Implications of estimating road traffic serious injuries from hospital data

Abstract

To determine accurately the number of serious injuries at EU level and to compare serious injury rates between different countries it is essential to use a common definition. In January 2013, the High Level Group on Road Safety established the definition of serious injuries as patients with an injury level of MAIS3+(Maximum Abbreviated Injury Scale). Whatever the method used for estimating the number or serious injuries, at some point it is always necessary to use hospital records. The aim of this paper is to understand the implications for (1) in/exclusion criteria applied to case selection and (2) a methodological approach for converting ICD (International Classification of Diseases/Injuries) to MAIS codes, when estimating the number of road traffic serious injuries from hospital data. A descriptive analysis with hospital data from Spain and the Netherlands was carried out to examine the effect of certain choices concerning in- and exclusion criteria based on codes of the ICD9-CM and ICD10. The main parameters explored were: deaths before and after 30 days, readmissions, and external injury causes. Additionally, an analysis was done to explore the impact of using different conversion tools to derive MAIS3 + using data from Austria, Belgium, France, Germany, Netherlands, and Spain. Recommendations are given regarding the in/exclusion criteria and when there is incomplete data to ascertain a road injury, weighting factors could be used to correct data deviations and make more real estimations.

The reliability of the ICD-AIS map in identifying serious road traffic injuries from the Helsinki Trauma Registry

“…Similar results to our study have also been presented earlier by Pérez et al [6] who compared the number of MAIS 3+ patients between the ICD-AIS map by AAAM and direct AIS coding. They used a German data set (n = 209) and concluded that the ICD-AIS map underestimated the amount of seriously injured patients by 20% [6], which is nearly the same figure as ours. However, they used a German version of ICD-10 (ICD-10-GM) which is, to some extent, more specific than the ICD-10 used in Finland.…”

“…However, they used a German version of ICD-10 (ICD-10-GM) which is, to some extent, more specific than the ICD-10 used in Finland. In general, several studies indicate that different kinds of automatic ICD-AIS conversion tools generates rather lower than higher numbers of serious injuries than direct AIS coding [6,[14][15][16]. The reliability of input data, and more specifically, the quality and accuracy of ICD injury coding, is essential for the successful conversion and has a significant impact on the results.…”

“…The reliability of input data, and more specifically, the quality and accuracy of ICD injury coding, is essential for the successful conversion and has a significant impact on the results. Pérez et al [6] have made recommendations on how to address the challenges of inadequate data.…”

“…The same problem emerged in the present study. Pérez et al [6] have also concluded that because most European countries use an older version of ICD-10 without clinical modification (CM), the conversion table does not fit well with European practice. As in the previous study, misclassifications appeared frequently in the injuries of visceral organs such as major ruptures, in open fractures of extremities, and in specific head injuries with prolonged unconsciousness.…”

“…In addition to the conversion tool of AAAM, there are several other tools for generating ICD injury codes to AIS [6]. Some of them also generate Injury Severity Score (ISS) codes [7] and New Injury Severity Score (NISS) codes [8], which are AIS derivatives.…”