Applying the theory of planned behaviour to multiple sclerosis patients’ decisions on disease modifying therapy – questionnaire concept and validation

BackgroundPatients making important medical decisions need to evaluate complex information in the light of their own beliefs, attitudes and priorities. The process can be considered in terms of the theory of planned behaviour.Decision support technologies aim at helping patients making informed treatment choices. Instruments assessing informed choices need to include risk knowledge, attitude (towards therapy) and actual uptake. However, mechanisms by which decision support achieves its goals are poorly understood.Our aim was therefore to develop and validate an instrument modeling the process of multiple sclerosis (MS) patients’ decision making about whether to undergo disease modifying (immuno-)therapies (DMT).MethodsWe constructed a 30-item patient administered questionnaire to access the elaboration of decisions about DMT in MS according to the theory of planned behaviour. MS-patients’ belief composites regarding immunotherapy were classified according to the domains “attitude”, “subjective social norm” and “control beliefs” and within each domain to either “expectations” or “values” yielding 6 sub-domains. A randomized controlled trial (n = 192) evaluating an evidence based educational intervention tested the instrument’s predictive power regarding intention to use immunotherapy and its sensitivity to the intervention.ResultsThe psychometric properties of the questionnaire were satisfactory (mean item difficulty 62, mean SD 0.9, range 0–3). Responses explain up to 68% of the variability in the intention to use DMT was explained by up to 68% in the total sample. Four weeks after an educational intervention, predictive power was higher in the intervention (IG) compared to the control group (CG) (intention estimate: CG 56% / IG 69%, p = .179; three domains CG 56% / IG 74%, p = .047; six sub-domains CG 64% / IG 78%, p = .073). The IG held more critical beliefs towards immunotherapy (p = .002) and were less willing to comply with social norm (p = .012).ConclusionsThe questionnaire seems to provide a valid way of explaining patients’ inherent decision processes and to be sensitive towards varying levels of elaboration. Similar tools based on the theory of planned behaviour could be applied to other decision making scenarios.

[1]  W. L. Benedict,et al.  Multiple Sclerosis , 2007, Journal - Michigan State Medical Society.

[2]  M. Conner,et al.  Efficacy of the Theory of Planned Behaviour: a meta-analytic review. , 2001, The British journal of social psychology.

[3]  Glyn Elwyn,et al.  Shared decision-making in health care: Achieving evidence-based patient choice (Paperback) , 2009 .

[4]  G. Kok,et al.  The Theory of Planned Behavior: A Review of its Applications to Health-Related Behaviors , 1996, American journal of health promotion : AJHP.

[5]  C. Heesen,et al.  Informed shared decision making about immunotherapy for patients with multiple sclerosis (ISDIMS): a randomized controlled trial , 2008, European journal of neurology.

[6]  A. Giordano,et al.  Decisions on multiple sclerosis immunotherapy: New treatment complexities urge patient engagement , 2011, Journal of the Neurological Sciences.

[7]  France Légaré,et al.  Turning signals into meaning –‘Shared decision making’ meets communication theory , 2012, Health expectations : an international journal of public participation in health care and health policy.

[8]  N. Donner-Banzhoff,et al.  Partizipative Entscheidungsfindung in der Gesundheitsversorgung , 2008 .

[9]  G. Elwyn,et al.  Adjuncts or adversaries to shared decision-making? Applying the Integrative Model of behavior to the role and design of decision support interventions in healthcare interactions , 2009, Implementation science : IS.

[10]  Martin Härter,et al.  Participation preferences of patients with acute and chronic conditions , 2007, Health expectations : an international journal of public participation in health care and health policy.

[11]  M. Hayward,et al.  How well are we doing? , 2004, Mental health today.

[12]  G. Elwyn,et al.  Where is the theory? Evaluating the theoretical frameworks described in decision support technologies. , 2008, Patient education and counseling.

[13]  France Légaré,et al.  Risk communication in practice: the contribution of decision aids , 2003, BMJ : British Medical Journal.

[14]  M Nübling,et al.  Patient education program to enhance decision autonomy in multiple sclerosis relapse management: a randomized-controlled trial , 2009, Multiple sclerosis.

[15]  Tanya M. Swart,et al.  A review of health behaviour theories: how useful are these for developing interventions to promote long-term medication adherence for TB and HIV/AIDS? , 2007, BMC public health.

[16]  Jürgen Kasper,et al.  Decisional role preferences, risk knowledge and information interests in patients with multiple sclerosis , 2004, Multiple sclerosis.

[17]  S. Michie,et al.  Using the theory of planned behaviour to predict screening uptake in two contexts , 2004 .

[18]  Marie Johnston,et al.  Application of the Theory of Planned Behaviour in Behaviour Change Interventions: A Systematic Review , 2002 .

[19]  R. Thomson,et al.  Decision aids for people facing health treatment or screening decisions. , 2003, The Cochrane database of systematic reviews.

[20]  Richard Cooke,et al.  How well do the theory of reasoned action and theory of planned behaviour predict intentions and attendance at screening programmes? A meta-analysis , 2008, Psychology & health.

[21]  I. Ajzen,et al.  Belief, Attitude, Intention, and Behavior: An Introduction to Theory and Research , 1977 .

[22]  Andreas Sönnichsen,et al.  The theory of planned behaviour in a randomized trial of a decision aid on cardiovascular risk prevention. , 2010, Patient education and counseling.

[23]  S. Sutton.  Predicting and Explaining Intentions and Behavior: How Well Are We Doing? , 1998 .

[24]  V. Entwistle,et al.  Assessing patients' participation and quality of decision-making: insights from a study of routine practice in diverse settings. , 2004, Patient education and counseling.

[25]  T. Marteau,et al.  A measure of informed choice , 2001, Health expectations : an international journal of public participation in health care and health policy.

[26]  C. Abraham,et al.  Making psychological theory useful for implementing evidence based practice: a consensus approach , 2005, Quality and Safety in Health Care.

[27]  Franziska Marquart,et al.  Communication and persuasion : central and peripheral routes to attitude change , 1988 .

[28]  Jörg Dirmaier,et al.  Measurement of shared decision making - a review of instruments. , 2011, Zeitschrift fur Evidenz, Fortbildung und Qualitat im Gesundheitswesen.

[29]  A. Barratt,et al.  Evidence Based Medicine and Shared Decision Making: the challenge of getting both evidence and preferences into health care. , 2008, Patient education and counseling.

[30]  Heidemarie Keller,et al.  Absolute Cardiovascular Disease Risk and Shared Decision Making in Primary Care: A Randomized Controlled Trial , 2008, The Annals of Family Medicine.

[31]  I. Ajzen.  Nature and operation of attitudes. , 2001, Annual review of psychology.

[32]  Icek Ajzen,et al.  From Intentions to Actions: A Theory of Planned Behavior , 1985 .

[33]  Glyn Elwyn,et al.  Understanding surgery choices for breast cancer: how might the Theory of Planned Behaviour and the Common Sense Model contribute to decision support interventions? , 2011, Health expectations : an international journal of public participation in health care and health policy.

[34]  H. Bekker,et al.  The loss of reason in patient decision aid research: do checklists damage the quality of informed choice interventions? , 2010, Patient education and counseling.

[35]  J. Beckmann,et al.  Action control : from cognition to behavior , 1985 .

[36]  I. Ajzen.  Constructing a TpB Questionnaire: Conceptual and Methodological Considerations , 2002 .