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Intensive Care Medicine

Published in:

01-09-2005 | Review

Studying outcomes of intensive care unit survivors: measuring exposures and outcomes

Authors: Dale M. Needham, David W. Dowdy, Pedro A. Mendez-Tellez, Margaret S. Herridge, Peter J. Pronovost

Published in: Intensive Care Medicine | Issue 9/2005

Abstract

Background

Measurement of long-term outcomes and the patient and intensive care unit (ICU) factors predicting them present investigators with unique challenges. There is little systematic guidance for measuring these outcomes and exposures within the ICU setting. As a result measurement methods are often variable and noncomparable across studies.

Methods

We use examples from the critical care literature to describe measurement as it relates to three key elements of clinical studies: subjects, outcomes and exposures, and time. Using this framework we review the principles and challenges of measurement and make recommendations for long-term outcomes research in the field of critical care medicine.

Discussion

Relevant challenges discussed include: (a) selection bias and heterogeneity of ICU research subjects, (b) appropriate selection and measurement of outcome and exposure variables, and (c) accounting for the effect of time in the exposure-outcome relationship, including measurement of baseline data and time-varying variables.

Conclusions

Addressing these methodological challenges will advance research aimed at improving the long-term outcomes of ICU survivors.

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Title: Studying outcomes of intensive care unit survivors: measuring exposures and outcomes
Authors: Dale M. Needham
David W. Dowdy
Pedro A. Mendez-Tellez
Margaret S. Herridge
Peter J. Pronovost
Publication date: 01-09-2005
Publisher: Springer-Verlag
Published in: Intensive Care Medicine / Issue 9/2005
Print ISSN: 0342-4642
Electronic ISSN: 1432-1238
DOI: https://doi.org/10.1007/s00134-005-2656-7

At a glance: The STEP trials

Springer Medicine

Studying outcomes of intensive care unit survivors: measuring exposures and outcomes

Abstract

Background

Methods

Discussion

Conclusions

At a glance: The STEP trials

Springer Medicine

Abstract

Background

Methods

Discussion

Conclusions

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