Internal validation of models for predicting paediatric survival and trends in serious paediatric hospitalised injury in Australia

International Classification of Disease based Injury Severity Score (ICISS): a comparison of methodologies applied to linked data from New South Wales, Australia

BACKGROUND

The International Classification of Disease Injury Severity Score (ICISS) provides an efficient method to determine injury severity in hospitalised injury patients. Injury severity metrics are of particular interest for the tracking of road transport injury rates and trends. The aims of this study were to calculate ICISS using linked morbidity and mortality datasets and to compare predictive ability of various methods and metrics.

METHODS

This was a retrospective analysis of Admitted Patient Data Collection records from New South Wales, Australia, linked with mortality data. Using a split sample approach, design data (2008-2014; n=1 035 174 periods of care) was used to derive survival risk ratios and calculate various ICISS scales based on in-hospital death and 3-month death. These scales were applied to testing data (2015-2017; n=575 306). Logistic regression modelling was used to determine model discrimination and calibration.

RESULTS

There were 12 347 (1.19%) in-hospital deaths and 29 275 (2.83%) 3-month deaths in the design data. Model discrimination ranged from acceptable to excellent (area under the curve 0.75-0.88). Serious injury (ICISS≤0.941) rates in the testing data varied, with a range of 10%-31% depending on the methodology. The 'worst injury' ICISS was always superior to 'multiplicative injury' ICISS in model discrimination and calibration.

CONCLUSIONS

In-hospital death and 3-month death were used to generate ICISS; the former is recommended for settings with a focus on short-term threat to life, such as in trauma care settings. The 3-month death approach is recommended for outcomes beyond immediate clinical care, such as injury compensation schemes.

Changes in Paediatric Injury-Related Emergency Department Presentations during the COVID-19 Pandemic

This study aimed to quantify changes in paediatric injury-related Emergency Department (ED) presentations at a large metropolitan paediatric hospital during the first two years of the COVID-19 pandemic (i.e., 2020 and 2021). This retrospective cohort study included children aged ≤15 years who presented to the ED at the Children’s Hospital at Westmead, Sydney, New South Wales, Australia, with a principal diagnosis of injury during 1 January 2010 to 31 December 2021. Annual and monthly incidence of paediatric injury-related ED presentations from 2010 to 2019 were used to fit autoregressive integrated moving average models, from which forecast estimates with 95% prediction intervals were derived and compared against corresponding observed values to obtain estimates of absolute and relative forecast errors. The distributions of injuries by injury severity in 2020 and 2021 were compared against the 2010–2019 reference period. The annual incidence of paediatric injury-related ED presentations was 7.6% and 4.7% lower than forecasted in 2020 and 2021, respectively, equating to an estimated total of 1683 fewer paediatric injury-related ED presentations during the two-year period. The largest reductions in monthly incidence of paediatric injury-related ED presentations were observed during the periods of major societal restrictions (i.e., March–May 2020 and July–October 2021). Significant reductions in monthly incidence of injury-related ED presentations were observed for minor injuries only, with no discernable reductions in moderate and serious injuries. These findings highlight the impact of the COVID-19 pandemic on paediatric injury-related ED presentations and the need for future epidemiological studies examining secular trends in paediatric trauma volumes to account for the impact of the COVID-19 pandemic.

Hospital service use following an injury hospitalisation for young males and females in a population-level matched retrospective cohort study

BACKGROUND

Children and young people who sustain injuries resulting in a hospital admission may experience adverse effects for months or years following the event. Understanding the attributable burden and health service needs is vital for public health planning as well as individual care provision. This study aims to identify the hospitalised morbidity associated with injury among young people by sex using a population-level matched cohort.

METHOD

A population-level matched case-comparison retrospective cohort study of young people aged ≤18 years hospitalised for an injury during 2005-2018 in New South Wales, Australia using linked birth, health, and mortality records. The comparison cohort was matched on age, gender and residential postcode. Adjusted rate ratios (ARR) were calculated for age group, injury severity and nature of injury by sex.

RESULTS

There were 122,660 (60.9%) males and 78,712 (39.1%) females aged ≤18 years hospitalised after sustaining an injury. Males (ARR 2.89; 95%CI 2.81-2.97) and females (ARR 2.79; 95%CI 2.68-2.90) who were hospitalised after an injury had a higher risk of subsequent hospital admission than their matched peers. Males (ARR 3.38; 95%CI 2.81-4.05) and females (ARR 3.41; 95%CI 2.72-4.26) with serious injuries had a higher risk of admission compared to peers. Males with dislocations, sprains and strains (ARR 3.40; 95%CI 3.03-3.82), burns (ARR 3.37; 95%CI 2.99-3.80), and fractures (ARR 3.20; 95%CI 3.07-3.33), and females with burns (ARR 3.84; 95%CI 3.40-4.33), dislocations, sprains and strains (ARR 3.54; 95%CI 2.96-4.23), and traumatic brain injury (ARR 3.39; 95%CI 3.01-3.82) had the highest risk of subsequent hospitalisation compared to peers.

CONCLUSION

Patient management and care extends beyond the injury admission as many young people face high levels of contact with health services in the months and years following injury. These findings will inform health service planning and trauma care management for young people and families affected by injury.

Incidence, Trends, and Seasonality of Paediatric Injury-Related Emergency Department Presentations at a Large Level 1 Paediatric Trauma Centre in Australia

This retrospective cohort study aimed to examine the characteristics, incidence, temporal trends, and seasonality of paediatric injury-related Emergency Department (ED) presentations at a large metropolitan paediatric hospital. It included children aged ≤15 years who presented to the ED at The Children’s Hospital at Westmead, Sydney Australia, with a principal diagnosis of injury during the ten-year period from 1 January 2010 to 31 December 2019. Descriptive statistics were used to describe the characteristics of the cohort and the distribution of ED presentations by mode of arrival, triage category, discharge status, injury diagnosis. Negative binomial regression was used to examine percentage change in annual incidence. Seasonality was examined with Seasonal and Trend decomposition using Loess (STL). There were 134,484 (59.7% male children) paediatric injury-related ED presentations during the ten-year period, of which 23,224 (17.3%) were admitted to hospital. Head injury accounted for more than one-quarter (26.8%) of ED presentations. The average annual increase in incidence was more pronounced during the first five years (5.6% [95%CI 4.1% to 7.1%]) than in the last five years (0.8% [95%CI 0.2% to 1.5%]). The monthly incidence of ED presentations had a bimodal distribution with peaks during autumn (March–May) and spring (October–November) seasons. The mean number of ED presentations per day was higher on weekends (40.8 ± 0.3) than weekdays (35.3 ± 0.8). During 2010 to 2019, there was a significant increase in the annual incidence of injury-related ED presentations for children aged ≤15 years, with head injury accounting for more than one-quarter of the ED presentations. The incidence of paediatric injury-related ED presentations was higher during autumn and spring seasons and at weekends. These data will inform health resource planning and priority-setting and advocacy for child injury prevention strategies in Australia.

Comparative analysis of off-road vehicle crashes in children: motorcycles versus quad bikes

OBJECTIVE

To characterise and compare off-road motorcycle and quad bike crashes in children in New South Wales (NSW), Australia.

METHODS

A retrospective, cross-sectional study was performed of children aged 0-16 years, admitted to hospitals in NSW, from 2001 to 2018 following an injury sustained in an off-road motorcycle or quad bike crash, using linked hospital admissions, mortality and census data.Motorcycle and quad bike injuries were compared regarding: demographics; incidence; body region injured and type of injury; injury severity based on the survival risk ratio; length of stay and mortality.

RESULTS

There were 6624 crashes resulting in hospitalisation; 5156 involving motorcycles (77.8%) and 1468 involving quad bikes (22.2%). There were 10 fatalities (6 from motorcycles and 4 from quad bikes). The rates of injury declined over the study period for motorcycles, but not for quad bikes.Motorcycle riders were more likely than quad bike riders to have lower limb injuries (OR 1.49, p<0.001) but less likely to have head/neck (OR 0.616, p<0.001), abdominal (OR 0.778, p=0.007) and thoracic (OR 0.745, p=0.003) injuries. Quad bike crashes resulted in higher injury severity (mean International Classification Injury Severity Score 0.975 vs 0.977, p=0.03) and longer hospital stay (mean 2.42 days vs 2.09 days, p=0.01).

CONCLUSIONS

There are significant differences between quad bike and motorcycle crashes in injury type and affected body region. While quad bike injuries in children were more severe, there were almost four times more hospitalisations from motorcycles overall. The overall larger burden of motorcycle crashes suggests a greater focus of injury prevention countermeasures for two-wheeled riders is needed.

International classification of disease based injury severity score (ICISS): A data linkage study of hospital and death data in Victoria, Australia

BACKGROUND

Surveillance of severe injury incidence and prevalence using ICD-based injury severity scores (ICISS) requires valid, locally applicable diagnosis-specific survival probabilities (DSPs). This study aims to derive and validate ICISS in Victoria, Australia, and compare various ICISS methodologies in terms of accuracy and calculated severe injury prevalence.

METHODS

This study used injury admissions (ICD-10-AM coded) from the Victorian Admitted Episodes Database (VAED) linked with death data (Cause of Death - Unit Record Files: CODURF). Using design data (July 2008 - June 2014; n = 720,759), various ICISS scales were derived, based on (i) in-hospital and (ii) three-month mortality. These scales were applied to testing data (July 2014 - December 2016; n = 334,363). Logistic regression modelling was used to determine model discrimination and calibration.

RESULTS

In the design data, there were 6,337(0.9%) hospital deaths and 17,514(2.4%) three-months deaths; in the testing data, there were 2,700(0.8%) hospital deaths and 8,425(2.5%) three-month deaths. Newly developed ICISS scales had acceptable to outstanding discrimination, with Area Under the Curve ranging from 0.758 to 0.910. Age-specific ICISS scales were superior to general ICISS scales in model discrimination but inferior in model calibration. Calculated severe injury (ICISS ≤0.941) prevalence in the testing data ranged from 2% to 24%, depending on which mortality outcomes were used to calculate DRGs.

CONCLUSIONS

This study provides local, validated ICISS scores that can be used in Victoria. It is recommended that age group stratified ICISS based on the worst-injury method is used. From the comparison of various ICISS scores, reflecting the range of ICISS permutations that are currently in use, care should be taken to compare ICISS methodology before comparing severe injury prevalence per population, injury cause, and time trends.

The impact of childhood injury and injury severity on school performance and high school completion in Australia: a matched population-based retrospective cohort study

Background

Exploring the impact of injury and injury severity on academic outcomes could assist to identify characteristics of young people likely to require learning support services. This study aims to compare scholastic performance and high school completion of young people hospitalised for an injury compared to young people not hospitalised for an injury by injury severity; and to examine factors influencing scholastic performance and school completion.

Method

A population-based matched case-comparison cohort study of young people aged ≤18 years hospitalised for an injury during 2005–2018 in New South Wales, Australia using linked birth, health, education and mortality records. The comparison cohort was matched on age, gender and residential postcode. Generalised linear mixed modelling examined risk of performance below the national minimum standard (NMS) on the National Assessment Plan for Literacy and Numeracy (NAPLAN) and generalised linear regression examined risk of not completing high school for injured young people compared to matched peers.

Results

Injured young people had a higher risk of not achieving the NMS compared to their matched peers for numeracy (ARR: 1.12; 95%CI 1.06–1.17), reading (ARR: 1.09; 95%CI 1.04–1.13), spelling (ARR: 1.13; 95%CI 1.09–1.18), grammar (ARR: 1.11; 95%CI 1.06–1.15), and writing (ARR: 1.07; 95%CI 1.04–1.11). As injury severity increased from minor to serious, the risk of not achieving the NMS generally increased for injured young people compared to matched peers. Injured young people had almost twice the risk of not completing high school at year 10 (ARR: 2.17; 95%CI 1.73–2.72), year 11 (ARR: 1.95; 95%CI 1.78–2.14) or year 12 (ARR: 1.93; 95%CI 1.78–2.08) compared to matched peers.

Conclusions

The identification of characteristics of young people most likely to encounter problems in the academic environment after sustaining an injury is important to facilitate the potential need for learning support. Assessing learning needs and monitoring return-to-school progress post-injury may aid identification of any ongoing learning support requirements.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02891-x.