• Goodson Chapter 7• Resnicow & Page, 2008• Krieger, 1994

Pattern 3: Deliberate Privileging of Linearity: The Whole or the Sum of the Parts?

Goodson, P. (2010). Theory in Health Promotion Research and Practice. Mississauga, Ontario: Jones and Bartlett Publishers.

Limitations of Linear Theories

• Focus on the individual• Focus on cognitive factors• “the whole is equal to the sum of its parts”

“this orderly, linear framework remains the mainstream foundation of the human and social sciences to this day.” (Cooper & Geyer, 2008)

Complexity Theories

• Offer a non-linear way to explain unpredictability, complexity, and dynamic aspects of behavior

• “Complex Adaptive Systems (CASs) consist of a set of interacting elements that are able to change and adapt in multiple ways (Zimmerman, Lindberg, & Plsek, 1998).”

Complexity Theories

1. Whole is more than the sum of its parts

2. CASs comprise other CASs

3. Agents within CASs evolve

4. Sustainability depends on diversity

5. Decentralized, or “distributed” control

6. Size of output does not necessarily correspond to size of input

7. Dependence on original conditions (“Butterfly Effect”)

8. CASs drawn to attractors9. Unpredictable behavior10. Order to the chaos

What are Attractors?

Examples

• School district• Puzzle• Others?

Challenges in practice:Allowing a system to self-organize?Recognizing how behavior itself influences the

system?

Goodson Chapter 7

• Empirical evidence• Statistical implications• Cautions

Embracing Chaos and Complexity: A Quantum Change for Public Health

Resnicow, K. and Page, S.E. (2008). American Journal of Public Health, Vol 98, No. 8, pp. 1382-1389.

Resnicow & Page, 2008

• Propose that the linear paradigm is flawed• Key Principles:–Quantum behavior change–Chaotic process, sensitive to initial

conditions–Occurs within CASs

Quantum Change

• Wave/particle• Dramatic experience OR• Sudden insight (Miller)• Can occur with little input

Initial Conditions

• Butterfly Effect• Infinite permutations• Fractal patterns• Identification of fractals suggests

intervention points

Change as a CAS

• “particle components of a motivational quantum” = different starting points• Multiple pathways• “lever points” or “tipping points”

Implications for Public Health

• Identification of leverage points• Consideration of timing and initial

conditions• View behavior as probabilistic

• Encourage “wing flapping”?

Resnicow & Page, 2008

• Empirical evidence• Statistical implications

Unify Linear and Complex?

Resnicow & Page, 2008

• Practical implications–Repeated exposures–Understand individual “receptivity”

(sounds familiar)–Lower upper limit on variance

explained

Resnicow & Page, 2008

• Potential areas of research–Qualitative methods–Quantitative methods–Physiological mechanism studies–Agent-based and computational

modeling

Epidemiology and the web of causation: Has anyone seen the spider?

Krieger, N. (1994). Soc. Sci. Med. Vol. 39, No. 7, pp. 887-903

Epidemiologic Theory

• Web of Causation and multivariate analyses• “paucity of critical reflection”• Insufficient preparation of new

epidemiologists

Web of Causation MacMahon, Pugh, Ibsen (1960) as a challenge to “chain of causation”

Web of Causation

• Increased understanding of interaction and confounding

• Rothman

Problems with Web

• Omitted discussion of origins • Lacks discussion of theory for the model• Focus on proximal factors• Does not distinguish between individuals and

populations• “biomedical individualism”

Modern Contributions

• “environment” ill-defined (Vanderbroucke)• Resurgence of single agent theory• McKeown’s etiologic groups• Social determinants• Conclusion: Epi still lacking an ecosocial theory

Ecosocial Framework

• How to use epidemiological data• Greater precision in etiology• Better definitions of “lifestyle”• Challenge to current definition of

“environment”• Challenge to rigid distinctions of individual and

group level analyses