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Implantation and maintenance of a permanent cardiac pacing system in children remains challenging due to small patient size, congenital heart defects and somatic growth. We are developing a novel epicardial micropacemaker for children that can be implanted on the epicardium within the pericardial space via a minimally-invasive technique. The key design configurations include a novel open-coiled lead in which living tissue replaces the usual polymeric support for the coiled conductor. To better understand and be able to predict the behavior of the implanted lead, we performed a radiographic image-based modeling study on a chronic animal test. We report a pilot study in which two mechanical dummy pacemakers with epicardial leads were implanted into an adult pig model via a minimally invasive approach. Fluoroscopy was obtained on the animal on Post-Operative Days #9, #35 and #56 (necropsy). We then constructed an analytic model to estimate the in vivo stress conditions on the open-coil lead based on the analysis of orthogonal biplane radiographic images. We obtained geometric deformation data of the implanted lead including elongation magnitudes and bending radii from sequenced films of cardiac motion cycles. The lead stress distribution was investigated on each film frame and the point of maximum stress (Mean Stress = 531.4 MPa; Alternating Stress = ± 216.4 MPa) was consistently where one of the leads exited the pericardial space, a deployment that we expected to be unfavorable. These results suggest the modeling approach can provide a basis for further design optimization. More animal tests and modeling will be needed to validate whether the novel lead design could meet the requirements to withstand ~200 million cardiac motion cycles over 5 years.

This paper discusses the technical and safety requirements for cardiac pacing of a human fetus with heart failure and hydrops fetalis secondary to complete heart block. Engineering strategies to meet specific technical requirements were integrated into a systematic design and implementation consisting of a novel fetal micropacemaker, a percutaneous implantation system, and a sterile package that enables device storage and recharging maintenance in a clinical setting. We further analyzed observed problems on myocardial fixation and pacing lead fatigue previously reported in earlier preclinical trials. This paper describes the technical refinements of the implantable fetal micropacemaker to overcome these challenges. The mechanical performance has been extensively tested to verify the improvement of reliability and safety margins of the implantation system.

We are developing a cardiac pacemaker with a small, cylindrical shape that permits percutaneous implantation into a fetus to treat complete heart block and consequent hydrops fetalis, which can otherwise be fatal. The device uses off-the-shelf components including a rechargeable lithium cell and a highly efficient relaxation oscillator encapsulated in epoxy and glass. A corkscrew electrode made from activated iridium can be screwed into the myocardium, followed by release of the pacemaker and a short, flexible lead entirely within the chest of the fetus to avoid dislodgement from fetal movement. Acute tests in adult rabbits demonstrated the range of electrical parameters required for successful pacing and the feasibility of successfully implanting the device percutaneously under ultrasonic imaging guidance. The lithium cell can be recharged inductively as needed, as indicated by a small decline in the pulsing rate.

Several studies have been made to develop different versions of new leadless, permanently implanted small electronic devices that allow to be injected into muscles (BIONs™). Their circuitry should be protected from body fluids by thin-walled hermetic capsules of rigid and brittle materials such as glass or ceramic to include feed through for their electrodes. These packages experience repetitive stresses due to the muscle contraction from their excitations. This study provides a worst-case analysis of such stresses and methods to test and validate devices intended for such usage, along with the failure analysis and remediation strategy for a design that experienced unanticipated failures in vivo.

The role of age (youth and driving inexperience) and alcohol as major risk factors in traffic crash causation has been firmly established by numerous studies over the past 50 years. Less well established is how the two variables interrelate to influence crash risk. Some investigations have hypothesized an interactive or synergistic effect in which young drivers with less experience and a greater tendency to take risks are more adversely affected at lower blood alcohol concentrations (BACs) than are older drivers. The evidence for this hypothesis is mixed. Resolution of this issue has important implication for developing countermeasures directed at the young driver crash problem.Case control data previously collected in Long Beach and Fort Lauderdale were reanalyzed using a more sensitive method for detecting interaction effects than used in the original analysis. A conditional logistic regression analyses found a highly significant agexBAC interaction (P.0001) involving differences between drivers under 21 and those 21 and older.The results clearly indicate that positive BACs in drivers under 21 are associated with higher relative crash risks than would be predicted from the additive effect of BAC and age. It is likely that two mechanisms are operating to cause the interaction. First, it seems likely that the crash avoidance skill of young novice drivers would be more adversely affected by alcohol due to their driving inexperience, immaturity, and less experience with alcohol. Second, drivers under 21 who choose to drink and to drive after drinking probably have pre-existing characteristics that predisposed them to risk taking and crash involvement apart from any increased vulnerability to alcohol impairment.The results support increased enforcement of zero-tolerance BAC laws for minors.

Introduction In 2004, Washington State applied NHTSA's High Visibility Enforcement model used in the Click It or Ticket seat belt campaign in an attempt to reduce unsafe driving behaviors around commercial motor vehicles (CMVs). The program was called Ticketing Aggressive Cars and Trucks (TACT). This paper details the methods used to evaluate the program's effectiveness and the results of the evaluation. Method Four high-crash interstate highway corridors, each approximately 25 miles in length, were selected. Two of these corridors received TACT media messages and increased enforcement over an 18-month period while two comparison corridors did not receive any increased media or enforcement. Results A total of 4,737 contacts were made with drivers during the two enforcement waves, and 72% of these contacts led to a citation. Drivers at the intervention sites who said they saw or heard any of the TACT messages increased from 17.7% in the pre period to a high of 67.3% in the post periods. Drivers at the intervention sites also reported increased exposure to the core message of leaving more space when passing trucks (14% pre to 40% post period). The percentage of drivers who said they leave more room when passing trucks than when passing cars rose from 16% in the pre period to 24% in the post period at the intervention sites, while comparison sites showed no change. Over 150 hours of video recorded by law enforcement officers in unmarked vehicles were utilized to examine violation rates and severity of violations before and after the intervention campaigns. Statistical analyses showed that violation rates were reduced significantly at the intervention sites (between 23% and 46%), while remaining constant at the comparison sites. Analyses of the video data also showed that the seriousness of the residual violations at the intervention sites decreased. Conclusions Overall, the evaluation results provide a consistent picture of the effectiveness of the TACT pilot project. Success was demonstrated at every step - messages were received and understood, knowledge was changed in the intended direction, self reported driving behavior around large trucks improved, and observed driving behaviors confirmed the self reports. Impact on Industry After this initial success in Washington State, the TACT model will continue to be implemented and evaluated by FMCSA in an attempt to validate the program. Based on the results of this study and the consistent positive results found for other sTEP projects, it is likely that TACT will show continued success in a variety of settings and will help reduce the number and severity of crashes involving CMVs. Future research should attempt to use many of the methods described here to further validate the methods for not only evaluations of TACT programs, but also for any other highway safety programs that require measurements of the program's effectiveness.

Problem: Given the public safety risk posed by violation and crash repeaters and the substantial costs for state driver improvement programs, it is important that their effectiveness be scientifically demonstrated and that intervention programs are based on sound research findings. Method: Crash and traffic violation standardized effect sizes (d) representing 106 individual interventions were coded from 35 methodologically sound studies and analyzed using meta-analysis. Results: Driver improvement intervention in general was associated with small but significant reductions in both crashes (dw = 0.03) and violations (dw = 0.06). Significant effects were found on both measures for warning letters, group meetings, individual hearings, and license suspense/revocation. Of the driver improvement interventions studied, license suspension/revocation was by far the most effective treatment for both crashes and violations (dw = 0.11 and 0.19). Since one of the objectives of license suspension/revocation is to eliminate driving for the period of suspension, it is possible that much or all of the effect is due to reduced exposure and/or more careful driving during the suspension interval. Results were mixed for other types of interventions, although distributing educational or informational material was not associated with any reductions. Interventions associated with violation reduction tended to also be associated with crash reduction, although the relationship was not very strong (r = .30). Discussion: Although interpretation of the effect size estimates was complicated by almost ubiquitous heterogeneity, the results do suggest an overall positive impact of driver improvement interventions in general. Impact on Industry: The results support the continued use of driver improvement interventions, chiefly warning letters, group meetings, individual hearings, and especially license suspension/revocation. The results also suggest that court-triggered traffic violator programs are less effective than interventions triggered by drivers license agencies.

One of the primary missions of the California Department of Motor Vehicles is to protect the public from drivers who represent unacceptably high accident risks. Optimum fulfillment of this objective requires the development and implementation of strategies for identifying high-risk drivers. One such system in California is the department's negligent operator point system. This system assigns points to moving violations and accidents and authorizes the department to take driver control actions against drivers who meet the prima facie definition of a negligent operator. The present study explored the viability of predicting accidents from equations constructed to predict convictions for the general driving population. Equations or models that better identify drivers at increased risk of future accident involvement would increase the number of accidents prevented through post license control actions. Although the results did not support prior findings that equations keyed to citations do as well as or better than equations keyed to accidents in predicting subsequent accident involvement, a canonical correlation approach considering subsequent accident and citation rates simultaneously produced a 14.9% improvement in the classification accuracy or "hit rate" for identifying accident-involved drivers.

Problem: It is estimated that at least 75% of suspended or revoked drivers continue to drive illegally. In states like California, there are also a substantial and growing number of people who drive without ever having been licensed. Some states, such as Ohio and California, have enacted vehicle impoundment and forfeiture programs as sanctions to reduce these offenses. Published evaluations indicate that vehicle impoundment laws reduce recidivism and crash rates. However, vehicle forfeiture programs have been less successful, mostly because of low levels of enforcement. Method: Police officers and district attorneys from 17 jurisdictions were interviewed by phone or in person to determine current enforcement levels and impediments to more aggressive application of statutory authority. Results and discussion: The survey found that most California jurisdictions are enforcing vehicle impoundments for first-time offenders. However, very few jurisdictions were enforcing the vehicle forfeiture law for repeat offenders. Among the reasons for not enforcing the vehicle forfeiture law was a perception that it was too time-consuming and/or not a priority among prosecutors. However, a number of authorities indicated that the simple vehicle impoundment procedure is often functionally equivalent to forfeiture because many drivers fail to retrieve the vehicle at the end of the impoundment period. Impact on industry: Vehicle impoundment programs are effective mechanisms in deterring illicit driving, and states should be encouraged to initiate vehicle impoundment laws. States could achieve even greater safety benefits if vehicle forfeiture sanctions were extensively used for repeat offenders. However, based on California's experience, the incremental benefits of vehicle forfeiture (over vehicle impoundment) may not be very great.

We have developed the first in a planned series of neural prosthetic interfaces that allow multichannel systems to be assembled from single-channel micromodules called BIONs (BIOnic Neurons). Multiple BION implants can be injected directly into the sites requiring stimulating or sensing channels, where they receive power and digital commands by inductive coupling to an externally generated radio-frequency magnetic field. This article describes some of the novel technology required to achieve the required microminiaturization, hermeticity, power efficiency and clinical performance. The BION1 implants are now being used to electrically exercise paralyzed and weak muscles to prevent or reverse disuse atrophy. This modular, wireless approach to interfacing with the peripheral nervous system should facilitate the development of progressively more complex systems required to address a growing range of clinical applications, leading ultimately to synthesizing complete voluntary functions such as reach and grasp.

There have been a number of studies conducted during the past three decades which show that most suspended/revoked (S/R) drivers violate their license action and continue to drive during their period of disqualification. Traffic safety researchers also suspect that S/R drivers are overinvolved in traffic crashes, but this is difficult to demonstrate because of the lack of good data on their prevalence among all road users. This paper applies the quasi-induced exposure method to fatal crash data obtained from the National Highway Traffic Safety Administration's Fatal Accident Reporting System, to generate exposure and crash rate estimates for S/R drivers in California. The results show exposure rates of 8.8% and 3.3% for suspended/revoked and unlicensed drivers, respectively, and that, compared to validly licensed drivers, the former are overinvolved in fatal crashes by a factor of 3.7:1, and the latter 4.9:1. These findings provide support for efforts to better control S/R and unlicensed drivers. The paper also discusses serious limitations to using quasi-induced exposure to estimate the numbers of such drivers on California roads, and concludes that it is not suited to this task.

We describe the design, fabrication, and output capabilities of a microminiature electrical stimulator that can be injected in or near nerves and muscles. Each single-channel microstimulator consists of a cylindrical glass capsule with hermetically sealed electrodes in either end (2-mm diameter x 13-mm overall length). Power and digital control data can be transmitted to multiple implants (256 unique addresses) via a 2-MHz RF field created by an external AM oscillator and inductive coil. In vitro testing demonstrated accurate control of output pulsewidth (3-258 microseconds in 1-microseconds steps) and current (0-30 mA in two linear ranges of 16 steps each, up to 8.5 V available compliance voltage). Microstimulators were used successfully for chronic stimulation in hindlimb muscles of cats. Design and fabrication issues affecting yield and reliability of the packaging and electronics are discussed.

This article has been retracted: please see Elsevier Policy on Article Withdrawal ( http://www.elsevier.com/locate/withdrawalpolicy ). This reprinted article has been retracted at the request of the Publisher. The online version of this reprint has been withdrawn as it was a redundant duplicate of the original article. The original can be found via http://dx.doi.org/10.1016/0022-4375(92)90024-4 . The Publisher apologizes for any inconvenience this may cause.

This article has been retracted: please see Elsevier Policy on Article Withdrawal ( http://www.elsevier.com/locate/withdrawalpolicy ). This reprinted article has been retracted at the request of the Publisher. The online version of this reprint has been withdrawn as it was a redundant duplicate of the original article. The Publisher apologizes for any inconvenience this may cause.

We are developing a self-contained cardiac pacemaker with a small, cylindrical shape (~3 × 20 mm) that permits it to be implanted percutaneously into a fetus to treat complete heart block and consequent hydrops fetalis, which is otherwise fatal. The device uses off-the-shelf components including a rechargeable lithium cell and a highly efficient relaxation oscillator encapsulated in epoxy and glass. A corkscrew electrode made from activated iridium can be screwed into the myocardium, followed by release of the pacemaker and a short, flexible lead entirely within the chest of the fetus to avoid dislodgement from fetal movement. The feasibility of implanting the device percutaneously under ultrasonic imaging guidance was demonstrated in acute adult rabbit experiments.

A comparative study of 5 different designs of nerve cuff electrodes was undertaken to determine their relative merits for stimulating and recording whole-nerve activity over extended periods of chronic implantation on large and small peripheral nerves in 8 cats. Four of the designs represent novel fabrication strategies, including 2 based on flexible, thin-film substrates and 2 based on dip-coating silicone elastomer on a cylindrical mandrel. Various advantages and shortcomings of these materials and designs are discussed in the context of the biophysical factors that influence these electrophysiological interfaces, particularly the problem of recording microvolt-level neurograms in the presence of millivolt-level electromyograms from adjacent muscles in freely behaving subjects. The most effective design was one in which a thin sheath of silicone rubber was wrapped around and intra-operatively sealed to a longitudinally slit, tripolar cuff made by dip-coating silicone over stranded stainless steel leads that were prepositioned on a mandrel using polyvinyl alcohol as a temporary adhesive. When properly installed, these electrodes had stable impedances, recruitment thresholds and relatively interference-free recording properties for the duration of this study (up to 9 weeks).

The performance of metal microelectrodes for stimulating and recording neuronal action potentials depends on precise control of their geometrical, electrical and mechanical properties. We describe a combination of materials whose properties approach fundamental physical limitations on achievable performance and reproducible fabrication techniques that provide probes with very small dimensions. Pure iridium wire is electrolytically sharpened, vapor-coated with Parylene-C insulation and the tip exposed using an automatically steerable UV laser. Electrochemical activation of the iridium increases the capacitance of the metal-electrolyte interface so that the overall impedance in the relevant frequency band (100-10,000 Hz) is dominated by the access resistance of the surrounding tissues.

We provide a general method for producing a variety of small, complex electrode arrays based on injection molds produced using computer-aided drafting and machining (CAD-CAM) procedures and a novel method for connecting to the very fine electrical leads associated with the individual contacts of such arrays. Cat-sized cochlear electrode arrays with up to eight contacts were built according to these methods and their electrical contacts were characterized in vitro by impedance spectroscopy and in vivo by monitoring impedance for over 1 year of intermittent stimulation in chronically instrumented animals.

Comment on: "Comment on Mannering's "Male/female driver characteristics and accident risk: some new evidence". Peck RC. Accid Anal Prev. 1994; 26(1):130-133." Language: en

Data availability has forced researchers to examine separately the role of alcohol among drivers who crashed and drivers who did not crash. Such a separation fails to account fully for the transition from impaired driving to an alcohol-related crash.In this study, we analyzed recent data to investigate how traffic-related environments, conditions, and drivers' demographics shape the likelihood of a driver being either involved in a crash (alcohol impaired or not) or not involved in a crash (alcohol impaired or not). Our data, from a recent case-control study, included a comprehensive sampling of the drivers in nonfatal crashes and a matched set of comparison drivers in two U.S. locations. Multinomial logistic regression was applied to investigate the likelihood that a driver would crash or would not crash, either with a blood alcohol concentration (BAC)=.00 or with a BAC≥.05.To our knowledge, this study is the first to examine how different driver characteristics and environmental factors simultaneously contribute to alcohol use by crash-involved and non-crash-involved drivers. This effort calls attention to the need for research on the simultaneous roles played by all the factors that may contribute to motor vehicle crashes.

Studies have consistently shown that while young drivers pose the greatest accident risk, there is evidence of an increase in the accident rate (per driver) among older drivers at about 70 years of age. If the rates are further adjusted for mileage, the increase begins at about age 50 and becomes very steep at 70 and above. Evidence suggests that the increase in the accident rate among older drivers is attributable to age-related decrements in driving skill combined with an increased vulnerability to injury and death following trauma. This paper presents a number of analyses examining the possibility of an interactive relationship between age and prior driving record as a method for identifying high-risk drivers. The results indicate that older drivers exhibit a steeper increase in future accident risk at successive prior incident levels, relative to drivers in general. The report concludes that a record of traffic convictions presents a higher risk of accidents for older drivers than for younger drivers. Several hypotheses are offered to explain these findings. The report recommends revising the Department's negligent driver and accident reexamination process to initiate actions against older drivers based on fewer incidents.

Since the 1970s, nighttime fatal crashes have been used as a surrogate measure for alcohol-related fatalities for crashes for which more direct measures were absent. The validity of this approach was confirmed in 1985 but has not been re-evaluated since. Although this measure has also been applied to identify alcohol involvement in nonfatal crashes, its validity when applied to nonfatal cases has never been determined. The objective of this study was to evaluate the appropriateness of using nighttime crashes as surrogate measures for alcohol impairment when applied to fatal and nonfatal injury and property damage only (PDO) crashes. To do so, we used data from a crash-control design study collected at the roadside in two U.S. states between 1997 and 1999, as well as from the 1997-1999 and 2004-2006 Fatality Analysis Reporting System. The outcome of this study confirms the validity of using nighttime crashes as a surrogate measure for alcohol-related fatalities and supports the use of after-midnight crashes for measuring alcohol involvement in nonfatal and PDO crashes when the number of late-night crashes permits.

Several groups are developing different versions of a new class of leadless, permanently implanted electronic devices with a size and form factor that allows them to be injected into muscles (BIONs™). Their circuitry is protected from body fluids by thin-walled hermetic capsules made from rigid and brittle materials (glass or ceramic) that include feedthroughs to their electrodes. These packages experience repetitive stresses from the very contractions that they excite. We here provide a worst-case analysis of such stresses and methods for testing and validation of devices intended for such usage, along with the failure analysis and remediation strategy for a design that experienced unanticipated failures in vivo.

BIONs/spl trade/ are chronically implanted, individually addressable, single channel electrical stimulators that are now in clinical trials. They receive power and command signals from an externally worn RF transmission coil. The electronic circuitry is packaged in a glass capsule that can be injected through a hypodermic needle to provide distributed multichannel FES systems. The small size (2 mm OD /spl times/ 16 mm long), external electrodes and long design life (>10 years) pose a challenge for hermetic sealing and testing. We here describe several novel packaging techniques that have been integrated into a single workstation to enable efficient and reliable production of BION implants.

Virtually all bodily functions are controlled by electrical signals in nerves and muscles. Electrical stimulation can restore missing signals but this has been difficult to achieve practically because of limitations in the bioelectric interfaces. Wireless, injectable microdevices are versatile, robust and relatively inexpensive to implant in a variety of sites and applications. Several variants are now in clinical use or under development to perform stimulation and/or sensing functions and to operate autonomously or with continuous coordination and feedback control.

Comment on: Final results from a meta-analysis of remedial interventions with drink/drive offenders. Wells-Parker E, Bangert-Drowns R, McMillen R, Williams M. Addiction 1995; 90(7):907-926. Language: en

Graduated Driver Licensing (GDL) inserts between the leaner permit and full licensure an intermediate or ''provisional'' license that allows novices to drive unsupervised but subject to provisions intended to reduce the risks that accompany entry into highway traffic. Introduction of GDL has been followed by lowered accident rates, resulting from both limiting exposure of novices to unsafe situations and by helping them to deal with them more safely. Sources of safer driving include extended learning, early intervention, contingent advancement, and multistage instruction. To extend the learning process, most GDL systems lengthen the duration of the learner phase and require a specified level of adult-supervised driving. Results indicate that extended learning can reduce accidents substantially if well structured and highly controlled. Early intervention with novice traffic violators have shown both a general deterrent effect upon novice violators facing suspension and a specific effect upon those who have experienced it. Making advancement to full licensure contingent upon a violation-free record when driving on the provisional license has also evidenced a reduction in accidents and violations during that phase of licensure. Multistage instruction attempts development of advanced skills only after novices have had a chance to master more basic skills. Although this element of GDL has yet to be evaluated, research indicates crash reduction is possible in situations where it does not increase exposure to risk. While the various elements of GDL have demonstrated potential benefit in enhancing the safety of novice drivers, considerable improvement in the nature and enforcement of GDL requirements is needed to realize that potential. D 2002 National Safety Council and Elsevier Science Ltd. All rights reserved.

The goal of this project is to develop complete clinical systems for the application of functional electrical stimulation to alleviate disabilities and morbidity associated with musculoskeletal paralysis and atrophy. Over the past 8 years, the authors have designed, built and successfully tested in animals the first device in a new class of implantable electronic interfaces with nerve and muscle. BIONs are hermetically encapsulated, leadless electrical devices that are small enough to be injected percutaneously into muscles (2 mm diameter by 15 mm long). They receive their power and digital addressing and command signals from an external transmitter coil that can be worn by or placed under the patient. The authors have designed and built a family of accessory items required for clinical trials, including sterile testing and insertion tools and a bedside control unit so that clinicians can program various patterns of therapeutic stimulation to build strength and bulk in hypotrophic muscles, e.g. following stroke, spinal cord injury, major trauma and orthopedic reconstructions. Other potential applications include urinary incontinence, prevention of deep vein thrombosis and alleviation of chronic pain. Functional recovery of limb movement requires feedback signals about ongoing movement, for which the authors are developing second-generation BIONs that provide outgoing telemetry of such data.

MicroStimulators are electronic devices that can be injected into muscles to exercise and strengthen them, following, for example, a stroke or arthroplastic surgery. The authors have designed a bedside controller and user-interactive software that enable a clinician to test devices, identify multiple implantation sites and set up an exercise program that the patient can then self-administer. The system consists of a Motorola 68HC11 microcontroller, field-programmable gate array, and Windows/sup TM/ based software. The bedside controller maintains a record of treatment sessions administered while it is used in its stand-alone configuration.

Micromodular electrical stimulators called BIONs/sup TM/ (BIOnic Neurons) are injected into paralyzed muscles to treat disuse atrophy. The small, narrow shape required novel solutions to address requirements for wireless power and data transmission, electromechanical assembly and biocompatible hermetic packaging. Analysis of these problems provides some insights into the limits of the constituent microtechnologies.

The California Department of Motor Vehicles currently uses first-class mail to notify drivers of a suspension or revocation of their driving privilege. The served drivers are instructed to sign and return the order and any driver's license to the department, thereby establishing proof of the driver's knowledge of the order. The establishment of proof is considered essential in the prosecution of drivers cited for operating a motor vehicle while under a suspension or revocation (California Vehicle Code Section 14601). However, past research indicates that a majority of drivers fail to comply with the order. In an attempt to increase proof rates, the present study developed and evaluated a number of mailing strategies for various categories of suspensions and revocations. Among the mailing factors evaluated were (1) use of certified mail, (2) use of a follow-up contact, (3) use of a postage paid return envelope and (4) masking the Department of Motor Vehicles return address of the certified mail action notice. The results indicate that there are significant differences between the type of mail contact employed as well as between the different categories of suspension or revocation reason. The most effective strategies (certified mail, return receipt requested) resulted in proof rates of approximately 60-70% compared to approximately 25% for the current first-class mailing procedure. An analysis of subsequent driving records indicated that certified mail also increased the percentage of convictions which were prosecuted as 14601 violations, while decreasing the total number of entries (convictions and accidents) accumulated during suspension or revocation.

The primary objective of this study was to assess the extent to which drunk-driving (DUI) recidivism and DUI treatment program compliance could be predicted from psychometric, biographical, drinking history and prior-driving-record variables. These analyses were performed on data from 7,316 DUI offenders initially collected in Sacramento County, California, from September 1977 through January 1981. For most analyses, the recidivism measure was a composite of major convictions (DUI, reckless, hit-and-run), nighttime (6 PM-6 AM) and alcohol-related accidents during the 4-year interval following treatment assignment. The prediction of recidivism was highly significant for both the construct sample and the 25% cross-validation sample. The predictive accuracy was low, however, as evidenced by multiple Rs of.30. The predicted rates of recidivism generated for each individual by the regression equation were cross tabulated by other criteria of interest, including total accidents and total injury and fatal accidents. Offenders at high risk of recidivating had substantially higher rates of accidents. The results indicate that reasonably accurate prediction of recidivism is only possible for discriminating between offenders at the extremes of the recidivism expectancy distribution. The above approach was also used to isolate factors predictive of program compliance (successfully completing treatment). In all cases, the prediction of compliance was highly statistically significant. In general, compliance was much more predictable than was subsequent DUI recidivism. Those offenders having a high probability of being noncompliant were much more likely to recidivate and have accidents than were those with favorable compliance expectancies.

During the 4-year period following a repeat driving under the influence (DUI) conviction, participants in 12-month treatment programs had worse overall traffic safety records than did recipients of license suspensions. The results from a series of analyses using repeated measures analysis of covariance showed that, in comparison with license-suspension recipients: (i) participants had significantly higher rates (70%) of nonalcohol-related accidents and convictions, (ii) participants had a significantly lower rate (9%) of alcohol-related convictions, but no difference was found on alcohol-related accidents, and (iii) participants had a significantly higher rate (30%) of total accidents (p less than .05). These results suggest that the use of license-suspension waiver as an incentive to participate in a drinking driver program had a negative impact on traffic safety. The predicted reductions in alcohol-related accidents among program participants did not occur, and reductions in nonalcohol-related accidents, which could have been achieved with license suspensions, were sacrificed. It was recommended that some other alternative besides license-suspension waivers be used as an inducement for repeat DUI offenders to participate in treatment.

The primary objectives of this study were to examine characteristics of drivers involved in fatal accidents and to determine if those drivers could be distinguished from California's general driving population on the basis of prior driving record. A sample of drivers involved in 1970–1971 fatal accidents was analyzed and compared to a sample of drivers from the general driving population during the same time period. Drivers who had been drinking prior to the accident, who were considered at-fault for the accident, or whose accident occurred at night were found to have worse prior driving records than other fatal accident-involved drivers. The results also indicated that, as a whole, drivers involved in fatal accidents had worse violation and/or accident records, as well as different demographic and license characteristics than drivers in the general population. The classification functions derived to predict fatal accidents, however, did not differ greatly from regression equations that have been constructed to predict total accidents. It was therefore concluded that prediction systems keyed to total accidents will, to a large extent, also identify high-risk fatal accident drivers.

The objectives of the study were: (1) to determine the relative importance of territory, prior driving record and other variables in predicting future accident involvement: and (2) to determine whether a driver's area of residence is a fair and actuarially sound rating factor. Starting with two separate random samples totaling more than 90,000 drivers, various prediction models were developed using multiple regression techniques to predict subsequent three year accident involvement frequency, Although both territory and prior driving record proved to have some validity in predicting a driver's accident risk, the accuracy of the prediction was low, with multiple correlations ranging from 0.08 to 0.25. Prior driving record, particularly a driver's previous number of traffic convictions, was a much better predictor than was territory. Although absence of accident cost (insurance loss) information precludes precise validation of insurance rate setting practices, both territory and prior driving record appear justifiable as rate factors. However, the relatively small unique predictive contribution of territory suggests that territory may be less important than previously believed.