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All Patient Refined-Diagnosis Related Groups’ (APR-DRGs) Severity of Illness and Risk of Mortality as predictors of in-hospital mortality

  • Health Policy
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Abstract

The aims of this study were to assess All-Patient Refined Diagnosis-Related Groups’ (APR-DRG) Severity of Illness (SOI) and Risk of Mortality (ROM) as predictors of in-hospital mortality, comparing with Charlson Comorbidity Index (CCI) and Elixhauser Comorbidity Index (ECI) scores. We performed a retrospective observational study using mainland Portuguese public hospitalizations of adult patients from 2011 to 2016. Model discrimination (C-statistic/ area under the curve) and goodness-of-fit (R-squared) were calculated. Our results comprised 4,176,142 hospitalizations with 5.9% in-hospital deaths. Compared to the CCI and ECI models, the model considering SOI, age and sex showed a statistically significantly higher discrimination in 49.6% (132 out of 266) of APR-DRGs, while in the model with ROM that happened in 33.5% of APR-DRGs. Between these two models, SOI was the best performer for nearly 20% of APR-DRGs. Some particular APR-DRGs have showed good discrimination (e.g. related to burns, viral meningitis or specific transplants). In conclusion, SOI or ROM, combined with age and sex, perform better than more widely used comorbidity indices. Despite ROM being the only score specifically designed for in-hospital mortality prediction, SOI performed better. These findings can be helpful for hospital or organizational models benchmarking or epidemiological analysis.

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Authors and Affiliations

  1. MEDCIDS – Department of Community Medicine, Information and Health Decision Sciences, Faculty of Medicine, University of Porto, Porto, Portugal

    João Vasco Santos, João Viana, Júlio Souza, Fernando Lopes & Alberto Freitas

  2. CINTESIS – Centre for Health Technology and Services Research, Porto, Portugal

    João Vasco Santos, João Viana, Júlio Souza, Fernando Lopes & Alberto Freitas

  3. Public Health Unit, ACES Grande Porto VIII – Espinho/Gaia, ARS Norte, Vila Nova de Gaia, Portugal

    João Vasco Santos

  4. NOVA National School of Public Health, Universidade NOVA de Lisboa, Lisboa, Portugal

    João Vasco Santos

  5. Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal

    Carla Pinto

  6. NOVA National School of Public Health, Public Health Research Centre, Universidade NOVA de Lisboa, Lisboa, Portugal

    Sílvia Lopes

  7. Comprehensive Health Research Center, Lisboa, Portugal

    Sílvia Lopes

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  1. João Vasco Santos
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Correspondence to João Vasco Santos.

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Santos, J.V., Viana, J., Pinto, C. et al. All Patient Refined-Diagnosis Related Groups’ (APR-DRGs) Severity of Illness and Risk of Mortality as predictors of in-hospital mortality. J Med Syst 46, 37 (2022). https://doi.org/10.1007/s10916-022-01805-3

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