Modelling food and physical activity behaviours Philippe J. Giabbanelli

PJ GiabbanelliModelling food and physical activity behaviours1 Themes addressed Why would you use computational models? Novel ways to support public health modelling Modelling from physiology to social determinants

PJ Giabbanelli2 Why? Tell me what people will do in the future! Modelling food and physical activity behaviours

PJ Giabbanelli3 Why? Epstein (JASS 11(4):12) gives 16 reasons other than prediction to build models. Explaining Modelling food and physical activity behaviours To simulate far into the future, you need to understand what you have now and how it changes Explain 2 - Predict

PJ Giabbanelli4 Why? Epstein (JASS 11(4):12) gives 16 reasons other than prediction to build models. Explaining “Electrostatics explains lightning, but we cannot predict when or where the next bolt will strike.” Modelling food and physical activity behaviours A chaotic view of behavior change: a quantum leap for health promotion Resnicow & Vaughan, IJBNPA 2006

PJ Giabbanelli5 Why? Epstein (JASS 11(4):12) gives 16 reasons other than prediction to build models. Illuminate core dynamics We all have assumptions based on our personal experience. Models will make these assumptions explicit and can check for inconsistencies. Modelling food and physical activity behaviours

PJ Giabbanelli6 Why? Epstein (JASS 11(4):12) gives 16 reasons other than prediction to build models. « What if » Imagine that you want to intervene on the built environment. Would you try to change it and see whether it was a good idea? Using the computer, you create a virtual environment and see how virtual people react to changes. Modelling food and physical activity behaviours

And load up on antidepressants ?! 7

Food intake Exercise Peer behaviour Stress Obesity stigma SES PJ Giabbanelli8Modelling food and physical activity behaviours

PJ Giabbanelli9 From physiology to social determinants “There is increasing evidence that social influence and social network structures are significant factors in obesity.” Eating Exercising R.A. Hammond, Current Opinion in Endocrinology, Diabetes and Obesity 17, 467 (2010) Modelling food and physical activity behaviours

PJ Giabbanelli10 W. Rush, et al., Tech. rep NECSI 2003 Modelling food and physical activity behaviours From physiology to social determinants Rule: take the state shared by the majority of your friends. But I have only 2 friends! Well, I have 14 friends…

PJ Giabbanelli Everyone has the same number of friends Most people have few friends, few people have lots. (cellular automaton)(complex networks) D. Bahr, R. Browning, H. Wyatt, J. Hill, Exploiting social networks to mitigate the obesity epidemic, Obesity 17 (2009) Modelling food and physical activity behaviours From physiology to social determinants

PJ Giabbanelli12 StructureProcess How are individuals connected? = who interacts with who? How do individuals interact? = how people influence each other? Using a social network is key for realism. Using a majority rule would significantly oversimplify. Modelling food and physical activity behaviours From physiology to social determinants Small-worldScale-free

PJ Giabbanelli13Modelling food and physical activity behaviours From physiology to social determinants

PJ Giabbanelli14Modelling food and physical activity behaviours

PJ Giabbanelli15 From physiology to social determinants This example had a decent structure but modelled the process in simple ways. How can we better represent the context that shapes food and physical activity behaviours? Modelling food and physical activity behaviours

From physiology to social determinants PJ Giabbanelli16Modelling food and physical activity behaviours P-values Odds ratio ANOVA Besides, studies tend to speak on associations, not causations… ???

PJ Giabbanelli17 From physiology to social determinants I turned to experts on obesity and asked them to evaluate the strength of these causations. I built an expert system based on their feedback. Modelling food and physical activity behaviours

PJ Giabbanelli18 + From physiology to social determinants Modelling food and physical activity behaviours To be expanded thanks to funding of $46K from the Provincial Health Services Authority

PJ Giabbanelli19 From physiology to social determinants Modelling food and physical activity behaviours

PJ Giabbanelli20 Initialization MatchingSimulation James Marko Pablo Ali Nick From physiology to social determinants Modelling food and physical activity behaviours

PJ Giabbanelli21 Simulation Initialization Matching Influencing Influenced From physiology to social determinants James Marko Pablo Ali Nick Modelling food and physical activity behaviours

PJ Giabbanelli22 Initialization MatchingSimulation From physiology to social determinants James Marko Pablo Ali Nick Modelling food and physical activity behaviours

PJ Giabbanelli23 From physiology to social determinants Modelling food and physical activity behaviours Focusing on knowledge sharing… Comparing food labels Cooking healthy meals …are you better off following your friends or random people?

From physiology to social determinants ←probability of passing on knowledge→ ↑ Intensity of obesity ↓ PJ Giabbanelli24Modelling food and physical activity behaviours

From physiology to social determinants PJ Giabbanelli25Modelling food and physical activity behaviours What about behavioural responses to price fluctuations in food? What about the cost-effectiveness of interventions?

From physiology to social determinants PJ Giabbanelli26Modelling food and physical activity behaviours Individuals Socio-demographic variablesDecision making age gendereducationlocation beliefsprice taste accessibility Influencability by peers Food advertisement peers FABSocial network theory Pasadena, CA (USA) Parameter Data sources

From physiology to social determinants PJ Giabbanelli27Modelling food and physical activity behaviours Junk tax

Novel ways to support public health modelling PJ Giabbanelli28Modelling food and physical activity behaviours

Game activities Recommender System Practitioner’s office Interacting with peers Data about relevant psycho-social factors Data about similar peers provides improves Suggesting relevant questions Suggesting similar peers increases Conducting a targetted psycho- social assessment of patients queries refines Patients’ information ameliorates provides Completing surveys contributes to Self monitoring Builds on an evidence base to offer Improving health management PJ Giabbanelli29Modelling food and physical activity behaviours

Getting data Choosing a type of model Creating a conceptual model Creating & calibraing a computational model Analysing simulations Translate findings to stakeholders Novel ways to support public health modelling PJ Giabbanelli30Modelling food and physical activity behaviours

Getting data Choosing a type of model Creating a conceptual model Creating & calibraing a computational model Analysing simulations Translate findings to stakeholders Novel ways to support public health modelling PJ Giabbanelli31Modelling food and physical activity behaviours

Getting data Choosing a type of model Creating a conceptual model Creating & calibraing a computational model Analysing simulations Translate findings to stakeholders ? ? ? The support for modelling decreases as you progress to the more advanced stages We need to see how existing tools support this process, and develop guidelines to fill in the gaps Novel ways to support public health modelling PJ Giabbanelli32Modelling food and physical activity behaviours

1.PJ Giabbanelli, T Torsney-Weir, VK Mago. A fuzzy cognitive map of the psychosocial determinants of obesity. Applied Soft Computing 12(12): , PJ Giabbanelli, A Alimadad, V Dabbaghian, DT Finegood. Modeling the influence of social networks and environment on energy balance and obesity. Journal of Computational Science 3, 17-27, PJ Giabbanelli, P Jackson, DT Finegood. Modeling the joint effect of social determinants and peers on obesity. Intelligent Systems Reference Library (Springer) 52, PJ Giabbanelli, P Deck, L Andres, T Schiphorst, DT Finegood. Supporting a participant-centric management of obesity via a self-improving health game. Digital Human Modeling and Applications in Health, Safety, Ergonomics and Risk Management, Lecture Notes in Computer Science 8025: , PJ Giabbanelli. A novel framework for complex networks and chronic diseases. Studies in Computational Intelligence 424: , Dr Alimadad, Provincial Health Services Authority (CAN) Dr Mago Troy University (USA) Dr Jackson Simon Fraser U (CAN) Dr Finegood, President & CEO Michael Smith Foundation For Health Research (CAN) Dr Crutzen Maastricht U (Netherlands)

PJ GiabbanelliModelling food and physical activity behaviours We know: We do not know: One’s threshold of influence to trigger changes The structure of the population By how much one’s food consumption can change By how much population weight changes in a year

PJ Giabbanelli Simulating interventions on food intake and exercise for different cases of obese patients. From physiology to social determinants Modelling food and physical activity behaviours

PJ GiabbanelliModelling food and physical activity behaviours

PJ GiabbanelliModelling food and physical activity behaviours