Simulated Driving Assessment (SDA) for teen drivers: results from a validation study.

BACKGROUND: Driver error and inadequate skill are common critical reasons for novice teen driver crashes, yet few validated, standardised assessments of teen driving skills exist. The purpose of this study is to evaluate the construct and criterion validity of a newly developed Simulated Driving Assessment (SDA) for novice teen drivers. METHODS: The SDA's 35 min simulated drive incorporates 22 variations of the most common teen driver crash configurations. Driving performance was compared for 21 inexperienced teens (age 16-17 years, provisional license ≤90 days) and 17 experienced adults (age 25-50 years, license ≥5 years, drove ≥100 miles per week, no collisions or moving violations ≤3 years). SDA driving performance (Error Score) was based on driving safety measures derived from simulator and eye-tracking data. Negative driving outcomes included simulated collisions or run-off-the-road incidents. A professional driving evaluator/instructor (DEI Score) reviewed videos of SDA performance. RESULTS: The SDA demonstrated construct validity: (1) teens had a higher Error Score than adults (30 vs. 13, p=0.02); (2) For each additional error committed, the RR of a participant's propensity for a simulated negative driving outcome increased by 8% (95% CI 1.05 to 1.10, p<0.01). The SDA-demonstrated criterion validity: Error Score was correlated with DEI Score (r=-0.66, p<0.001). CONCLUSIONS: This study supports the concept of validated simulated driving tests like the SDA to assess novice driver skill in complex and hazardous driving scenarios. The SDA, as a standard protocol to evaluate teen driver performance, has the potential to facilitate screening and assessment of teen driving readiness and could be used to guide targeted skill training.

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 < 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 < 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.