Headway Time and Crashes Among Novice Teens and Experienced Adult Drivers in a Simulated Lead Truck Braking Scenario

Driving simulators can be used to evaluate driving performance under controlled, safe conditions. Teen drivers are at particular risk for motor vehicle crashes and simulated driving can provide important information on performance. We developed a new simulator protocol, the Simulated Driving Assessment (SDA), with the goal of providing a new tool for driver assessment and a common outcome measure for evaluation of training programs. As an initial effort to examine the validity of the SDA to differentiate performance according to experience, this analysis compared driving behaviors and crashes between novice teens (n=20) and experienced adults (n=17) on a high fidelity simulator for one common crash scenario, a rear-end crash. We examined headway time and crashes during a lead truck with sudden braking event in our SDA. We found that 35% of the novice teens crashed and none of the experienced adults crashed in this lead truck braking event; 50% of the teens versus 25% of the adults had a headway time time \u3c 3 seconds at the time of truck braking. Among the 10 teens with \u3c 3 seconds headway time , 70% crashed. Among all participants with a headway time of 2-3 seconds, further investigation revealed descriptive differences in throttle position and brake pedal force when comparing teens who crashed, teens who did not crash and adults (none of whom crashed). Even with a relatively small sample, we found statistically significant differences in headway time for adults and teens, providing preliminary construct validation for our new SDA

Examining virtual driving test performance and its relationship to individuals with HIV-associated neurocognitive disorders

SIGNIFICANCE: Existing screening tools for HIV-associated neurocognitive disorders (HAND) are often clinically impractical for detecting milder forms of impairment. The formal diagnosis of HAND requires an assessment of both cognition and impairment in activities of daily living (ADL). To address the critical need for identifying patients who may have disability associated with HAND, we implemented a low-cost screening tool, the Virtual Driving Test (VDT) platform, in a vulnerable cohort of people with HIV (PWH). The VDT presents an opportunity to cost-effectively screen for milder forms of impairment while providing practical guidance for a cognitively demanding ADL. OBJECTIVES: We aimed to: (1) evaluate whether VDT performance variables were associated with a HAND diagnosis and if so; (2) systematically identify a manageable subset of variables for use in a future screening model for HAND. As a secondary objective, we examined the relative associations of identified variables with impairment within the individual domains used to diagnose HAND. METHODS: In a cross-sectional design, 62 PWH were recruited from an established HIV cohort and completed a comprehensive neuropsychological assessment (CNPA), followed by a self-directed VDT. Dichotomized diagnoses of HAND-specific impairment and impairment within each of the seven CNPA domains were ascertained. A systematic variable selection process was used to reduce the large amount of VDT data generated, to a smaller subset of VDT variables, estimated to be associated with HAND. In addition, we examined associations between the identified variables and impairment within each of the CNPA domains. RESULTS: More than half of the participants ( CONCLUSION: We identified a subset of VDT performance variables that are associated with HAND and assess relevant functional abilities among individuals with HAND. Additional research is required to develop and validate a predictive HAND screening model incorporating this subset

Acute urinary retention after cesarean delivery: a case-control study

INTRODUCTION: This study aimed to identify risk factors for postpartum urinary retention (PPUR) after cesarean delivery (CD). METHODS: A case-control study design was used. Cases of PPUR after CD were identified using billing codes for CD and urinary retention and confirmed by chart review. Matched controls were identified in a 2:1 ratio using an obstetrics database and billing data. Patient demographics, operative, and anesthetic data were collected. Fisher exact tests and Wilcoxon rank sum tests were used to determine differences in medical risk factors, postoperative analgesic use, and catheter management between cases and controls. A modified Poisson conditional multivariate regression with robust error variances was used to estimate the odds ratios (ORs) for significant predictors. RESULTS: Thirty-four confirmed cases of PPUR were matched with 68 controls. The mean ages of cases and controls were 31 and 32 years, respectively. Cases and controls differed in gestational age (P = 0.01), diagnosis of diabetes (P = 0.05), and use of postoperative intravenous and oral narcotics (P \u3c 0.01 and P = 0.03, respectively). In a multivariate model including these factors, increasing gestational age was associated with decreased risk of PPUR [OR, 0.07; 95% confidence interval (CI), 0.01-0.48; P \u3c 0.01], whereas use of postoperative intravenous narcotics (OR, 4.51; 95% CI, 1.09-18.67; P = 0.038) and oral narcotics (OR, 4.99; 95% CI, 1.10-22.65; P = 0.037) were associated with increased risk. CONCLUSIONS: After matching for obstetric factors, use of postoperative narcotic analgesia was associated with increased risk of PPUR. Other operative and anesthetic factors had no association. Multicenter prospective studies are needed to investigate this association

Comparison of Virtual Driving Test Performance and On-Road Examination for Licensure Performance: A Replication Study

For novice drivers, passing the on-road examination (ORE) for licensure marks the transition from supervised to unsupervised driving. However, the first months post-licensure pose the highest lifetime risk of crashing. In partnership with the Ohio Bureau of Motor Vehicles (OBMV), we have developed a virtual driving test (VDT) to enhance new driver skills testing. Through simulation, license applicants were exposed to common serious crash scenarios too dangerous for inclusion in the ORE. In a previous study of an initial sample of 2,143 driver applicants in Ohio, the acceptability, feasibility and construct validity for the VDT was demonstrated: VDT performance variables (simulated traffic collisions and failing to stop at red lights and stop signs) were associated with failing the ORE (all