 So, hi everyone. Today we're hosting Dr. Cynthia Ausley from the University of Alabama at Birmingham. Dr. Ausley is the Nathan E. Miles Endowed Chair of Ophthalmology at the Department of Ophthalmology and Visual Sciences where she also directs the clinical research unit. She obtained a PhD in experimental psychology with a focus on visual perception from Cornell University, which she followed with, she followed this degree with a postdoctoral fellowship in visual psychophysics and aging at Northwestern University. She also later obtained a Master of Science in Public Health from UAB. The core of Dr. Ausley's research lies very close to the patients and to their experience of visual changes that, and in that way she's rather unique in the field. Her research considers several aspects of functional changes and how we can intervene to mitigate them. These include functional changes that are associated with aging and ocular diseases. She's also monitored how these changes affect the quality of life of those affected. She has also given specific attention to vulnerable and underserved populations in ophthalmology. I'll mention a work on functional biomarkers in age-related myculele degeneration, which is very far-reaching and influential. She has shown that rod function was particularly impaired in AMD and that delays in rod-mediated dark adaptation could be used as an early biomarker of incidence of AMD. She'll talk more to this later in her research talk, which is at one, which I very strongly recommend for you to attend. As part of her research, she has also explored the relationship between vision and driving with the goal of translating some of her findings into public policies. I'm very excited to hear her talk. Tell us more about this. Please join me in welcoming her for this talk. Thank you. Thank you so much for inviting me for these two talks today. Today, this morning, I'm going to focus on vision impairment, focusing on older drivers. And the reason our research program focuses on older drivers is that vision impairment is so much more prevalent in this population. You can have vision impairment, of course, at any age if you're a driver, and we have done some research on older drivers, younger drivers using bioptic telescopes, people who have hemianopia. But today I'm going to be focusing almost entirely on older drivers. These are my funding sources. So the two topics I'm going to address today is first looking at the question of how we can visually screen for motor vehicle collision risk at motor vehicle administrations. As you know, in all states, in order to get a license, you have to have visual acuity screen. I'll talk about this more in a moment. But the question there's there's really very important questions as to whether visual screening is really worthwhile in terms of meeting a safety goal, making sure you're minimizing collision risk. The second topic I'm going to address today is using naturalistic driving methods. This is where equipment is actually embedded in older drivers vehicles, their own vehicle and then they drive around. It's video vehicle kinematics and we can get really a hands on really objective method about how they're driving and looking at this in terms of collision risk. So first, looking at vision screening. So first I want to point out that there's really many methods for studying driving particularly older drivers, and Jerry McGuinn and Joanne Wood. And I kind of summarize this literature in the survey of ophthalmology, but essentially here are the major ways you can study driving and particularly from a visual standpoint. So you can look at driver safety motor vehicle collisions. And these are usually expressed as rate in terms of how, how many collisions you have per person miles of travel or person years of driving. And in these situations, you get accident reports actually from the state. It's sort of like an objective record sort of like a death certificate and it has, I'll show you an example in a moment, all the details if you've ever had a collision, you've been able to see one of these reports from the state, if in fact the police officers reported it to the state. The second way we can study older drivers is looking at their driver performance actually looking at behaviors and vehicle kinematics when a person operates a vehicle on a roadway. And you can look at this both in open and closed road roadway designs. This is a very popular technique in some parts of the country. And I'll get back to that in a moment. Another way we can study drivers is sort of analogous to patient reported outcomes, we can use driver reported outcomes, meaning questionnaires. And these are asking older drivers. Please self report your types of driving experiences, your attitudes your beliefs where you think you're having problems where you're not having problems. And these of course are collected through structured questionnaires and there's many of these questionnaires out there. And then a final way we can study driving is using driving simulators. And it's important to keep in mind that what these are scenarios scenarios and driving tests that are presented via visual display. And then they're designed as laboratory representations of what's going on in the real world. And I'll talk a little bit about the strengths and limitations of this approach as well. So let's get back to visual acuity. So visual acuity is a screening requirement and all states in the United States and many countries throughout the world. In most states, the screening, the minimums acuity you can have is 24 or 40, sometimes 2030, although there are exceptions for example in my state you can drive at 2060. Many states have visual field requirements and they're actually in their legislative status. Their variable and extent, their variable and how they measure it. And in fact, even in some states such as Alabama we don't really screen for visual field there's a statute about it but it's never screened for. So in terms of getting your license and going back in for rescreening the timing of license renewal really varies among states. In some states it's actually limited by age in other words you don't start having to have visual acuity screened again until you're say 60 or 70. In some states they do it randomly with those age groups, but in some states, every time you go in for a license renewal, they screen visual acuity. And what the real research issue here is, decades of research, literally decades of research have really failed to find a relationship between visual acuity and safety. Most of these study designs have been weak they have not been population based they have not been using what we would consider the clinically accepted, acceptable valid reliable vision tests. So, why was 2040 accepted by so many states. This is basically because 2040 as deemed by the Federal Highway Administration, part of the US Department of Transportation. It was selected years ago as because this is the ability to read road signs, for example on an interstate or a state road, and an appropriate visibility distance so that you can still stop the vehicle. That's why we ended up with 2040 we didn't end up with 2040, because there was safety data motor vehicle collision data suggesting that this is where your collision rate jumps up to have worse than 2040. So, vision is obviously very important for driving so why is really there no association between visual acuity and motor vehicle collisions. One reason and there's probably many reasons for this drivers with poor acuity in some cases stopped driving, either voluntarily or involuntarily perhaps their physician, their ophthalmologist or optometrist reports them to the state and then the license is eventually stopped. There may actually be an association between acuity and motor vehicle collision risk, but it has a minor role in the sense that it only occurs in very severe deficits, for example, worse than 2200. So, to say that acuity has nothing to do with driver safety is a little bit incorrect, it's because we really don't study drivers who are say have 2200 2500. The thing they also keep in mind is the collisions really are multi factor factorial in their causes many things can cause collisions other medical conditions, for example, dementia cognitive impairment, environmental factors on the roadway and also vehicle factors. In many cases, if I'm the driver and I have a collision it's not because I did anything it's because the other driver or drivers did something. And so, finally, it's important to remember that visual acuity is really in my mind in an adequate representation of the visual skills you need for driving. It's also important for example peripheral vision, visual search, visual attention, motion perception, contrast sensitivity, all these things seems like seem like they would be important. And seeing having excellent spatial resolution may be important for reading a sign at a distance down the road, but it's not really from what the research suggests it's not really important for not running into a large object in the roadway, which is dominated of course by low spatial frequencies. So, many people think that if we identify visual impairment risk factors, for example, in population based studies or convenient samples that they would be good screening tests to be used at the DMV. And I think this is basically what the study I'm going to describe to you has looked at, just because you have an elevated risk doesn't mean that it would be a useful screening test. As I already mentioned vision impairment is much more prevalent in older drivers and that's why we focus on it. And so no study prior to ours using a population based approach has effectively addressed whether different types of vision screening could be used to identify crash prone older drivers in other words drivers, not who had a history of crash involvement, but who are threats on the road, going into the future, prospectively. So here's our study design. We study 2000 drivers in North Central Alabama. And at baseline what we did was we used a number of different types of vision screening tests. We also confirmed their driver status looked at their driving exposure and we'll get back to that in a moment. Then over the subsequent three years we collected at the very end of that period. We collected their motor vehicle collision data for that three year period from the Alabama law enforcement agency which in Alabama is the state agency that where police report a collision. The accident report is filled out and it's filed there and you can actually in most states, I would say in many states actually get these data from the state with the participants permission. So every year period we wanted to make sure people didn't stop driving or die, or move to another state so they won't weren't having collision exposures in Alabama so we found them every year for three years to me to make sure that they were still driving. So the source population is Jefferson County, Alabama as I mentioned this is in North Central Alabama. Everybody was 70 years old or older we're focusing on this range, because according to the US Department of Transportation and National Highway Traffic Safety Administration. This is where the collision rate starts to go up in older drivers. It's, it's not quite as high as the 16 to 25 year old drivers but it starts to elevate and starts approaching their collision rates. We randomly selected from a list of persons from a direct marketing firm, and then we confirmed it that they were actually licensed in Alabama. We could not use the state motor vehicle record the state licensing data to recruit the patients because this would be a violation of privacy but we could use this marketing firm where we could identify these are basically people who who've had credit of one type or another over the previous years, but then we could confirm that they were actually still licensed in Alabama that was allowed. Of course they had to speak English. They were community living they weren't living in nursing homes, and they had to have driven in the past three months. And as I mentioned we enrolled 2000 people. So in terms of the baseline screening tests. We looked at many of the popular candidates that have been looked at in the literature and we chose these because there was some suggestion literature. They might elevate collision risk in older drivers. We of course we used visual acuity, because this is what the state uses we also looked at contrast sensitivity visual field sensitivity using a driving visual field which I'll mention in a visual processing speed, which is a computerized test and we also used a paper test for this. And this this looks at how quickly you can process information. When two targets are presented whether you can tell them apart and also the impact of distract distract distractors on that. So it's basically in terms of milliseconds how quickly can you tell two things apart. And we also looked at visual spatial skills because the literature has suggested that these might be important. Now when we looked at the driving visual field. You didn't, for example, use for example from a Humphrey field analyzer the 24 dash two or the 30 dash two. We actually looked into the literature, and we identified, and we also took a picture and a vehicle of the part of visual field that you actually use when you're looking out your windshield. And this goes to 15 degrees above fixation. It goes 30 degrees below if you also have to pay attention to the dashboard, which in many cases is important. And because of the limitations of the Humphrey visual field the only one out 60 degrees. So that's the area of the visual field we actually looked at. We also previously in the 90s we developed a driving habits questionnaire and the purpose of this questionnaire is to assess driving exposure so we didn't have objective driving exposure information, but we did get self reports of weekly mileage so we could convert it to annual mileage because keep in mind we're trying to understand motor vehicle collision rate per person miles of driving. So one of the descriptive results. The mean age was a little over 75. The racial groups were very typical of our population in North Central Alabama about 80% white 20% black. These were drivers about half drove daily about 75% drove at least five days a week. And these drivers also had normal cognitive status. There might be some bias you may not volunteer for a driving study if you suspect you have cognitive problems, but basically in this study cognitive factors are really not a confounding influence of a collision rate. So in terms of the vision impairment, 8% had visual acuity worse than 2040. So how could this be well in Alabama we don't screen for visual acuity so the only way if you had worse visual acuity if you wanted to be. If you wanted to drive you could still do that 7% had impaired contrast sensitivity 11% slowed visual processing speed, about 15% had impaired spatial cognition, where you had trouble telling whether to job objects one was in front of the other and the basic spatial configuration was, and we have no normative data on visual fields or motion perception, simply because we, we used quartile splits. So we had 2000 drivers in total over three years they had 359 collisions 16% of the drivers experienced one or more collisions during that period so you can get a feeling for the kind of numbers. So just to keep in mind collisions are what statisticians would cause, call rare events. They're not common events. So the analytic approach we use for using vision tests to identify collision involved drivers we use logistic regression we use to estimate the area under the curve for each vision test we also use clinical cut points, as well as basically empirically based cut points based on the distributions in in from our older drivers. We use receiver operator characteristics to identify optimal cut points so that we could specify sensitivity and specificity for each test. And we use Poisson regression to look at the rate ratios for every test in other words understanding whether it elevated risk. So the question we're looking at as well statistically significant associations between a vision test and motor vehicle collisions lead to high sensitivity and specificity. So here we use the clinical cut points. And so if we look at all these tests you can see they actually have very poor sensitivity and specificity if they have high specificity we have poor sensitivity. We did see, we did not see significant associations for unadjusted rate ratios for all the vision tests adjusting for all the things that are listed on the slide, but with adjustment for many confounding variables, significance did disappear. So we're not finding any risk with clinical cut points. However, when we use the optimal cut point based on the distribution of the data. Note sensitivity and specificity is still poor. However, we found significant associates associations for the unadjusted rate ratios for all the vision tests except visual acuity that repeats itself from the literature, but after adjusting for confounding variables. We see significance for contrast sensitivity slowed processing speed, spatial perception and visual field, but these risks, as you see they might be statistically significant, but they are low. But again, keep in mind there are many causes of crashes. And so this is very typical of what we see in the literature flow population based studies, as well as for convenience sample studies. These risks exist, they're real. However, they're low. We also used any combination of these tests to try to beef up the risk ratio, and using any of these tests together or in combination, it didn't really change a whole lot it was about to. So in summary, even though we found significant associations between vision impairment and crash involvement, none of the tests had good sensitivity and specificity. And typically in public health, when we talk about screening at a population level we're looking for sensitivity at about at least an 80% level or higher, and we certainly did not find that. As mentioned, we did see elevations in risk for a number of visual field tests as I've already mentioned, but again, visual acuity was definitely inadequate was not a risk factor. So, a continuing problem that exists in the field is that, given if you look at the literature on vision impairment and risk factors. What happens is there's an advocacy for using these risk factors, which happens when ophthalmologists and other researchers also neurologists read the literature, and the state legislatures of the policymakers contact them and say, Well, all these things are risk, why don't you consider screening for these at the population level. But as we can see here, these are really tenuous and I would say questionable recommendations that are passed on to medical advisory boards, because when we look at sensitivity and specificity, it would be basically a poor investment public health dollars to screen for these vision tests. Okay, so I'll go on to the second part now, I just need to drink a water here too much play. Okay, so natural. Sure, yes. The last slide. Oh, sure. Absolutely. Sorry. So naturalistic driving techniques. So, in using these techniques, as I mentioned, personal vehicles of drivers are installed with equipment, measuring kinematic variables, also location, also multi channel video. After these devices are installed on the vehicle in the studies the drivers and drive their vehicles for an extended period of time, where objective data can be collected. What can you measure you can measure a variety of things, depending on how long, you're only measuring for a couple of days, the probability of seeing a crash is probably very unusual. But if you're measuring for a longer period of time, months or years, you could see crashes or something referred to as near crashes where they don't actually have a crash, but almost it happens. But you can actually measure rapid accelerations and decelerations, other driving behaviors such as turning and other types of things. This can be stored and this is an illustration of the Virginia tech model. All these can be stored to a hard disk which is stored in the vehicle and then you can pick up the hard disk and then extract all the data. So Virginia tech was really the organization that pioneered this work, first with the hundred car study which some of you may be aware of, but also what what is called the sharp to study, which involved almost 4000 drivers at several locations in the United States and I'll mention that in a minute. We also use this technology in a study I'm going to describe to you at UAB called the VIP older driver study. The advantage of naturalistic driving. Well, first of all, in most studies whether they're convenient samples or population based studies on crash involvement. The crashes are defined by accident reports from the state. This is an example from Alabama, but accident reports across states look very similar because there's certain data elements that the US Department of Transportation requires that are on these accident reports. The problem with these reports is not all require crashes are reported to the police, this is only filled out for police officer comes to the scene. They're also prone to bias there's some evidence that when drivers are older, the police officer is less likely to site them and actually report, fill out complete an accident report. Driving exposure is defined by self report in these studies and it's not objective. Another advantage of naturalistic driving is that it's direct objective study of driving behavior as it occurs and every day life. It's not interpreted by a driving rehabilitation specialist. These people are, they're usually called CDRS is they're often occupational therapists, and as illustrated in the picture here they go out with a driver, and they usually have a checklist or they have some sort of set of criteria they used to to evaluate the driving behavior. It's also not a valued on the actual, it's evaluated an actual roadway, but it's on a pre specified course that it's usually chosen by the researcher or the CDRS, the rehab specialist. Whereas in naturalistic driving, the driver chooses their own roots in the course of everyday life they drive when and whenever they want. So that that's an important distinction. Another advantage is that it's driving in naturalistic driving is not dependent on the self report by the driver, the driver might actually say well, I'm actually a good driver, but what we can do is actually measure the objective behavior. And then finally, we're not dependent on a driving simulator. Now, driving simulators have very important advantages and I know there's a group here in, I believe they're in psychology or brain sciences that do do use driving simulators, and they have distinct advantages, because they really create a great environment for extent experimental stimulus and response control. It's also a safe environment, no one's going to get hurt now maybe they might develop some nausea for being in the simulator, but it's a safe environment. The disadvantages, even though in the most sophisticated simulators, the visual displays are as good as they can be their obvious oversimplification of the complexity of the real world driving environment. Drivers are also well aware that they're not really driving. So they don't have to have a lot of, they don't basically have the same risk perception they have when they're driving actually on a roadway. So it's important to keep in mind why naturalistic driving would be important. So the 100 car study was the first naturalistic driving study. And as I mentioned, this was done by Virginia Tech. And this is just an illustration of their first venture into this area. It was basically just a proof of concept study was 100 vehicles of ordinary drivers they didn't seek out anybody with specific medical conditions they just found 100 people who would enroll in the study. As mentioned, it was an unobtrusive data collection system. There were no instructions to the drivers they drove about a year, and they drove all together about two million vehicle miles of drive drive 200 vehicle miles of driving. And the reason this is a really important proof of concept study they generated many extreme cases of driving behaviors. And you can actually for a long time they were available on YouTube you could probably still look them up and watch these and they basically blank out the face of the driver. The sharp to study basically came out of the hundred car study, and it was a sample from six different sites sites. They tried to do population based screening but in in the end, they also used advertisements. These are some of the criteria, the, the drivers in the study drove up for two years with the equipment in their car. And as you can see here about 3500 drivers from age 16 all the way up to 98. This data is publicly publicly available for anybody who's interested in vision and driving, and you can get it through Virginia tech. Prior to driving prior to driving they also did a large battery of tests and they did include vision as one of the things they measure they measured various vision tests and we'll come back to this. The problem with the sharp to study is the vast majority of people had good vision, even the older drivers. So if you're, if you're like me and like my research group you're interested in visual impairment risk factors for crash involvement. This study has some limitations. Identify risk if you don't have people with impaired vision. And the other problem is they use met many choices for vision tests that many researchers at least in vision science would not consider the most reliable and valid to use. In addition to that, we did a study called the VIP older driver study. And our major reaction is we wanted to include people who were visually impaired in other words people who had various eye conditions that cause various vision impairments yet we also wanted to enroll normally cited older drivers. In other words we wanted to overcome what we viewed as a major problem of sharp to for understanding vision and driving. So this time we conducted the study ourselves right in Alabama using the sharp to devices. So we recruited patients who were seen at the Kelly and I clinic that's the academic clinic of the UAB department about themology. And as you can see here was a vivid brochure we sent this to people we identified through that we identified them through the clinic. You'll also notice the huge honorarium. Keep in mind these people were going to be observed in their own personal vehicles for six months. So we needed to make an honorarium you know consider that to a clinical trial where you might come in three times a year for an hour. We wanted to make sure we reimburse them for appropriately for the time and dedication and we're giving us. The same protocol went like this. We enrolled about 156 drivers. We focused on people age 70 and over at enrollment. We did the baseline vision battery which I'll describe in a moment which will be very similar to the one I previously described for the 2000 person study. And during that visit is when the. The desk the driver acquisition system was actually installed in their vehicle. We made sure it was working correctly and then we sent them out and they lived their life for six months. We call them a few times to see how things were going. We also had. We checked on this and the device had a health check about every two weeks to make sure it was still working. So if the device was not working. We basically could have them come in or go to their home and replace the device at the end of the six months. We confirmed what their vision was like just to make sure that somebody didn't have an acute event and their vision suddenly got worse and the desk was being installed. So we focused on we focused on on many things. That's not mine I think I have it on silent. We, we focused on many things in this study but what I'm going to describe to you is our study of examining the association in vision impairment and the VIP study and crashes and near crashes. We published this last fall in the Journal of American Medical Association ophthalmology. So in terms of the sample demographics, most of the people were in their 70s and 80s, although we had a couple in the 90s. Again, the same distribution, about 20% black, about 80% white. Men and women were equally represented. They had a better range of education than sharp to their cognitive status was also normal and they were not depressed depression can also cause problems and driving. And you can see here examples of the different types of vision impairment. Excuse me different types of eye diagnosis we found in our sample. Our sample was not designed to look at the association between eye diseases and collision involvement or near collision involvement. That would have taken a very different types of study design with many more patients what we're more, what we're focused on is the relationship between vision impairment from these conditions and crash and near crash involvement. And as you can see here, the middle column is in the last column is percent, and you can see that we're experiencing. Basically, we do have vision impairment in our sample. And we only had three drivers with visual acuity worse than 2040 so probably not going to be able to use the sample to look at visual acuity using naturalistic driving techniques, but I'll just point that out. I think people as I mentioned early screened themselves off the road are screened off the road by their, maybe healthcare provider, or just for some reason the family asked them not to drive. So here we'll look at the age adjusted associations between baseline visual function and at fault and near crash involvement. Basically what we found very similar to the on the accident reports study we confirmed using naturalistic driving techniques that contrast sensitivity death deficits and slowing in visual processing speed. Also impaired motion perception we looked at in this study, and that also was associated with collision involvement. Again, I'll emphasize except for slowed visual processing speed which is actually the ratio of five which is quite high. These risks are typically low, but they statistically exist. So in summary using naturalistic driving methods we identified three types of vision impairment, as I just summarized the strengths of this approach this approach was that we avoided the biases of vehicle accident reports. We used a combined outcome of crashes and near crashes. Early naturalistic driving studies and older adults were only defined by rapid acceleration and de acceleration they weren't not defined by video. So this is real real clear step forward for our study. The limitations it's a relatively small sample. We compared it to the accident reports study with 2000 drivers and paired visual cutie could not really be a value way. And the study as I mentioned was not really designed to understand crash risk by ocular diagnostic diagnostic category. But naturalistic driving studies, like I've just described, I think is a very exciting method. And I think these methods going forward more and more people more and more researchers around the country and also in other parts of the world are using these methods to understand how older drivers obtain visual information from the driving environment, and how that impairment interferes with this process of driving. The vision screening as mentioned earlier and answer to one of the questions may be effective for subgroups of drivers with a high risk of collision involvement. But it, but at vision screening at a population basis, based on our study is not really recommended. So current vision acuity screening laws may unduly penalize older drivers by removing people from the road, who are not really unsafe. Consider the negative impact of driving cessation on older drivers, one of the groups, one of the very important, one of the big consequences of forcing somebody to stop driving and over three or I think about three or four prospective population based studies. So driving cessation leads to incident depression. And so it really affects quality life in an important way. So going back to the naturalistic driving study. What I want to do is show you, I can find the cursor. Okay, so let me set this up. This is a gentleman in the VIP study. The, the technology at the time was from 2009. So the video is grainy. The types of naturalistic driving we do now has much better quality video. But this is an example of a crash. And I'll give you the prediction actually tell you ahead of time, it involves a person they were not injured. However, it did involve a crash and I'd like you to see it. I just want to make sure you understand that we have the permission to show these slides for educational purposes. He's at an intersection in Birmingham, and he's just waiting there at the red light. And any moment now, he starts to move, and he runs into a person. So that's an example of a crash. And interestingly enough in the case and he looks flabbergasted, and she waves him on so she said she wasn't hurt she basically walked into the vehicle as it was moving. She didn't have vision in his right eye, which may have contributed. Here's an example of an encounter. Here's an example of somebody who's using a cell phone older lady was using a cell phone, and she almost has a near crash. And if you look over in the top right. There's two lines of traffic she's in the left lane, and there's a car off in the side of the road trying to pull in, and then she's playing with her cell phone you can, if she was looking at the road she would see that person. However, because she's looking at the cell phone she actually misses it. So watch closely in the upper right of vehicles going to come in from the right. There it is. And she with a funny part is even though she realized that was not a good thing to happen, she continues to use the cell phone. She continues to use the cell. And I thank you for your attention. I'll try to talk directly. Right. Yeah, thank you so much that was really awesome work. And just tons of interesting thoughts about it, but did you there. Do you look at like cell phone use as a risk factor and how that compares to some of the visual impairment. The different how you know those were relatively low risk, imagine cell phone risk might be much higher. Yeah, that's an interesting question with 15655 people really didn't have statistical power to address those types of questions I think that question is fascinating. And the question that we did look at using sharp to data wasn't with the VIP data set that was much larger data set we were studying in that sample there were about 700 people who were aged 70 and over. And that data set were many types of ways driving could be distracted. Eating something. It could be putting on eye makeup, it could be doing something in the side seat or trying to attend to a child or backseat as well as use cell phones. And what we found in that study is all these distracted driving behaviors, if you took them collectively to not elevate collision risk. However, the cell phone. Did was about four times the rate of collision involvement in that large study so I think the cell phone uses is just a really fascinating topic and I think many people have used simulators. Also other types of population based studies where they use accident reports and they can tell the time the call went in on the cell phone and they put the two sources of information together. But I think really the naturalistic driving studies could really address that question. Okay. Oh, I just went here. Obviously, the visual acuity wasn't a big factor. With visual field boss. There's quite a bit of problems. Should we be springing them for this in my population, younger population or he wants we're having crashes. This visual field is patched visual field boss, they're not seeing the strengths of their hearts. And that's hard to evaluate that. I think, I think in the clinic, those are very important screening methods, because as they're optimologists, you need to make recommendations to them about driving. The problem is there's not a lot of what I would call highly quantified information from the literature says, well, how big does this guitar have to be or how much the periphery has to be involved before they're more dangerous. So I wish I could answer your question. I encourage you to screen all your patients for that clinically, but a population line what's not going to be useful clinically, I think it could. Dr. I was a Robert Christians, not been involved in working with additional impaired. Oh my gosh, it's probably 45 year project 45 years residency. And I want to thank you so much for the work you've done. This is not a popular thing to be looking at. People perceive driving as right. Not a privilege. Medical advisory board stresses that is a privilege drive, not a right. So your work is wonderful. You've spent years doing this. Thank you very much for doing it for your clients are dedicated yourself to this approach to helping us understand this. I think that's what my question is, is that you mentioned one of the important things is visual processing speed or visual processing ability. Is that relatable to anything we see clinically. We don't normally test visual processing ability and it seems to want to be one of the chief factors that you're looking at. That's a question. Thank you for earlier comments. It's not, it's not evaluated. It's, it's more so evaluated neurology where you see cognitive factors, but you can have slow visual processing speed and not have something that seems to be common with growing old. The brain moves more slowly. I can, you know, I don't think it would really be appropriate for an ophthalmologist to screen for that. However, what many states have done and we did this for over 25 years at UAB, it's a driving assessment clinic where if an ophthalmologist, an officer, even an internist in any, even had referrals from neurological surgery, where they noticed that their patients might have deficits that impact driving them refer them to the driving rehabilitation assessment clinic and the OT and the certified driving rehab specialist would evaluate them. Those in clinic and also on road, then make a recommendation back to a physician. And in those types of clinic clinics, driving assessment rehabilitation clinics, visual processing speed is, I would say, almost always assessed. This is really one of the most potent visual cognitive risk factors and older doctors for collision health. Thank you so much. We do have an excellent vision rehabilitation program which analyzes things associated with this facility and they do an excellent job with your question. Thank you. I was just wondering about the implementation of your type. Driving type on a cost basis for me, I don't know what you're trying to do this. I don't know. Everywhere, how that works, versus maybe screening people as a guide and specialist. That's my question. It seems a great response. I'm sure so I'm supposed to be repeating the question. Sorry. So this is a question. What are the financial implications of doing much mostly driving type assessment. It's very expensive. We have four to five channel video. Many times we had to go out and fix the vehicles, the video got those or the other kinematic variable technologies. We're working right to give you an idea to spend studying 156 drivers, he studied more than crashes crashes. It was 3.5. So it's a very expensive approach, the sharp to study, which I mentioned was on the 35 drive 35 underdrivers on like six locations. I mean, billions and billions, billions of dollars. Again, US Department of Transportation, so using it as an assessment tool. The way it exists today would not really be recommended. However, for doing studies, if you can identify resources, this was funded by the National Institute. If you can get them funded, it would be very worthwhile because it provides a level of data you just don't need to get from all the other techniques. You can put in because it's, you know, truck down the cost. If you're studying, say that something that's less costly might be a good thing like a driver, specialist at a certain age, you know, kind of test people. Absolutely. I think the way most clinics work is that when they refer to the patient is exactly that type of person you have specialists and occupation therapists who actually does a clinic assessment. There are some risk factors that are important for collision involvement, but then they also take them on the road and use a variety of things checklists. They're mostly in the form of checklists with like scales, and they do their evaluation. The problem with basing a licensing decision only on that. This is usually a short snapshot of driving. It might be an hour. Some clinics might do, you know, three to four visits. It really just depends on how the clinic is set up. The other challenge in the clinic is that driving is not considered an instrumental activity of daily living by Medicare. In some states, they manipulated it such that it will be reversed, but in most states, it's a cash operation. And that really prevents older drivers who have various medical conditions, particularly visual or cognitive impairments, even motor impairments, are going through these assessments because they pay for themselves. I think the crisis is coming tonight, and we're privy to a lot of people's clinics. It can vary anywhere from like 250 to 500 to 600. For an older adult that can be very happy. I think it's unfortunate because of having seen a couple of kids that were close to our family actually killed by drivers older drivers. I feel that more people, and I'm getting to that age myself that 70 or something should be retested, just like retested when we're 16, 17 to get that license. Yeah, your point is well taken. We did a survey in the state of Florida, asking for mandatory, or did not have mandatory visual acuity screening until maybe 10 years ago. They instituted it. Before they did that, we did a survey and asked them whether they would mind coming in for a visual acuity screening test. And the vast majority were fine with that. So there's a lot of controversy about it. There's controversy from a public policy standpoint of affording state affording to do all that for all the older drivers people live a long time now. And then there's basically from everything that told you to change to that visual acuity is not really the asset test. No, it's not. I think that's right. If you look at any methodologies, testing glare and it's glare tested in the vision we have. Because then we look at evaluating its ability glare and do the driving assessment clinics use disability glare testing. I think some of them do. I think it depends when you come from some of the driving assessment clinics. I want to focus on cognitive issues and visual issues. When we had our clinic, we had to close it recently. But when we had our clinic, we did evaluate that. One of the problems that you can look at the large studies done over, say the past 20 years on visual, that's a visual function that elevating crash risk using accident reports right now. And the glare itself doesn't isn't really the asset. It is the asset. It causes a problem for overdrivers. I'll tell you that in questionnaires, if there's some reason studies. It's not really reveal risk. However, contrast sensitivity, which is also often the way to measure disability there is revealed. For example, we did a study in the early 2000s, looking at people who underwent cataract surgery and people who had cataracts that chose not to the mid 90s. And we found that cataract surgery actually reduces collision risk and adults age 16 and over. The primary reason that this was the case is the improvement in contrast sensitivity. So I can't really answer your question about glare it's kind of a weirdness in the literature, but contrast sensitivity is important. And it's usually how we measure later. I have one last question. So you mentioned, you know, when it comes to collisions and the ones you were able to partner with this certain times of the day where they were more likely to happen. Was there any possible association with specific type of visual. So, you know, instead of, it was stopping so much, you know, if you're reducing, that's just selecting a good one. So the question is, do the collisions we see in any of these studies tend to occur at a certain time of the day, and would it be appropriate to recommend for example day driving. So, even like many states to have those sorts of regulations for day driving certain types of individuals, but not this vision problems maybe cognitive issues. It's really interesting when you look at the collision furniture, typically you're focusing on age 70 above almost all the collisions are during the day. And think about the left side of older adults, they're active during the day, they're not going to work, they're probably not staying without late at night. And so, and the really fun time addressing the question of our visual dispatchers at night different. The first thing that happens with older drivers is the first thing they start self regulating on their own is not driving. They start to minimize it and some older drivers they stop it, and they drive during the day. And because of that, it interferes with the ability to judge that question. But a important thing I haven't really discussed you have done a lot of research on self regulation self regulation and older adults is a very important and they do do so once they don't worry about. Thank you very much.