Sources of coding discrepancies in injury morbidity data: Implications for injury surveillance

Objective: To examine the sources of coding discrepancy for injury morbidity data and explore the implications of these sources for injury surveillance.-------- Method: An on-site medical record review and recoding study was conducted for 4373 injury-related hospital admissions across Australia. Codes from the original dataset were compared to the recoded data to explore the reliability of coded data aand sources of discrepancy.---------- Results: The most common reason for differences in coding overall was assigning the case to a different external cause category with 8.5% assigned to a different category. Differences in the specificity of codes assigned within a category accounted for 7.8% of coder difference. Differences in intent assignment accounted for 3.7% of the differences in code assignment.---------- Conclusions: In the situation where 8 percent of cases are misclassified by major category, the setting of injury targets on the basis of extent of burden is a somewhat blunt instrument Monitoring the effect of prevention programs aimed at reducing risk factors is not possible in datasets with this level of misclassification error in injury cause subcategories. Future research is needed to build the evidence base around the quality and utility of the ICD classification system and application of use of this for injury surveillance in the hospital environment.

Trauma and Injury Severity Score (TRISS) coefficients 2009 revision

Background: Currently used Trauma and Injury Severity Score (TRISS) coefficients, which measure probability of survival (Ps), were derived from the Major Trauma Outcome Study (MTOS) in 1995 and are now unlikely to be optimal. This study aims to estimate new TRISS coefficients using a contemporary database of injured patients presenting to emergency departments in the United States; and to compare these against the MTOS coefficients.---------- Methods: Data were obtained from the National Trauma Data Bank (NTDB) and the NTDB National Sample Project (NSP). TRISS coefficients were estimated using logistic regression. Separate coefficients were derived from complete case and multistage multiple imputation analyses for each NTDB and NSP dataset. Associated Ps over Injury Severity Score values were graphed and compared by age (adult ≥ 15 years; pediatric < 15 years) and injury mechanism (blunt; penetrating) groups. Area under the Receiver Operating Characteristic curves was used to assess coefficients’ predictive performance.---------- Results: Overall 1,072,033 NTDB and 1,278,563 weighted NSP injury events were included, compared with 23,177 used in the original MTOS analyses. Large differences were seen between results from complete case and imputed analyses. For blunt mechanism and adult penetrating mechanism injuries, there were similarities between coefficients estimated on imputed samples, and marked divergences between associated Ps estimated and those from the MTOS. However, negligible differences existed between area under the receiver operating characteristic curves estimates because the overwhelming majority of patients had minor trauma and survived. For pediatric penetrating mechanism injuries, variability in coefficients was large and Ps estimates unreliable.---------- Conclusions: Imputed NTDB coefficients are recommended as the TRISS coefficients 2009 revision for blunt mechanism and adult penetrating mechanism injuries. Coefficients for pediatric penetrating mechanism injuries could not be reliably estimated.

Thermal analysis and hot stage Raman spectroscopy of the basic copper arsenate mineral : euchroite

The thermal analysis of euchroite shows two mass loss steps in the temperature range 100 to 105°C and 185 to 205°C. These mass loss steps are attributed to dehydration and dehydroxylation of the mineral. Hot stage Raman spectroscopy (HSRS) has been used to study the thermal stability of the mineral euchroite, a mineral involved in a complex set of equilibria between the copper hydroxy arsenates: euchroite Cu2(AsO4)(OH).3H2O → olivenite Cu2(AsO4)(OH) → strashimirite Cu8(AsO4)4(OH)4.5H2O → arhbarite Cu2Mg(AsO4)(OH)3. Hot stage Raman spectroscopy inolves the collection of Raman spectra as a function of the temperature. HSRS shows that the mineral euchroite decomposes between 125 and 175 °C with the loss of water. At 125 °C, Raman bands are observed at 858 cm-1 assigned to the ν1 AsO43- symmetric stretching vibration and 801, 822 and 871 cm-1 assigned to the ν3 AsO43- (A1) antisymmetric stretching vibration. A distinct band shift is observed upon heating to 275 °C. At 275 °C the four Raman bands are resolved at 762, 810, 837 and 862 cm-1. Further heating results in the diminution of the intensity in the Raman spectra and this is attributed to sublimation of the arsenate mineral. Hot stage Raman spectroscopy is most useful technique for studying the thermal stability of minerals especially when only very small amounts of mineral are available.

Thermal decomposition of Bayer precipitates formed at varying temperatures

Bayer hydrotalcites prepared using the seawater neutralisation (SWN) process of Bayer liquors are characterised using X-ray diffraction and thermal analysis techniques. The Bayer hydrotalcites are synthesised at four different temperatures (0, 25, 55, 75 °C) to determine the effect on the thermal stability of the hydrotalcite structure, and to identify other precipitates that form at these temperatures. The interlayer distance increased with increasing synthesis temperature, up to 55 °C, and then decreased by 0.14 Å for Bayer hydrotalcites prepared at 75 °C. The three mineralogical phases identified in this investigation are; 1) Bayer hydrotalcite, 2), calcium carbonate species, and 3) hydromagnesite. The DTG curve can be separated into four decomposition steps; 1) the removal of adsorbed water and free interlayer water in hydrotalcite (30 – 230 °C), 2) the dehydroxylation of hydrotalcite and the decarbonation of hydrotalcite (250 – 400 °C), 3) the decarbonation of hydromagnesite (400 – 550 °C), and 4) the decarbonation of aragonite (550 – 650 °C).

Thermal analysis of synthetic reevesite and cobalt substituted reevesite (Ni,Co)6Fe2(OH)16(CO3)•4H2O

The mineral reevesite and the cobalt substituted reevesite have been synthesised. The d(003) spacings of the minerals ranged from 7.54 to 7.95 Å. The maximum d(003) value occurred at around Ni:Co 0.4:0.6. This maximum in interlayer distance is proposed to be due to a greater number of carbonate anions and water molecules intercalated into the structure. The stability of the reevesite and cobalt doped reevesite was determined by thermogravimetric analysis. The maximum temperature of the reevesite occurs for the unsubstituted reevesite and is around 220°C. The effect of cobalt substitution results in a decrease in thermal stability of the reevesites. Four thermal decomposition steps are observed and are attributed to dehydration, dehydroxylation and decarbonation, decomposition of the formed carbonate and oxygen loss at ~807 °C. A mechanism for the thermal decomposition of the reevesite and the cobalt substituted reevesite is proposed.

Synthesis and thermal stability of hydrotalcites containing manganese

The hydrotalcite based upon manganese known as charmarite Mn4Al2(OH)12CO3•3H2O has been synthesised with different Mn/Al ratios from 4:1 to 2:1. Impurities of manganese oxide, rhodochrosite and bayerite at low concentrations were also produced during the synthesis. The thermal stability of charmarite was investigated using thermogravimetry. The manganese hydrotalcite decomposed in stages with mass loss steps at 211, 305 and 793°C. The product of the thermal decomposition was amorphous material mixed with manganese oxide. A comparison is made with the thermal decomposition of the Mg/Al hydrotalcite. It is concluded that the synthetic charmarite is slightly less stable than hydrotalcite.

Knowledge, attitudes and beliefs towards injury prevention : a population based telephone survey

Public knowledge and beliefs about injury prevention are currently poorly understood. A total of 1030 residents in the State of Queensland, Australia responded to questions about injury prevention in or around the home, on the roads, in or on the water, at work, deliberate injury, and responsibility for preventing deliberate injury allowing comparison with published injury prevalence data. Overall the youngest members of society were identified as being the most vulnerable to deliberate injury with young adults accounting for 59% of responses aligning with published data. However, younger adults failed to indicate an awareness of their own vulnerability to deliberate injury in alcohol environments even though 61% of older respondents were aware of this trend. Older respondents were the least inclined to agree that they could make a difference to their own safety in or around the home but were more inclined to agree that they could make a difference to their own safety at work. The results are discussed with a view to using improved awareness of public beliefs about injury to identify barriers to the uptake of injury prevention strategies (e.g. low perceived injury risk) as well as areas where injury prevention strategies may receive public support.

Assessing the safety of a velocity sourced series elastic actuator using the head injury criterion

The Velocity Sourced Series Elastic Actuator has been proposed as a method for providing safe force or torque based actuation for robots without compromising the actuator performance. In this paper we assess the safety of Velocity Sourced Series Elastic Actuators by measuring the Head Injury Criterion scores for collisions with a model head. The study makes a comparative analysis against stiff, high impedance actuation using the same motor without the series elastic component, showing that the series elastic component brings about a massive reduction in the chance of head injury. The benefits of a collision detection and safe reaction system are shown to be limited to collisions at low speeds, providing greater interaction comfort but not necessarily contributing to safety from injury.

The properties of the international classification of the external cause of injury when used as an instrument for injury prevention research

Objective: To demonstrate properties of the International Classification of the External Cause of Injury (ICECI) as a tool for use in injury prevention research. Methods: The Childhood Injury Prevention Study (CHIPS) is a prospective longitudinal follow up study of a cohort of 871 children 5–12 years of age, with a nested case crossover component. The ICECI is the latest tool in the International Classification of Diseases (ICD) family and has been designed to improve the precision of coding injury events. The details of all injury events recorded in the study, as well as all measured injury related exposures, were coded using the ICECI. This paper reports a substudy on the utility and practicability of using the ICECI in the CHIPS to record exposures. Interrater reliability was quantified for a sample of injured participants using the Kappa statistic to measure concordance between codes independently coded by two research staff. Results: There were 767 diaries collected at baseline and event details from 563 injuries and exposure details from injury crossover periods. There were no event, location, or activity details which could not be coded using the ICECI. Kappa statistics for concordance between raters within each of the dimensions ranged from 0.31 to 0.93 for the injury events and 0.94 and 0.97 for activity and location in the control periods. Discussion: This study represents the first detailed account of the properties of the ICECI revealed by its use in a primary analytic epidemiological study of injury prevention. The results of this study provide considerable support for the ICECI and its further use.

Teachers’ understanding of school connectedness : implications for the development and implementation of school based injury prevention strategies

Aim: Worldwide, injury is the leading cause of death and disability for young people. Injuries among young people are commonly associated with risk taking behaviour, including violence and transport risks, which often occur in the context of alcohol use. The school environment has been identified as having a significant role in shaping adolescent behaviour. In particular, school connectedness, the degree to which adolescents feel that they belong and are accepted at school, has been shown to be an important protective factor. Strategies for increasing school connectedness may therefore be effective in reducing risk taking and associated injury. Prior to developing connectedness strategies, it is important to understand the perspectives of those in the school regarding the construct and how it is realised in the school context. The aim of this research was to understand teachers’ perspectives of school connectedness, the strategies they employ to connect with students, and their perceptions of school connectedness as a strategy for risk taking and injury prevention. Method: In depth interviews of approximately 45 minutes duration were conducted with 13 Health and PE teachers and support staff from 2 high schools in Southeast Queensland, Australia. Additionally, 6 focus group workshop discussions were held with 35 Education department employees (5-6 per group), including teachers from 15 Southeast Queensland high schools. Results: Participants were found to place strong importance on the development of connectedness among students, including those at risk for problem behaviour. Strategies used to promote connectedness included building trust, taking an interest in each student and being available to talk to, and finding something positive for students to succeed at. Teachers identified strategies as being related to decreased risk taking behavior. Teacher training on school connectedness was perceived as an important and useful inclusion in a school based injury prevention program. Conclusions: The established link between increased school connectedness and decreased problem behaviour has implications for school based strategies designed to decrease adolescent risk taking behaviour and associated injury. Targeting school connectedness as a point of intervention, in conjunction with individual attitude and behaviour change programs, may be an effective injury prevention strategy.

Do clients with acquired brain injury use the splints prescribed by occupational therapists? A descriptive study

Clients with acquired brain injury often demonstrate hypertonicity and decreased function in their upper limbs, requiring appropriate intervention. Splinting is one of the intervention methods that is widely used to address these issues. Literature shows that some clients are not using splints following fabrication. However, there is a paucity of research about the factors that influence clients to use or not use splints. This study aims to investigate these influential factors for clients with upper limb hypertonicity. Two survey tools including therapist and client questionnaires were developed and completed by both therapists and clients. Six therapists and 14 clients participated in this study and completed the relevant questionnaires. The results illustrate that most clients (13 out of 14) were continuing to use their splints four weeks following discharge from hospital. The main goals of choosing splints for both therapists and clients were prevention of contracture and deformity. The most indicated client reasons for adhering to the splint wearing program were therapist-related factors including clients’ trust and reliance on their therapists. Further reasons for clients implementing the recommended splint-wearing program and clinical implications are discussed.

Validity of the Waterlow screening tool and risks for pressure injury in acute care

Objectives: To assess the validity of the Waterlow screening tool in a cohort of internal medicine patients and to identify factors contributing to pressure injury. Design: Longitudinal cohort study Setting: A tertiary hospital in Brisbane, Australia Participants: 274 patients admitted through the Emergency Department or outpatient clinics and expected to remain in hospital for at least three days were included in the study. The mean age was 65.3 years. Interventions: Patients were screened on admission using the Waterlow screening tool. Every second day, their pressure ulcer status was monitored and recorded. Main outcome measures: Pressure ulcer incidence Results: Fifteen participants (5.5%) had an existing pressure ulcer and a further 12 (4.4%) developed a pressure ulcer during their hospital stay. Sensitivity of the Waterlow scale was 0.67, (95% CI: 0.35 to 0.88); specificity 0.79, (95% CI: 0.73 to 0.85); PPV 0.13, (95% CI: 0.07 to 0.24); NPV 0.98, (95% CI: 0.94 to 0.99). Conclusion: This study provides further evidence of the poor predictive validity of the Waterlow scale. A suitably powered randomised controlled trial is urgently needed to provide definitive evidence about the usefulness of the Waterlow scale compared with other screening tools and with clinical judgement.

Synthesis and thermal analysis of Indium based hydrotalcites of formula Mg6In2(CO3)(OH)16•4H2O

Insight into the unique structure of layered double hydroxides has been obtained using a combination of X-ray diffraction and thermal analysis. Indium containing hydrotalcites of formula Mg4In2(CO3)(OH)12•4H2O (2:1 In-LDH) through to Mg8In2(CO3)(OH)18•4H2O (4:1 In-LDH) with variation in the Mg:In ratio have been successfully synthesised. The d(003) spacing varied from 7.83 Å for the 2:1 LDH to 8.15 Å for the 3:1 indium containing layered double hydroxide. Distinct mass loss steps attributed to dehydration, dehydroxylation and decarbonation are observed for the indium containing hydrotalcite. Dehydration occurs over the temperature range ambient to 205 °C. Dehydroxylation takes place in a series of steps over the 238 to 277 °C temperature range. Decarbonation occurs between 763 and 795 °C. The dehydroxylation and decarbonation steps depend upon the Mg:In ratio. The formation of indium containing hydrotalcites and their thermal activation provides a method for the synthesis of indium oxide based catalysts.

Chemical and thermal properties of fractionated bagasse soda lignin

A major challenge of the 21st century will be to generate transportation fuels using feedstocks such as lignocellulosic waste materials as a substitute for existing fossil and nuclear fuels. The advantages of lignocellulosics as a feedstock material are that they are abundant, sustainable and carbon-neutral. To improve the economics of producing liquid transportation fuels from lignocellulosic biomass, the development of value-added products from lignin, a major component of lignocellulosics, is necessary. Lignins produced from black liquor through the fractionation of sugarcane bagasse with soda and organic solvents have been characterised by physical, chemical and thermal means. The soda lignin fractions have different physico-chemical and thermal properties from one another. Some of these properties have been compared to bagasse lignin extracted with aqueous ethanol.