We suggest that the authors1 are confusing the concepts of complicated and complex in both the nature of the intervention and the nature of the context and landscape of the intervention.2
According to Glouberman and Zimmerman3 systems can be understood as being simple, complicated, complex, or chaotic. Simple and complicated systems or processes are related to separate entities or discrete activities. In contrast complex systems are based on relationships, and their properties of self-organisation, interconnectedness and evolution. Research into complex systems demonstrates that they cannot be understood solely by simple or complicated approaches to evidence, policy, planning and management.4
Simple problems, such as following a protocol, may encompass some basic issues of technique and terminology, but once these are mastered, following the "recipe" carries with it a very high assurance of success.3
Complicated problems contain subsets of simple problems but are not merely reducible to them. Their complicated nature is often related not only to the scale of a problem like open heart surgery, but also to issues of coordination or specialised expertise. Complicated problems, although their solutions are generalisable, are not simply an assembly of simple components.3
Complex problems can encompass both complicated and simple subsidiary problems, but are not reducible to either, as they too have special requirements, including an understanding of unique local conditions and their historical pathways. 3 Adaptive, self-organising social networks produce observable patterns in response to interventions, that are neither predictable nor generalisable, yet understanding them in retrospect can inform future possibilities.2
Approaches to understanding complex systems developed by Kurtz and Snowden5 for IBM international e-business management have been successfully applied with frontline health care providers.6 They categorise activities on four levels of knowledge and organisation--described as the known, the knowable, the complex and the chaotic. We argue that each is governed by a particular evidence and decision-making mode: the known (analytical/reductionist evidence-based care); the knowable (potentially ascertainable by application of evidence-based methods) and the complex (non-predictable, but potentially understandable by pattern observation) knowledge domains. The known and knowable refer mainly to simple and complicated knowledge, while complex (and chaotic) knowledge is based on understanding dynamic system patterns in which the whole is greater than the sum of the known and knowable parts.
Thus, methodology described by Campbell et al as complex intervention(s) in complex health systems should really be described as interventions and RCTs based upon the assumptions of complicated interventions in known or knowable environments. The purpose of RCTs is to compare two or more options and control for all differences, such that in future one can predict which option to implement. The approach described seeks to reduce what is complex to a complicated series of steps and processes in order to ensure greater replicability and generalisability which is laudable. Such approaches are a considerable improvement on the black box RCT of the past, yet it is misleading to use the terminology of complexity. Arguably there have been sufficient international journal articles on the subject of complexity for the meaning to have become common7.
1. Campbell NC, Murray E, Darbyshire J, Emery J, Farmer A, Griffiths F, et al. Designing and evaluating complex interventions to improve health care. British Medical Journal 2007;334(7591):455-459.
2. Martin C, Sturmberg J. General Practice - chaos, complexity and innovation. Medical Journal of Australia 2005;183(2):106-109.
3. Glouberman S, Zimmerman B. Complicated and Complex Systems: What Would Successful Reform of Medicare Look Like? Ottawa: Discussion paper No 8. Commission on the Future of Health Care in Canada, 2002.
4. Bar-Yam Y. System Care: Multiscale analysis of Medical Errors - Eliminating errors and improving organizational capabilities. NECSI Technical Report 2004-09-01, New England Complex Systems Institute 2004:http://necsi.org/projects/yaneer/NECSITechnicalReport2004-09.pdf (accessed 12-03-05).
5. Kurtz C, Snowden D. The new dynamics of strategy: Sense-making in a complex and complicated world. IBM Systems Journal 2003;42(3):462-483.
Rapid Response:
Confusing the concepts of complicated and complex
We suggest that the authors1 are confusing the concepts of complicated and complex in both the nature of the intervention and the nature of the context and landscape of the intervention.2
According to Glouberman and Zimmerman3 systems can be understood as being simple, complicated, complex, or chaotic. Simple and complicated systems or processes are related to separate entities or discrete activities. In contrast complex systems are based on relationships, and their properties of self-organisation, interconnectedness and evolution. Research into complex systems demonstrates that they cannot be understood solely by simple or complicated approaches to evidence, policy, planning and management.4
Simple problems, such as following a protocol, may encompass some basic issues of technique and terminology, but once these are mastered, following the "recipe" carries with it a very high assurance of success.3
Complicated problems contain subsets of simple problems but are not merely reducible to them. Their complicated nature is often related not only to the scale of a problem like open heart surgery, but also to issues of coordination or specialised expertise. Complicated problems, although their solutions are generalisable, are not simply an assembly of simple components.3
Complex problems can encompass both complicated and simple subsidiary problems, but are not reducible to either, as they too have special requirements, including an understanding of unique local conditions and their historical pathways. 3 Adaptive, self-organising social networks produce observable patterns in response to interventions, that are neither predictable nor generalisable, yet understanding them in retrospect can inform future possibilities.2
Approaches to understanding complex systems developed by Kurtz and Snowden5 for IBM international e-business management have been successfully applied with frontline health care providers.6 They categorise activities on four levels of knowledge and organisation--described as the known, the knowable, the complex and the chaotic. We argue that each is governed by a particular evidence and decision-making mode: the known (analytical/reductionist evidence-based care); the knowable (potentially ascertainable by application of evidence-based methods) and the complex (non-predictable, but potentially understandable by pattern observation) knowledge domains. The known and knowable refer mainly to simple and complicated knowledge, while complex (and chaotic) knowledge is based on understanding dynamic system patterns in which the whole is greater than the sum of the known and knowable parts.
Thus, methodology described by Campbell et al as complex intervention(s) in complex health systems should really be described as interventions and RCTs based upon the assumptions of complicated interventions in known or knowable environments. The purpose of RCTs is to compare two or more options and control for all differences, such that in future one can predict which option to implement. The approach described seeks to reduce what is complex to a complicated series of steps and processes in order to ensure greater replicability and generalisability which is laudable. Such approaches are a considerable improvement on the black box RCT of the past, yet it is misleading to use the terminology of complexity. Arguably there have been sufficient international journal articles on the subject of complexity for the meaning to have become common7.
1. Campbell NC, Murray E, Darbyshire J, Emery J, Farmer A, Griffiths F, et al. Designing and evaluating complex interventions to improve health care. British Medical Journal 2007;334(7591):455-459.
2. Martin C, Sturmberg J. General Practice - chaos, complexity and innovation. Medical Journal of Australia 2005;183(2):106-109.
3. Glouberman S, Zimmerman B. Complicated and Complex Systems: What Would Successful Reform of Medicare Look Like? Ottawa: Discussion paper No 8. Commission on the Future of Health Care in Canada, 2002.
4. Bar-Yam Y. System Care: Multiscale analysis of Medical Errors - Eliminating errors and improving organizational capabilities. NECSI Technical Report 2004-09-01, New England Complex Systems Institute 2004:http://necsi.org/projects/yaneer/NECSITechnicalReport2004-09.pdf (accessed 12-03-05).
5. Kurtz C, Snowden D. The new dynamics of strategy: Sense-making in a complex and complicated world. IBM Systems Journal 2003;42(3):462-483.
6. Hoff T. The power of frontline workers in transforming organizations. The Upstate New York Veteran’s Health Administration: IBM Center for Healthcare Management, 2003: Available at: http://www-935.ibm.com/services/us/gbs/bus/pdf/ibm_healthcaremanagement_... (accessed Jul 2007).
7. Plsek PE, Greenhalgh T. Complexity science: The challenge of complexity in health care. BMJ. 2001 Sep 15;323(7313):625-8
Competing interests:
None declared
Competing interests: No competing interests