Updated population-level estimates of child restraint practices among children aged 0-12 years in Australia, 10 years after introduction of age-appropriate restraint use legislation.

OBJECTIVE: Optimal child passenger protection requires use of a restraint designed for the age/size of the child (appropriate use) that is used in the way the manufacturer intended (correct use).This study aimed to determine child restraint practices approximately 10 years after introduction of legislation requiring correct use of age-appropriate restraints for all children aged up to 7 years. METHODS: A stratified cluster sample was constructed to collect observational data from children aged 0-12 years across the Greater Sydney region of New South Wales (NSW). Methods replicated those used in a similar 2008 study. Population weighted estimates for restraint practices were generated, and logistic regression used to examine associations between restraint type, and child age with correct use accounting for the complex sample. RESULTS: Almost all children were appropriately restrained (99.3%, 95% CI 98.4% to 100%). However, less than half were correctly restrained (no error=27.3%, 95% CI 10.8% to 43.8%, no serious error=43.8%, 95% CI 35.0% to 52.7%). For any error, the odds of error decreased by 39% per year of age (OR 0.61, 95% CI 0.46 to 0.81) and for serious error by 25% per year (OR 0.75, 95% CI 0.60 to 0.93). CONCLUSION: The findings demonstrate high levels of appropriate restraint use among children across metropolitan Sydney approximately 10 years after introduction of legislation requiring age-appropriate restraint use until age 7, however, errors in the way restraints remain common. IMPLICATIONS FOR PUBLIC HEALTH: Given the negative impact incorrect use has on crash protection, continuing high rates of incorrect use may reduce effectiveness of legislative change on injury reduction.

Differences in participant characteristics and observed child restraint use between population-based and restraint fitting service samples.

OBJECTIVE: To compare characteristics and restraint use between a population-based and fitting service sample of child restraint users. METHOD: Characteristics of the two samples were compared using chi-squared tests. Differences in errors in restraint use observed in the two samples were modeled using logistic regression. RESULTS: There were significant differences in child age (p < 0.001), and restraint types (p < 0.001) between the two samples, with more younger children in the fitting service sample. Controlling for differences in restraint type, the odds that adult participants were female were 61% less in the fitting service sample than in the population-based sample (OR 0.39, 95%CI 0.21-0.71). The odds that adult participants perceived a large risk associated with restraint misuse (OR 3.62, 95%CI 1.33-9.84), had a household income in the highest bracket (OR 3.89, 95%CI 1.20-12.62) and were living in areas of highest socioeconomic advantage (OR 2.72, 95%CI 1.22-6.06) were approximately three times higher in the fitting service sample. Overall, more participants had errors in restraint use in the population-based sample (p = 0.021). However, after controlling for restraint type, securing errors were three times more likely (OR 3.34, 95%CI 1.12-10.2), and serious installation errors were almost twice as likely (OR 1.91, 95% CI 1.09-3.39) in the fitting service sample. CONCLUSIONS: While less resource intensive, convenience and/or fitting service samples may be less representative than population-based samples. Given the need for efficiency, methods that combine randomized population-based invitations to participate in restraint fitting check day events across geographically representative areas may be useful for ongoing surveillance of child restraint use.

Risk of Motor Vehicle Collisions and Culpability among Older Drivers Using Cannabis: A Meta-Analysis.

Limited studies have investigated the effects of cannabis use on driving among older adults, who represent the fastest growing segment of drivers globally. We conducted a systematic review and meta-analysis to evaluate the effects of delta-9-tetrahydrocannabinol (THC) exposure on risks of (1) motor vehicle collisions (MVC) and (2) culpability for MVCs among adults 50 years and older. Three reviewers screened 7022 studies identified through MEDLINE, EMBASE, CENTRAL, and PsycINFO. Odds Ratios (OR) were calculated using the Mantel-Haenszel method in Review Manager 5.4.1. Heterogeneity was assessed using I2. The National Heart, Lung, and Blood Institute tool was used to assess the quality of each study. Seven cross-sectional studies were included. Three studies evaluated culpability while four evaluated MVC. The pooled risk of MVC was not significantly different between THC-positive and THC-negative older drivers (OR, 95% CI 1.15 [0.40, 3.31]; I2 = 72%). In culpability studies, THC exposure was not significantly associated with an increased risk of being culpable for MVC among adults over the age of 50 (OR, 95% CI 1.24 [0.95, 1.61]; I2 = 0%). Inspection of funnel plots did not indicate publication bias. Our review found that THC exposure was not associated with MVC involvement nor with culpability for MVCs.

Candrive-Development of a Risk Stratification Tool for Older Drivers.

BACKGROUND: Assessing an older adult's fitness-to-drive is an important part of clinical decision making. However, most existing risk prediction tools only have a dichotomous design, which does not account for subtle differences in risk status for patients with complex medical conditions or changes over time. Our objective was to develop an older driver risk stratification tool (RST) to screen for medical fitness-to-drive in older adults. METHODS: Participants were active drivers aged 70 and older from 7 sites across 4 Canadian provinces. They underwent in-person assessments every 4 months with an annual comprehensive assessment. Participant vehicles were instrumented to provide vehicle and passive Global Positioning System (GPS) data. The primary outcome measure was police-reported, expert-validated, at-fault collision adjusted per annual kilometers driven. Predictor variables included physical, cognitive, and health assessment measures. RESULTS: A total of 928 older drivers were recruited for this study beginning in 2009. The average age at enrollment was 76.2 (standard deviation [SD] = 4.8) with 62.1% male participants. The mean duration for participation was 4.9 (SD = 1.6) years. The derived Candrive RST included 4 predictors. Out of 4 483 person-years of driving, 74.8% fell within the lowest risk category. Only 2.9% of person-years were in the highest risk category where the relative risk for at-fault collisions was 5.26 (95% confidence interval = 2.81-9.84) compared to the lowest risk group. CONCLUSIONS: For older drivers whose medical conditions create uncertainty regarding their fitness-to-drive, the Candrive RST may assist primary health care providers when initiating a conversation about driving and to guide further evaluation.

The Association between Psychological Resilience and Driving Behavior among Older Drivers in Australia.

This study compared a sample of Australian drivers aged 77 years and older to participants from an older driver longitudinal cohort study (Ozcandrive) and examined the relationship between resilience and self-reported driving measures within these samples. Using a survey with a subset of questions from Ozcandrive, data were collected from 237 older drivers throughout Australia. The two samples were analyzed for differences in demographics, health, resilience, and self-reported driving behavior. A series of multiple regression models were fit for each driving outcome measure for both samples. The two samples had both similarities and differences, with the largest difference observed for resilience. Strong and consistent associations were found between resilience and driving comfort, abilities, and frequency for the Australian sample. Across samples, resilience remained a significant variable in seven of 10 regression models, more than any other independent variable.

A Systematic Review of the Risks of Motor Vehicle Crashes Associated with Psychiatric Disorders.

OBJECTIVE: Psychiatric disorders and their treatments have the potential to adversely impact driving skills. However, it is unclear to what extent this poses a public health risk by increasing the risk of motor vehicle crashes (MVCs). The aim of this systematic review was to synthesize and critically appraise evidence on the risk of MVC for drivers with psychiatric disorders. METHOD: We conducted a systematic review of the MVC risk associated with psychiatric disorders using seven databases in November 2019. Two reviewers examined each study and extracted data. The National Heart, Lung, and Blood Institute Quality Assessment tools were used to assess each study's quality of evidence. RESULTS: We identified 24 studies that met the inclusion criteria, including eight cohort, 10 case-control, and six cross-sectional designs. Quality assessment ratings were "Good" for four studies, "Fair" for 10, and "Poor" for 10. Self-report or questionnaires were used in place of objective measures of either MVC, psychiatric disorder, or both in 12 studies, and only seven adjusted for driving exposure. Fifteen studies reported an increased risk of MVC associated with psychiatric disorders, and nine did not. There was no category of disorder that was consistently associated with increased MVC risk. CONCLUSION: The available evidence is mixed, not of high quality, and does not support a blanket restriction on drivers with psychiatric disorder. An individualized approach, as recommended by international guidelines, should continue. Further research should include objective assessments of psychiatric disorders and MVC risk and adjust for driving exposure.

Examining the contribution of psychological resilience on self-reported and naturalistic driving behavior of older adults.

INTRODUCTION: This study examined the contribution of psychological resilience on self-reported driving comfort, abilities, and restrictions, and on naturalistic driving (ND) behavior of older adults at two time points, five years apart (N = 111; Male: 65.8%, Mean age = 86.1 years). METHOD: Participants from the Ozcandrive older driver cohort study completed a demographic questionnaire, functional assessments, psychosocial driving questionnaires, and a resilience scale. Participants' vehicles were equipped with a recording device to monitor driving behavior throughout the study. Over 1.7 million kilometers of ND data were analyzed. RESULTS: There was a significant increase in resilience over time, and both self-reported and ND measures revealed reduced driving across five years. Hierarchical regression analyses using age, sex, driving exposure, functional measures, and resilience showed that adding resilience into the models at the final step resulted in statistically significant increases in the amount of variance explained for driving comfort during the day and night, perceived driving abilities, number of trips, trip distance, and proportion of night trips. CONCLUSIONS: This research leveraged the longitudinal nature of the Ozcandrive study to provide the first insights into the role of resilience and ND. The observed patterns of reduced driving, captured by both subjective and objective measures, are suggestive of increased levels of self-regulation. As resilience is associated with adaptive coping skills, older adults with higher resilience may be able to more effectively engage in appropriate coping behaviors with regard to driving behavior, safety, and mobility. PRACTICAL APPLICATIONS: Effective methods of increasing resilience in the context of driving is worthy of future research as it will provide valuable information about how older drivers navigate the process of aging as it relates to driving and may assist stakeholders in developing suitable measures to support older driver safety.

Child restraint headrest and belt routing design features and their association with child passenger behavior and restraint misuse.

OBJECTIVES: Ergonomic design of child restraint systems (CRS) may facilitate optimal travel behavior and crash protection of child passengers during motor vehicle trips. However there have been few studies examining the relationship between CRS design and child passenger travel behavior. The aim of this study was to examine whether associations between CRS design features and child passenger behavior exist during real-world, everyday vehicle trips. METHODS: Video from a naturalistic driving study (NDS) was analyzed in this study. Families drove an instrumented study vehicle for approximately two weeks with at least one child aged between one and eight years traveling in their own forward-facing (FF) CRS or belt positioning booster (BPB). Video for one child passenger was randomly selected from each trip for analysis. Video was coded for five-second epochs at nine time points (5%, 17%, 25%, 30%, 50%, 53%, 75%, 89% and 95% of trip length). Two types of child passenger travel behaviors were identified by manual review of the video and audio recordings: (i) optimal/suboptimal head position and (ii) correct/incorrect use of the internal harness/shoulder belt. Video screenshots were used to characterize CRS design features. Random effects logistic regression models were used to examine the associations between specific CRS design features and the travel behaviors of interest, whilst accounting for clustering of data by child and trip. RESULTS: Suboptimal head position was associated with the absence of a height adjustable headrest and a narrow headrest wing width in FFCRS. Incorrect harness use in a FFCRS was associated with the absence of an adjustable headrest, in addition to headrest features such as wing width and depth. In BPBs, a reduction in suboptimal head position was associated with the absence of a sash belt guide, however no restraint design features were associated with incorrect shoulder belt use. CONCLUSIONS: Some CRS design features may influence undesirable child passenger travel behavior. These early findings support enhanced and user-centric CRS design as a likely important mechanism to improve child passenger safety.

Can Age or Height Define Appropriate Thresholds for Transition to Adult Seat Belts? An Analysis of Observed Seat Belt Fit in Children Aged 7-12 Years.

This study aimed to investigate associations between demographic, anthropometric and vehicle factors and the fit of adult seat belts in children aged 7-12 years in passenger vehicles. Seat belt fit was assessed by inspection of 7-12-year-old children in their own cars. Logistic regressions examined associations between anthropometric and vehicle factors on achieving good seat belt fit. There were 40 participants included in the analysis, with 16 (40%) having good overall belt fit. The odds of achieving good overall seat belt fit increased by 15% (OR 1.15, 95% CI 1.04-1.27) with every centimeter increase in height and increased by 5% with every one-month increase in age (OR 1.045, 95% CI 1.001-1.10). Controlling for vehicle factors, neither age or height was significantly associated with overall good belt fit, and the discriminatory power of models including these metrics to predict good belt fit was 73% (AUC 0.73, 95% CI 0.55-0.91) and 74% (AUC 0.74, 95% CI 0.58-0.91). The results suggest that taller and older children have a better chance of achieving a good seat belt fit. However, with variations in seat geometry between vehicles, no single simple metric clearly defines an appropriate transition to the adult seat belt.

Impact of vision disorders and vision impairment on motor vehicle crash risk and on-road driving performance: A systematic review.

Vision is important for safe driving, but there is limited understanding regarding the impact of vision disorders on driving ability and safety. This systematic review evaluated and summarized evidence on the impact of vision disorders and impairment on motor vehicle crash (MVC) risk and on-road driving performance across seven databases, was prospectively registered with PROSPERO (CRD42020180135), and study quality rated using a standard tool. Forty-eight studies met the inclusion criteria for MVC risk (N = 36), on-road performance (N = 9), and both MVC risk and on-road performance (N = 3). Of these studies, less than half were rated as 'good' quality. Due to the small number of studies and often conflicting findings, it was not possible to draw firm conclusions for most vision disorders. However, evidence from several 'good' and 'fair' quality studies suggested increased MVC risk with binocular visual field impairment. There was mixed evidence regarding the impact of cataract, glaucoma, age-related macular degeneration and homonymous field loss on MVC risk and no evidence of increased MVC risk with mild VA impairment. This review highlights the need for well-designed future studies to further explore the impact of vision disorders and impairment on driving outcomes to inform evidence-based policy and fitness to drive guidelines.

Comparison of older and middle-aged drivers' driving performance in a naturalistic setting.

There is a concern in the public domain about driving safety among older drivers due the increase in age-associated medical conditions. It is not known how these medical changes impact driving performance and choice of driving environment. This study aimed to compare older drivers' (≥74 years) driving performance in a naturalistic setting to middle-aged drivers (35-64 years) on their chosen driving environment, and number, type and severity of errors. The effect of sex and perceived driving ability was also examined. Drivers' performance was studied using the electronic Driving Observation Schedule [eDOS]), a naturalistic observation approach. Fifty-three older (mean age = 80.6 years, 72% male) and 60 middle-aged (mean age = 50.0 years, 50% male) healthy drivers were recruited. Both groups made few driving errors that were mostly low-risk. Driving performance of older adults differed from middle-aged drivers; they drove on simpler routes (fewer intersections and lane changes) and made fewer errors. Findings are likely indicative of older drivers' use of adaptive strategies to maintain safe driving.

Investigating feasibility and preliminary efficacy of a simulator-based driving intervention for people with acquired brain injury: A randomised controlled pilot study.

OBJECTIVE: To investigate the feasibility and preliminary efficacy of a driving simulator intervention on driving outcomes following acquired brain injury. DESIGN: Pilot randomised controlled trial. SETTING: Occupational therapy driver assessment and rehabilitation service. SUBJECTS: Individuals post-acquired brain injury aiming to return to driving. INTERVENTION: Eight sessions of simulated driver training over four weeks, in addition to usual care. Control: Usual care only. MAIN MEASURES: Feasibility outcomes: Participant recruitment and retention; data completeness; therapy attendance and fidelity; adverse events. Performance outcomes: on-road driving performance; Simulator Sickness Questionnaire; Brain Injury Driving Self-Awareness Measure and Driving Comfort Scale - Daytime, assessed at baseline and five weeks post-randomisation. RESULTS: Out of 523 individuals screened, 22 (4%) were recruited and randomised, with 20 completing their allocated group (n = 12 Simulator, n = 8 Usual Care). For those who completed training, session attendance was 100% with simulator sickness rated, on average, as mild. Six individuals (50%) in the Simulator group failed the on-road assessment, versus two (25%) in the Usual Care group (P = 0.373). On average, the Simulator group reported a positive change in confidence ratings (M = 5.77, SD = 13.96) compared to the Usual Care group, who reported a negative change (M = -6.97, SD = 8.47), P = 0.034. The Simulator group (M = 0.67, SD = 3.34) demonstrated no significant change in self-awareness relative to the Usual Care group (M = -0.83, SD = 1.83, P = 0.325). CONCLUSIONS: With adjustments to inclusion criteria and recruitment strategies, it may be feasible to deliver the intervention and conduct a larger trial. There is potential benefit of simulator training for improving driver confidence after acquired brain injury.

Personal and Clinical Factors Associated with Older Drivers' Self-Awareness of Driving Performance.

Most older adults perceive themselves as good drivers; however, their perception may not be accurate, and could negatively affect their driving safety. This study examined the accuracy of older drivers' self-awareness of driving ability in their everyday driving environment by determining the concordance between the perceived (assessed by the Perceived Driving Ability [PDA] questionnaire) and actual (assessed by electronic Driving Observation Schedule [eDOS]) driving performance. One hundred and eight older drivers (male: 67.6%; age: mean = 80.6 years, standard deviation [SD] = 4.9 years) who participated in the study were classified into three groups: underestimation (19%), accurate estimation (29%), and overestimation (53%). Using the demographic and clinical functioning information collected in the Candrive annual assessments, an ordinal regression showed that two factors were related to the accuracy of self-awareness: older drivers with better visuo-motor processing speed measured by the Trail Making Test (TMT)-A and fewer self-reported comorbid conditions tended to overestimate their driving ability, and vice versa.

User experiences and perspectives of a driving simulator intervention for individuals with acquired brain injury: A qualitative study.

Driving a motor vehicle is a common rehabilitation goal following acquired brain injury (ABI). There is increasing interest in the use of driving simulators for driver rehabilitation post-ABI; however, there is still limited research demonstrating efficacy and acceptability. This study sought to examine the user experience of a driving simulator intervention for ABI survivors. Semi-structured interviews were conducted with 14 individuals, including 12 ABI survivors (42% male; Mean age = 53.92 years, SD age = 17.63) who completed the intervention, and 2 occupational therapist driver assessors who facilitated the intervention. Thematic analysis was adopted to analyse interview data. Findings suggest that individual differences (e.g., anxiety, previous experience) influenced participant response to training. The intervention allowed participants to practise various driving skills, re-familiarize themselves with the task of driving, and prepare for return to on-road driving within a safe environment. The intervention was perceived to be useful for enhancing driver self-awareness, autonomy, confidence and patience. Fidelity and simulator sickness were considered limitations of the simulator technology. Subjective accounts of the appropriateness of intervention components are also documented. Overall, the simulator intervention was reported to be a positive experience for participants. Themes emerging from this study can inform future driving simulator interventions for ABI survivors.

The development of a simulator-based intervention to rehabilitate driving skills in people with acquired brain injury.

PURPOSE: With little to guide researchers and clinicians on how best to develop driving simulator interventions for ABI survivors, we aimed to describe the development process of a driving simulator intervention for ABI survivors in a rehabilitation setting. METHOD: Intervention mapping methodology was used as a framework for the development of our driving simulator intervention. A qualitative synthesis of theoretical and empirical literature and stakeholder meetings enabled identification of factors affecting return to driving, selection of justifiable intervention goals, and identification of appropriate theoretically-informed techniques to facilitate change. These were used as a basis for design of intervention components and materials. A plan for delivery, implementation and evaluation was then developed. RESULTS: Determinants of driving ability, including knowledge and skills, self-efficacy, self-awareness of driving skills, awareness of risk and compensatory strategies were identified. These were applied to a range of tactical and operational driving behaviours to identify targets for change. Theoretically-informed strategies included direct instruction, repetition, graded difficulty, feedback and tailoring. An eight-session protocol, with a corresponding clinical manual, was developed for brain-injured patients who were referred for occupational therapy driving assessment. Protocols for recruitment, inclusion/exclusion criteria and facilitator training were developed, as well as a plan for evaluating feasibility, acceptability and effectiveness. CONCLUSIONS: Intervention mapping was a useful approach to systematically develop an intervention tailored to the rehabilitation hospital context to complement existing driver rehabilitation. The feasibility and effectiveness of the simulator programme developed in this study will be evaluated in future studies.IMPLICATIONS FOR REHABILITATIONWe were able to gather important information and provide recommendations to tailor a new driving simulator intervention for individuals with acquired brain injury within a rehabilitation service.The processes and methods described provide researchers and clinicians with a systematic process for the selection of driving simulator intervention components and delivery.This investigation can be used to educate rehabilitation clinicians and technicians to improve driver training and delivery to acquired brain injury survivors.

Peritonsillar Abscess and Antibiotic Prescribing for Respiratory Infection in Primary Care: A Population-Based Cohort Study and Decision-Analytic Model.

PURPOSE: To quantify the risk of peritonsillar abscess (PTA) following consultation for respiratory tract infection (RTI) in primary care. METHOD: A cohort study was conducted in the UK Clinical Practice Research Datalink including 718 general practices with 65,681,293 patient years of follow-up and 11,007 patients with a first episode of PTA. From a decision tree, Bayes theorem was employed to estimate both the probability of PTA following an RTI consultation if antibiotics were prescribed or not, and the number of patients needed to be treated with antibiotics to prevent 1 PTA. RESULTS: There were 11,007 patients with PTA with age-standardized incidence of new episodes of PTA of 17.2 per 100,000 patient years for men and 16.1 for women; 6,996 (64%) consulted their practitioner in the 30 days preceding PTA diagnosis, including 4,243 (39%) consulting for RTI. The probability of PTA following an RTI consultation was greatest in men aged 15 to 24 years with 1 PTA in 565 (95% uncertainty interval 527 to 605) RTI consultations without antibiotics prescribed but 1 in 1,139 consultations (1,044 to 1,242) if antibiotics were prescribed. One PTA might be avoided for every 1,121 (975 to 1,310) additional antibiotic prescriptions for men aged 15 to 24 years and 926 (814 to 1,063) for men aged 25 to 34 years. The risk of PTA following RTI consultation was smaller and the number needed to treat higher at other ages and risks were lower in women than men. CONCLUSIONS: The risk of PTA may be lower if antibiotics are prescribed for RTI but even in young men nearly 1,000 antibiotic prescriptions may be required to prevent 1 PTA case. We caution that lack of randomization and data standardization may bias estimates.

Probability of sepsis after infection consultations in primary care in the United Kingdom in 2002-2017: Population-based cohort study and decision analytic model.

BACKGROUND: Efforts to reduce unnecessary antibiotic prescribing have coincided with increasing awareness of sepsis. We aimed to estimate the probability of sepsis following infection consultations in primary care when antibiotics were or were not prescribed. METHODS AND FINDINGS: We conducted a cohort study including all registered patients at 706 general practices in the United Kingdom Clinical Practice Research Datalink, with 66.2 million person-years of follow-up from 2002 to 2017. There were 35,244 first episodes of sepsis (17,886, 51%, female; median age 71 years, interquartile range 57-82 years). Consultations for respiratory tract infection (RTI), skin or urinary tract infection (UTI), and antibiotic prescriptions were exposures. A Bayesian decision tree was used to estimate the probability (95% uncertainty intervals [UIs]) of sepsis following an infection consultation. Age, gender, and frailty were evaluated as association modifiers. The probability of sepsis was lower if an antibiotic was prescribed, but the number of antibiotic prescriptions required to prevent one episode of sepsis (number needed to treat [NNT]) decreased with age. At 0-4 years old, the NNT was 29,773 (95% UI 18,458-71,091) in boys and 27,014 (16,739-65,709) in girls; over 85 years old, NNT was 262 (236-293) in men and 385 (352-421) in women. Frailty was associated with greater risk of sepsis and lower NNT. For severely frail patients aged 55-64 years, the NNT was 247 (156-459) in men and 343 (234-556) in women. At all ages, the probability of sepsis was greatest for UTI, followed by skin infection, followed by RTI. At 65-74 years, the NNT following RTI was 1,257 (1,112-1,434) in men and 2,278 (1,966-2,686) in women; the NNT following skin infection was 503 (398-646) in men and 784 (602-1,051) in women; following UTI, the NNT was 121 (102-145) in men and 284 (241-342) in women. NNT values were generally smaller for the period from 2014 to 2017, when sepsis was diagnosed more frequently. Lack of random allocation to antibiotic therapy might have biased estimates; patients may sometimes experience sepsis or receive antibiotic prescriptions without these being recorded in primary care; recording of sepsis has increased over the study period. CONCLUSIONS: These stratified estimates of risk help to identify groups in which antibiotic prescribing may be more safely reduced. Risks of sepsis and benefits of antibiotics are more substantial among older adults, persons with more advanced frailty, or following UTIs.

A Process Evaluation Protocol for Examining the Impact of Instructions for Correct Use of Child Car Seats Designed through a Consumer-Driven Process and Evaluated in a Field-Based Randomised Controlled Trial.

The incorrect use of child car seats is common, with significant negative effects on crash protection for child passengers. There is currently little evidence for effective, practical countermeasures for incorrect use. The provision of clear and comprehensible materials on correct use supplied with restraints at the point of sale could be highly cost-effective and achieve similar benefits to restraint-fitting services or hands-on training; however, routinely supplied instructions in their current form are frequently difficult to understand. We are conducting a randomised controlled trial of the consumer-driven redesign of instructional materials, consisting of an instruction sheet, swing tags and online training videos. This paper presents the protocol that will be used in an innovate process evaluation that will use the primary outcome of overall serious misuse assessed at six months, together with a survey and semi-structured interviews to determine fidelity, dose and outcomes for all intervention participants. The study will assess intervention delivery and external factors that may impact the effectiveness of the intervention, including experience, health literacy, confidence and attitudes. When it has been conducted, this process evaluation will provide enhanced understanding of the mechanisms through which the intervention works or not, aspects of the implementation process key to success of the intervention and insight into how external factors influence the success of the intervention.

Changes in older drivers' self-awareness of driving ability over one year.

Older drivers' self-awareness of driving ability can prompt self-regulatory behaviors and modifications of their everyday driving performance. To date, studies have yet to examine how older drivers' self-awareness of changes in driving ability over time or identify the characteristics of those who can accurately monitor such changes. 64 older drivers (Age: Mean = 80.0 years, SD = 5.4; male: 70 %) were recruited and categorized into four groups based on the correspondence of changes in their perceived and actual driving ability over one year: 40 % of the participants were accurate in their stable or better driving ability over time, 30 % did not detect their driving performance had worsened and over-estimated their driving ability, and the remainder either accurately detected their performance had worsened or under-estimated their driving performance. No demographic or clinical factors were associated with older drivers' self-awareness of changes in driving ability over time, except the mental processing and executive functioning measured using the Trail Making Tests Part B, showed a marginal effect. Implications for clinical importance are discussed.

Serious bacterial infections and antibiotic prescribing in primary care: cohort study using electronic health records in the UK.

OBJECTIVE: This study evaluated whether serious bacterial infections are more frequent at family practices with lower antibiotic prescribing rates. DESIGN: Cohort study. SETTING: 706 UK family practices in the Clinical Practice Research Datalink from 2002 to 2017. PARTICIPANTS: 10.1 million registered patients with 69.3 million patient-years' follow-up. EXPOSURES: All antibiotic prescriptions, subgroups of acute and repeat antibiotic prescriptions, and proportion of antibiotic prescriptions associated with specific-coded indications. MAIN OUTCOME MEASURES: First episodes of serious bacterial infections. Poisson models were fitted adjusting for age group, gender, comorbidity, deprivation, region and calendar year, with random intercepts representing family practice-specific estimates. RESULTS: The age-standardised antibiotic prescribing rate per 1000 patient-years increased from 2002 (male 423; female 621) to 2012 (male 530; female 842) before declining to 2017 (male 449; female 753). The median family practice had an antibiotic prescribing rate of 648 per 1000 patient-years with 95% range for different practices of 430-1038 antibiotic prescriptions per 1000 patient-years. Specific coded indications were recorded for 58% of antibiotic prescriptions at the median family practice, the 95% range at different family practices was from 10% to 75%. There were 139 759 first episodes of serious bacterial infection. After adjusting for covariates and the proportion of coded consultations, there was no evidence that serious bacterial infections were lower at family practices with higher total antibiotic prescribing. The adjusted rate ratio for 20% higher total antibiotic prescribing was 1.03, (95% CI 1.00 to 1.06, p=0.074). CONCLUSIONS: We did not find population-level evidence that family practices with lower total antibiotic prescribing might have more frequent occurrence of serious bacterial infections overall. Improving the recording of infection episodes has potential to inform better antimicrobial stewardship in primary care.