Older driver retraining: An updated systematic review of evidence of effectiveness

Problem and Objective

The number of older drivers who might benefit from driver retraining is growing. A previous review on the effectiveness of older driver retraining included intervention studies up to 2004. The objective was to perform an updated systematic review of the effectiveness of older driver retraining for improving driving-related skills and reducing crash rates.

Method

Articles published from 2004-2008 were grouped according to the intervention provided and outcome studied. Randomized clinical trials (RCTs) were appraised using the Physiotherapy Evidence Database (PEDro) Scale and scored for quality according to their internal validity. Each intervention's effectiveness was then rated and assigned a level of evidence by combining pre- and post- 2004 findings.

Results

Three RCTs and one matched-pairs cohort design met the inclusion criteria. There is strong evidence (Level 1a) that education combined with on-road training improves driving performance and moderate evidence (Level 1b) that it improves knowledge. There is moderate evidence (Level 1b) that physical retraining improves driving performance. There is moderate evidence (Level 1b) that an educational intervention curriculum alone is not effective in reducing crashes.

Summary

The updated evidence on the effectiveness of retraining aimed at older drivers is sufficiently encouraging to merit assertive health promotion actions regarding intervention and program planning.

Impact on Industry

These positive findings warrant a comprehensive plan that has both behavioral and monetary incentives encouraging older driver participation in programs aimed at driver safety.     

Focus on mission success: Process safety for the Atychiphobist

Modern process plants are complex engineering systems. While thorough reviews of system safeguards are performed, catastrophic events continue to occur, often unfolding in unforeseen ways. Success in process safety demands safe processes, and understanding rare, high consequence events is central to the traditional process safety approach. This philosophy is common to all high-hazard industries, offering the potential for sharing approaches, experience, and lessons learned. The problem, however, is that people (and organizations and entire industries) who fear failure (atychiphobia) sometimes obsess about failure so much that they miss opportunities to succeed.This paper examines selected risk management practices in the power generation and aerospace industries and how those practices have led to improved performance. Risk informed decision making (RIDM) has had widespread application in the nuclear and aerospace industries, and is undergoing enhancements to become a key framework for risk management. Additionally, rather than focusing on avoidance of loss, there are emerging approaches supporting achievement of success. This approach provides a more direct link of risk to business and operational objectives, but does challenge conventional risk approaches founded in a loss prevention-centric view. The paper reflects upon risk informed decision making and success modeling, and suggests how these methods may be applied in the field of process safety. Specific examples are drawn from the defense in depth approach from the nuclear power industry and mission success concepts developed for NASA.     

Effect of chelating agents and solubility of cadmium complexes on uptake from soil by Brassica juncea

Brassica juncea, or Indian mustard, was grown in soil artificially contaminated with either a soluble salt, CdCl(2), at 186mg Cdkg(-1), or alternately an insoluble, basic salt, CdCO(3), at 90mg Cdkg(-1). These experiments study the range of Cd uptake by Indian mustard from conditions of very high Cd concentration in a soluble form to the other extreme with an insoluble Cd salt. After plants were established, four different chelating agents were applied. Chelating agents increased plant uptake of Cd from the CdCl(2) soil but did not significantly increase plant uptake of Cd from the CdCO(3) contaminated soil. Addition of ethylenediaminetetraacetic acid (EDTA) increased the plant concentration of Cd by almost 10-fold in soils contaminated with CdCl(2), with a concentration of 1283mg Cdkg(-1) in the dried EDTA-treated plants over a concentration of 131mg Cdkg(-1) in plants without added chelate. However, EDTA increased the aqueous solubility of Cd by 36 times over the soil matrix without added chelator, and thereby, increased the possibility of leaching. Other chelators used in both experiments were ethylenebis(oxyethylenenitrilo)tetraacetic acid, trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid, and diethylenetriaminepentaacetic acid (DTPA) increasing Cd in plants to 1240, 962, and 437mg Cdkg(-1), respectively. The other chelating agents increased the solubility of Cd in the leachate but not to the extent of EDTA. Comparing all chelating agents studied, DTPA increased plant uptake in terms of Cd in dried plant concentration most relative to the solubility of complexed Cd in runoff water.     

Assimilation efficiencies of Cd and Zn in the common carp (Cyprinus carpio): effects of metal concentration, temperature and prey type

The impact of several factors on the assimilation efficiency (AE) of Cd and Zn from food in the common carp (Cyprinus carpio) was studied. Tested prey species were midge larvae (Chironomus riparius), zebra mussels (Dreissena polymorpha) and oligochaetes (Tubifex tubifex). The Cd load of the larvae did not affect the Cd AE in the carp. The Zn AE however, was negatively related to the Zn load of the prey. Food quantity and starvation of the carp did not significantly affect the Cd AE. For Zn, a significant decrease in AE was found when carp were fed ad libitum. Decreasing the temperature from 25 degrees C to 15 degrees C did not influence the Cd AE, while for Zn a significant decrease of the AE was measured. Carp assimilated Cd from both zebra mussels and oligochaetes with a significantly lower efficiency in comparison to the midge larvae, although Zn AEs was prey independent.     

Differential responses of the freshwater wetland species Juncus effusus L. and Caltha palustris L. to iron supply in sulfidic environments

Sulfur pollution can lead to serious problems in freshwater wetlands, including phosphorus eutrophication and sulfide toxicity. We tested the effects of anaerobic iron-rich groundwater discharge in fens, simulated by iron injection, on two characteristic species (Juncus effusus and Caltha palustris) in a sulfidic environment. Biomass production of C. palustris roots showed an optimum response to the combined addition of iron and sulfide, with highest values at intermediate concentrations of both substances. Iron deficiency apparently occurred at low iron concentrations, while at high iron concentrations, growth was decreased. For J. effusus, in contrast, no toxic effects were found of both iron and sulfide. This could be explained by larger radial oxygen loss (ROL) of J. effusus and could not be explained by differences in phosphorous concentrations. The results of our experiments confirm that iron-rich groundwater discharge has the potential to affect vegetation composition through toxicity modification in sulfidic environments.     

Effects of metals on life cycle parameters of the earthworm Eisenia fetida exposed to field-contaminated, metal-polluted soils

Two control and eight field-contaminated, metal-polluted soils were inoculated with Eisenia fetida (Savigny, 1826). Three, 7, 14, 21, 28 and 42 days after inoculation, earthworm survival, body weight, cocoon production and hatching rate were measured. Seventeen metals were analysed in E. fetida tissue, bulk soil and soil solution. Soil organic carbon content, texture, pH and cation exchange capacity were also measured. Cocoon production and hatching rate were more sensitive to adverse conditions than survival or weight change. Soil properties other than metal concentration impacted toxicity. The most toxic soils were organic-poor (1-10 g C kg(-1)), sandy soils (c. 74% sand), with intermediate metal concentrations (e.g. 7150-13,100 mg Pb kg(-1), 2970-53,400 mg Zn kg(-1)). Significant relationships between soil properties and the life cycle parameters were determined. The best coefficients of correlation were generally found for texture, pH, Ag, Cd, Mg, Pb, Tl, and Zn both singularly and in multivariate regressions. Studies that use metal-amended artificial soils are not useful to predict toxicity of field multi-contaminated soils.     

Levels and trends of HBCD and BDEs in the European and Asian environments, with some information for other BFRs

In this paper, we review recent data for brominated flame retardants (particularly BDEs, HBCD and TBBP-A) in samples from the European and Asian environments, including recent temporal trend studies. Research is active and we cite over 100 studies published during 2005-2007. Environmental compartments studied comprise the atmosphere, indoor and outdoor air, sewage sludges, soils and sediments and a variety of biological samples and food chains. Findings include that the lack of reference materials for use in analytical quality control and method validation identified earlier has been addressed, and certified concentrations are now available for a number of BDE congeners in six pre-existing and one new reference materials. BDE209 was certified in three samples of indoor dust. The analysis of BDE209 remains problematic, but suitable methods for its determination are available and need to be applied. The contamination of indoor environments with BFRs has been recognised as representing a significant uptake pathway, particularly via dust. Additional data for TBBP-A are needed from areas, where it is produced and used, primarily Asia, as the worst-case scenario. As a reactive flame retardant it is less likely to leach from finished products. Also, issues regarding the importance of e-waste recycling as a source of BFRs to the local populations and the local environment require urgent study, certainly in China and possibly elsewhere. Generally, trends show a levelling in concentrations of BDEs and increases in concentrations of HBCD wherever determined and BDE209 in Asia.     

Lipid metabolism of the Antarctic krill Euphausia superba and its ecological implications

 Various developmental stages (early larvae to adults) of Euphausia superba have been collected in different seasons in the Weddell Sea, the Lazarev Sea and off the Antarctic Peninsula to investigate the role of lipids and fatty acids in the life cycle of the Antarctic krill. The total-lipid data for E. superba exhibited seasonal variations, with low lipid levels in late winter/early spring and the highest levels in autumn. Seasonal changes were most pronounced in the immature and adult specimens, increasing from about 10% lipid of dry mass to more than 40%. The fatty-acid compositions of the younger stages were dominated by 20:5(n-3), 22:6(n-3) and 16:0. These are typical phospholipid fatty acids, which are major biomembrane constituents. The phospholipid composition was similar in the older stages. With increasing storage of triacylglycerols in the lipid-rich immature and adult stages, the fatty acids 14:0, 16:0 and 18:1(n-9) prevailed, comprising about 70% of total triacylglycerol fatty acids. The trophic-marker fatty acids 16:1(n-7) and 18:4(n-3), indicating phytoplankton ingestion, were less abundant. They reflected, however, the dependence of the larvae on phytoplankton as well as the seasonal changes in algal composition. The generally close linear relationships between fatty acids and lipid suggest that the fatty-acid compositions of the collected specimens were largely independent of the respective developmental stage, season and region. The linear fit indicates that triacylglycerol accumulation started at a level of about 5% of total lipid. Considering the various overwintering scenarios under discussion, the life cycle and reproductive strategies of krill are discussed in the context of the lipid metabolism and fatty-acid composition of E. superba. Lipid production is effective enough to accumulate large energy reserves for the dark season, but E. superba does not exhibit the sophisticated biosynthetic pathways known from other Antarctic euphausiids and copepods. Although important, lipid utilisation appears to be just one of several strategies of E. superba to thrive under the extreme Antarctic conditions, and this pronounced versatility may explain the success of this species in the Southern Ocean. Received: 16 June 2000 / Accepted: 18 December 2000     

Differences in herbivore preferences, phlorotannin production, and nutritional quality between juvenile and adult tissues from marine brown algae

 Juvenile and adult marine organisms differ in their morphology, chemistry, physiology, behavior, and ecology. Because juvenile algae are thinner, smaller, and have more delicate tissues than adults, they are often assumed to be more susceptible to grazers. We examined within-species food preferences of four common generalist herbivores for juvenile and adult tissues of eight common brown algae in two-choice laboratory food-preference experiments. Our results showed that juvenile algae did not tend to be a preferred food of herbivores. Juvenile tissues were significantly preferred over adult tissues in only four of the 32 combinations of algae and herbivores tested. In 12 experiments, adult tissues were preferred over juvenile tissues, and no choice occurred in the remaining 16 experiments. When sea urchins exhibited a preference, it was always for adult tissues. The other three herbivores, an isopod and two snails, were more variable in their choices, sometimes preferring juveniles, sometimes adults, and sometimes having no preference. We measured nitrogen and phlorotannin concentrations in adult and juvenile seaweeds to see whether these parameters were correlated with herbivore food preferences. Nitrogen levels were similar in juveniles and adults of three algal species and were higher in juveniles of two. Phlorotannin levels were higher in juveniles of four species and lower in juveniles of one. The other three species showed no differences in phlorotannin levels. Phlorotannin concentrations decreased with increasing juvenile size in three species and increased with increasing size in one species. Neither nitrogen nor phlorotannin concentrations explained overall herbivore food preferences for algae of different stages. Our results suggest that preferences of certain grazers for juvenile algae are not as strong as previously assumed and are dependent on herbivore species. Preferences between juveniles and adults are likely to be determined by a combination of morphological and chemical features of the tissues and the unique responses of herbivore species to those features. Received: 10 April 2000 / Accepted: 19 November 2000