Lynn Meuleners

Quality of life for adolescents: Assessing measurement properties using structural equation modelling

Assessments for quality of life (QOL) of the adolescent have received relatively little attention in the literature. Although there is no consensus on the definition of adolescent QOL and what aspects should be measured, it is generally accepted that QOL is a multidimensional construct. The objective of this study is to determine the measurement properties of the latent factors underlying adolescent QOL based on a second-order confirmatory factor analysis (CFA). A recursive structural equation model (SEM) is then proposed to determine the direction and magnitude of the interdependent effects among the latent factors. The questionnaire used was the Quality of Life Profile-Adolescent Version (QOLPAV). A sample of 363 adolescents was recruited from 20 secondary schools in Perth, Australia. The second-order CFA suggested that adolescent QOL may be measured by five underlying constructs namely social, environment, psychological, health, and opportunities for growth. The interdependent relations among these constructs identified the environment factor as primary, exerting both direct and indirect effects on the other four factors.

Psychoactive Medications and Crash Involvement Requiring Hospitalization for Older Drivers: A Population-Based Study

OBJECTIVES: To determine the association between psychoactive medications and crash risk in drivers aged 60 and older.

Assessing sleepiness and sleep disorders in Australian long-distance commercial vehicle drivers: self-report versus an "at home" monitoring device

STUDY OBJECTIVES As obstructive sleep apnea (OSA) is associated with a higher risk of motor vehicle crashes, there is increasing regulatory interest in the identification of commercial motor vehicle (CMV) drivers with this condition. This study aimed to determine the relationship between subjective versus objective assessment of OSA in CMV drivers. DESIGN Cross-sectional survey. SETTINGS Heavy vehicle truck stops located across the road network of 2 large Australian states. PARTICIPANTS A random sample of long distance commercial vehicle drivers (n = 517). INTERVENTIONS None. MEASUREMENTS AND RESULTS Drivers were interviewed regarding their driving experience, personal health, shift schedules, payments, and various questions on sleep and tiredness in order to describe their sleep health across a range of variables. In addition, home recordings using a flow monitor were used during one night of sleep. Only 4.4% of drivers reported a previous diagnosis of sleep apnea, while our at home diagnostic test found a further 41% of long-distance heavy vehicle drivers likely to have sleep apnea. The multivariable apnea prediction index, based on self-report measures, showed poor agreement with the home-monitor detected sleep apnea (AUC 0.58, 95%CI = 0.49-0.62), and only 12% of drivers reported daytime sleepiness (Epworth Sleepiness Scale score > 10). Thirty-six percent of drivers were overweight and a further 50% obese; 49% of drivers were cigarette smokers. CONCLUSIONS Sleep apnea remains a significant and unrecognized problem in CMV drivers, who we found to have multiple health risks. Objective testing for this sleep disorder needs to be considered, as symptom reports and self-identification appear insufficient to accurately identify those at risk.

Use of caffeinated substances and risk of crashes in long distance drivers of commercial vehicles: case-control study

Objective To determine whether there is an association between use of substances that contain caffeine and the risk of crash in long distance commercial vehicle drivers. Design Case-control study. Setting New South Wales (NSW) and Western Australia (WA), Australia. Participants 530 long distance drivers of commercial vehicles who were recently involved in a crash attended by police (cases) and 517 control drivers who had not had a crash while driving a commercial vehicle in the past 12 months. Main outcome measure The likelihood of a crash associated with the use of substances containing caffeine after adjustment for factors including age, health disorders, sleep patterns, and symptoms of sleep disorders as well as exposures such as kilometres driven, hours slept, breaks taken, and night driving schedules. Results Forty three percent of drivers reported consuming substances containing caffeine, such as tea, coffee, caffeine tablets, or energy drinks for the express purpose of staying awake. Only 3% reported using illegal stimulants such as amphetamine (“speed”); 3,4 methylenedioxymethamphetamine (ecstasy); and cocaine. After adjustment for potential confounders, drivers who consumed caffeinated substances for this purpose had a 63% reduced likelihood of crashing (odds ratio 0.37, 95% confidence interval 0.27 to 0.50) compared with drivers who did not take caffeinated substances. Conclusions Caffeinated substances are associated with a reduced risk of crashing for long distance commercial motor vehicle drivers. While comprehensive mandated strategies for fatigue management remain a priority, the use of caffeinated substances could be a useful adjunct strategy in the maintenance of alertness while driving.

The impact of first- and second-eye cataract surgery on injurious falls that require hospitalisation: a whole-population study

BACKGROUND cataract is a leading cause of reversible vision impairment and may increase falls in older adults. OBJECTIVE to assess the risk of an injury due to a fall among adults aged 60+, 2 years before first-eye cataract surgery, between first-eye surgery and second-eye surgery and 2 years after second-eye surgery. DESIGN a retrospective cohort study. SETTING Western Australian Hospital Morbidity Data System and the Western Australian Death Registry. SUBJECTS there were 28,396 individuals aged 60+ years who underwent bilateral cataract surgery in Western Australia between 2001 and 2008. METHODS Poisson regression analysis based on generalised estimating equations compared the frequency of falls 2 years before first-eye cataract surgery, between first- and second-eye surgery and 2 years after second-eye cataract surgery after accounting for potential confounders. RESULTS the risk of an injurious fall that required hospitalisation doubled (risk ratio: 2.14, 95% confidence interval: 1.82 to 2.51) between first- and second-eye cataract surgery compared with the 2 years before first-eye surgery. There was a 34% increase in the number of injurious falls that required hospitalisation in the 2 years after second-eye cataract surgery compared with the 2 years before first-eye surgery (risk ratio: 1.34, 95% confidence interval: 1.16-1.55). CONCLUSIONS there was an increased risk of injurious falls after first- and second-eye cataract surgery which has implications for the timely provision of second-eye surgery as well as appropriate refractive management between surgeries.

Prevalence and factors associated with road traffic crash among taxi drivers in Hanoi, Vietnam.

Injury due to road traffic crash is a major cause of ill health and premature deaths in developing countries. Taxis provide a main mode of public transport in Vietnam but there has been little research on the risk of crash for taxi drivers. This retrospective study collected information on taxi crashes for the period 2006-2009 by interviewing drivers from five taxi companies in Hanoi, Vietnam, using a structured questionnaire. Of the total 1214 participants recruited, 276 drivers reported at least one crash, giving an overall crash prevalence of 22.7%. Among the crashed group, 50 drivers (18.1%) were involved in two to four crashes. Logistic regression analysis further identified age of driver, type of driving licence, employment status, perceived sufficiency of income, seat-belt usage, and traffic infringement history to be significantly associated with the crash risk. Further prospective and qualitative studies are recommended to provide detailed crash characteristics as well as behaviour and perception of taxi drivers, so that an effective intervention can be developed to improve road safety and to prevent injury of these commercial drivers.

The Effectiveness of Cataract Surgery in Reducing Motor Vehicle Crashes: A Whole Population Study Using Linked Data

Purpose: To evaluate the effectiveness of first eye cataract surgery on drivers aged 60 years and over at a population level. Methods: A retrospective before and after comparison of all police reported crashes for patients who had undergone first eye cataract surgery using linked Western Australia data for the period 1997–2006. An economic analysis by the type of crash was performed on the cost savings from cataract surgery for this cohort. Results: Of the 27,827 patients who underwent cataract surgery in one eye only, 1715 patients were involved in 1762 police reported crash events, either 1 year before (n = 941 crashes) or 1 year after (n = 821 crashes) cataract surgery. Results from Poisson generalized estimating equations showed a significant reduction of 12.7% (P = 0.034) in all police reported crashes 1 year after cataract surgery. The corresponding cost savings amounted to

Effectiveness of the Black Spot Programs in Western Australia

4.3 million. Conclusion: The findings are important for policy development to further improve driving outcomes among older drivers.

Adolescent quality of life: a school-based cohort study in Western Australia.

This study evaluates the effectiveness of the Black Spot Programs in Western Australia. Reduction in crash rate at the treated locations and the economic benefits of these treatments were assessed. The results showed that the programs have been effective overall, reducing all reported crash rate by 15%. The estimated crash cost savings were 50.8 million Australian dollars, of which 89% could be attributed to the reduction in casualty crashes. This led to net savings to the community of 40.4 million Australian dollars (

Vision, quality of life and depressive symptoms after first eye cataract surgery.

35.1 million attributable to casualty crashes) after subtracting the capital costs of treating sites, maintenance and operating costs. The benefit cost ratio across all treatment sites was 4.9. Evaluation of the treatments has identified some effective treatment types and others without any significant change in either the rate or cost of crashes. The latter could be due to insufficient number of sites that received the treatment, the post-treatment period being relatively short, or the treatments genuinely had little impact on road safety. Findings of this study provide objective information for the development of effective strategies on road safety investment.