Surrogate Measures of Patient-centered Outcomes in Critical Care

  • Rubenfeld G.D. 
Conference paper
Part of the Update in Intensive Care Medicine book series (UICMSOFT, volume 39)


The ultimate goal of medicine is to improve health in ways that matter to patients. A variety of outcomes are important to patients: symptoms, quality of life, duration of life, quality of dying, the effect of their health care on their loved ones, and the cost of medical care. Because of the importance of these outcomes to patients they are referred to as ‘patient-centered’ outcomes. Ideally, chnicians will offer, insurers will pay for, and patients will have the opportunity to use treatments that have been shown to improve patient-centered outcomes. Patient-centered outcomes are dis- tinct from any number of chemical, physiologic, and radiographic variables that may be measured in clinical research. There are many reasons investigators choose to measure these important alternate or auxiliary measures. They often provide essential information about how a treatment works, about complications, and about the study population and subgroups. However, when one of these variables is used specifically as a substitute for a patient-centered outcome, it is referred to as a surrogate outcome variable. Other synonyms for these variables are interme- diate ox proxy outcome variables [2]. Common examples of surrogate outcomes are substituting blood pressure for survival in a study of antihypertensives, left ventricular function for quality of life in a study of therapy for congestive heart failure, and tumor size for survival in a study of cancer therapy.


Critical Care Acute Respiratory Distress Syndrome Critical Illness Human Growth Hormone Surrogate Outcome 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Rubenfeld G.D. 
    • 1
  1. 1.Division of Pulmonary and Critical Care Medicine Harborview Medical CenterUniversity of WashingtonSeattleUSA

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