rollovers, compared to approximately 10 percent for restrained occupants.