Calc Function

    • Calcs that help predict probability of a diseaseDiagnosis
    • Subcategory of 'Diagnosis' designed to be very sensitiveRule Out
    • Disease is diagnosed: prognosticate to guide treatmentPrognosis
    • Numerical inputs and outputsFormula
    • Med treatment and moreTreatment
    • Suggested protocolsAlgorithm





    Chief Complaint


    Organ System


    Patent Pending

    Injury Severity Score (ISS)

    Standardizes severity of traumatic injury based on worst injury of 6 body systems.
    When to Use
    The ISS attempts to standardize trauma severity to help trauma centers predict outcomes.
    When calculating the ISS manually, there are two steps (see Formula). An experienced trauma provider should rate the severity of each body system injury.


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    Next Steps
    Creator Insights


    As in all trauma patients, initial strategy should focus on the primary and secondary survey and assessing and stablilizing the ABCs.


    Each of the six body systems' injuries are given an Abbreviated Injury Scale (AIS); the most severe injury in each body system is used for the Injury Severity Score. Next, the three highest AIS scores are squared, then summed to determine a patient's Injury Severity Score (ISS), which ranges from 0-75. If a patient has an “Unsurvivable” injury in any of the body systems, they are automatically assigned a score of 75.

    Dr. Susan Baker

    About the Creator

    Susan Baker, MPH, is an professor and epidemiologist specializing in injury prevention at Johns Hopkins Bloomberg School of Public Health and was the first director of the Center for Injury Research and Policy. She is well known for authoring the Injury Fact Book. Professor Baker's teaching and research is aimed at influencing policy changes that will reduce the likelihood of injury for thousands of people.

    To view Dr. Susan Baker's publications, visit PubMed