Universitätsklinikum Hamburg-Eppendorf (UKE) Zentrum für Psychosoziale Medizin Institut und Poliklinik für Medizinische Psychologie Director: Prof. Dr. med. Dr. phil. Dipl.-Psych. Martin Härter Health Behaviour Change – Theories and Models Current application and future directions for reliable health behavior change Dissertation zur Erlangung des Grades eines Doktors der Medizin an der Medizinischen Fakultät der Universität Hamburg. vorgelegt von: Dominik Dotzauer aus Berlin Hamburg 2017 1 Angenommen von der Medizinischen Fakultät der Universität Hamburg am: 12.01.2018 Veröffentlicht mit Genehmigung der Medizinischen Fakultät der Universität Hamburg. Prüfungsausschuss, der Vorsitzende: Prof. Dr. Karl-Heinz Schulz Prüfungsausschuss, zweite Gutachterin: PD Dr. Birgit-Christiane Zyriax 2 1 Table of Contents 1 Table of Contents ............................................................................................ 3 2 Working Hypothesis and Guiding Questions .................................................... 6 3 Introduction ...................................................................................................... 7 4 Background ...................................................................................................... 8 4.1 Lifestyle: cause and cure ........................................................................... 9 4.2 Why Health Behavior Change (HBC) ...................................................... 10 4.3 “Why is it so difficult?”: The Challenge of changing health behavior ....... 10 4.4 Theories and models of health behavior change ..................................... 11 5 Methods ......................................................................................................... 12 5.1 A data driven process to select theories .................................................. 12 5.2 Step 1: Selecting Health Behavior Change Theories from research ....... 14 5.3 Step 2: Proxy Markers ............................................................................. 16 5.4 Evidence from a scoping review .............................................................. 28 5.5 Selected Theories ................................................................................... 28 6 Presentation of the HBCTs ............................................................................ 30 6.1 The Theory of Planned Behavior (TPB) .................................................. 31 6.1.1 Usefullness of the TPB ..................................................................... 32 6.1.2 Limitations of the TPB ....................................................................... 33 6.1.3 Conclusion ........................................................................................ 39 6.2 Transtheoretical Model of Behavior Change (TTM) ................................ 41 6.2.1 Usefullness of the TTM ..................................................................... 46 6.2.2 Limitations of the TTM ...................................................................... 48 6.2.3 Conclusion ........................................................................................ 51 6.3 Social Cognitive Theory (SCT) ................................................................ 52 6.3.1 Usefullness of the SCT ..................................................................... 57 3 6.3.2 Limitations of the SCT ...................................................................... 58 6.3.3 Conclusion ........................................................................................ 59 6.4 Behavioral Economics ............................................................................. 60 6.4.1 Usefulness of BE .............................................................................. 62 6.4.1.1 Social / Peer Feedback .............................................................. 62 6.4.1.2 Incentives ................................................................................... 63 6.4.1.3 Framing and Defaults ................................................................. 68 6.4.2 Limitations of BE ............................................................................... 72 6.4.3 Conclusion ........................................................................................ 76 6.5 Fogg Behavior Model and Tiny Habits .................................................... 77 6.5.1 Usefullness of FBM and Tiny Habits ................................................. 80 6.5.2 Limitations of FBM and Tiny Habits .................................................. 83 6.5.3 Conclusion ........................................................................................ 85 6.6 Self Determination Theory ....................................................................... 86 6.6.1 Usefulness of SDT ............................................................................ 89 6.6.2 Limitations of SDT ............................................................................ 91 6.6.3 Conclusion ........................................................................................ 92 7 Synopsis of theories ...................................................................................... 94 7.1 Overlapping constructs across theories .................................................. 94 7.1.1 Definitions of constructs across HBCTS ........................................... 94 7.1.2 Overlapping constructs across HBCTs in table form ........................ 97 7.1.3 Overlapping constructs across HBCTs in graphical form .................. 98 7.2 Uniqueness of HBCTs ........................................................................... 101 7.3 A comparison of HBCTs by consistency of operationalization and strength of research ...................................................................................................... 105 7.3.1 Degree of operationalization ........................................................... 105 7.3.2 Strength of Research / Research Quality ....................................... 106 4 8 Discussion ................................................................................................... 107 8.1 Similarities and Differences ................................................................... 107 8.2 New vs. established Theories ............................................................... 107 8.3 Considerations for further research ....................................................... 108 8.4 A Meta Theory of Health Behavior Change ........................................... 109 8.5 Limitations ............................................................................................. 110 9 Conclusion ................................................................................................... 114 10 Literature ...................................................................................................... 116 11 Abstract (english) ......................................................................................... 139 12 Abstract (german) ........................................................................................ 140 13 Appendix ...................................................................................................... 141 13.1 Acknowledgements ............................................................................ 141 13.2 Curriculum Vitae (CV) ........................................................................ 142 13.3 Declaration of Authorship (Eidesstattliche Erklärung) ........................ 142 13.4 List of abbreviations ........................................................................... 143 13.5 List of Figures and Tables .................................................................. 144 13.5.1 List of Figures ................................................................................. 144 13.5.2 List of Tables .................................................................................. 146 5 2 Working Hypothesis and Guiding Questions Non-communicable and chronic diseases such as diabetes and cardiovascular diseases are on the rise worldwide. Lifestyle behaviors such as physical activity, nutrition and sleep are a critical modifiable factor to prevent and treat such diseases. To this end effective health behavior change interventions are needed, which often suffer from high dropout rates and low rates of long term change. Few interventions to change health behavior are sustainable, especially in the long term. Health behavior change theories (HBCTs) that allow to explain and predict health behavior could improve these rates. Improving these theories could help increase health behavior change rates. They could offer more efficient and reliable methods of changing health behavior. In this thesis we analyze and compare selected HBCTs against each other. The leading questions of this doctoral thesis are: Which are the most often used and researched theories of HBC? Which limitations do they have? Which newer theories could complement the traditional theories? Are newer theories and models developed more successful in changing and explaining health behavior than more established theories and models? Do more established theories and models miss important aspects of Health Behavior Change? Current applications and limitations of theories are presented and discussed. Uniqueness and commonalities are contrasted and the evidence base described. We also propose and explain future directions for further research. 6 3 Introduction The