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Heterogeneity is not always noise: lessons from improvement
1Institute for Healthcare Improvement, Cambridge, Massachusetts, USA. fdavidoff@cox.net
JAMA
|December 17, 2009
Summary
Participant heterogeneity is often suppressed in research to find intervention effects. This study explores why medicine struggles with heterogeneity and suggests methods to assess its impact on study outcomes.
Area of Science:
- Medical research methodology
- Clinical trial design
- Health services research
Background:
- Experimental methods aim to reduce participant variability (noise) to isolate intervention effects (signals).
- Over-suppressing participant heterogeneity can obscure crucial biological and clinical insights.
- Medical practice exhibits ambivalence towards participant heterogeneity's influence on outcomes, hindering its integration into clinical practice and research.
Purpose of the Study:
- To explore the origins of medicine's ambivalence regarding participant heterogeneity.
- To examine how healthcare improvement initiatives illuminate heterogeneity's impact on study methodologies.
- To propose methods for assessing heterogeneity's effect on study outcome measures.
Main Methods:
- Analysis of the evaluation of two health care improvement initiatives.
- Examination of unique features within improvement science.
- Exploration of methods to assess heterogeneity's influence on outcome measures.
Main Results:
- Healthcare improvement initiatives offer insights into managing participant heterogeneity.
- Specific features of improvement science can clarify heterogeneity's role in study outcomes.
- Methods for assessing heterogeneity's impact on outcome measures can be developed.
Conclusions:
- Understanding and incorporating participant heterogeneity is essential for robust medical research and practice.
- Improvement science provides a framework for addressing heterogeneity in clinical studies.
- Further development of methods to assess heterogeneity's effect on outcomes is warranted.
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