Models of motivation and a motivational model of pain self-management
Theories of motivation attempt to explain the initiation, direction, persistence, intensity, and termination of a particular behaviour (Landy and Becker 1987). Motivation can thus be viewed as a process that involves all of the factors that influence behaviour. Most theories and models of human behaviour, including a motivational model we are developing for understanding pain self-management, assume that behavioural change is influenced primarily by two factors: (1) the perceived importance of behaviour change and (2) the patient’s belief that behaviour change is possible (i.e. self-efficacy) (Jensen et al. 2003). In fact, because of the high degree of overlap among the models, as well as the fact that it is often possible to explain changes in motivation or behaviour from the viewpoint of any one of the models, finding unequivocal support for one model over the others is quite difficult (Weinstein 1993).
On the other hand, the existence of significant areas of overlap among motivational models may be used to form a foundation for a general model of motivation for pain self-management.
Fig. 24.1 Motivational model of pain self-management. Reprinted from The Journal of Pain, 4(9), Mark P. Jensen, Warren R. Nielson, and Robert D. Kerns. Toward the development of a motivational model of pain self-management, pp. 477-92, Copyright (2003), with permission from Elsevier.
An initial version of such a model, the Motivational Model for Pain Self-Management, is presented in Figure 24.1. The primary outcome variable in this model is pain self-management coping behaviour, which may be defined by a set of behaviours and cognitions that are thought to reflect ‘adaptive’ pain management, and by avoidance of behaviours or cognitions that are thought to reflect ‘maladaptive’ pain management. The specific self-management coping behaviours listed in Figure 24.1 were drawn from the coping responses that clinicians and researchers have most closely associated with improved function and with positive outcomes in pain treatment (Jensen et al. 1994; Loeser and Turk 2001; Nielson et al. 2001), but the list is by no means exhaustive.
Self-management behaviour that is adaptive for one condition may, however, be ineffective or even harmful for another condition. For example, while patients with low back pain may benefit from maintaining a programme of regular aerobic exercise, the same exercises might cause further joint damage in patients with knee or hip arthritis. As more is learned about the relative importance of specific coping behaviours and cognitions and about the conditions under which these are adaptive, maladaptive, or neutral, the operational definition of pain self-management listed in Figure 24.1 should be updated.
The concept of readiness to self-manage pain (Prochaska and DiClemente 1984a; Kerns et al. 1997) is central to the Motivational Model for Pain Self-Management because it defines motivation. The model hypothesizes that patients will engage in specific pain self-management strategies dependent on their readiness, or motivation, to use these strategies. In the model, motivation is influenced by the two primary variables already mentioned, i.e. beliefs about the importance of engaging versus not engaging in pain self-management behaviours (‘outcome expectancies’, ‘value’, ‘importance’), and beliefs about one’s ability to engage in pain self-management behaviours (‘self-efficacy’, ‘confidence’). Perceived importance is influenced by the value of expected outcomes, such as pain reduction, increased strength and activity tolerance, increased cognitive abilities, versus the perceived costs of pain self-management. The outcome expectancies are in turn affected by the patient’s learning history, since a history of reinforcers or punishers for certain pain self-management behaviours will respectively increase or decrease the value placed on pain self-management.
Similarly, a number of factors can contribute to a patient’s confidence in his or her ability to engage in a specific behavioural response. These include a history of successfully engaging in that response while undergoing treatments that elicit new behavioural responses to pain (Fordyce 1976; Fordyce et al. 1968), modelling of behaviour by others (Bandura 1986), effective persuasion (Miller and Rollnick 2002), and the removal of perceived barriers.
Although the Motivational Model for Pain Self-Management may appear static, with its final endpoint determined by the effects of perceived importance and self-efficacy on readiness to self- manage pain, we view the model as dynamic because of the many factors described above that influence motivation. The model provides what we hope is a frame of reference for understanding patient motivation for self-management, and, more importantly, for identifying ways to improve this motivation.
Moreover, preliminary evidence supports hypotheses based on this model. Molton and colleagues (Molton et al. 2008) obtained survey data from 130 adults with spinal cord injury (SCI) and chronic pain, that included: (1) measures of average pain intensity during the past week; (2) readiness to self-manage pain (assessed using the Multidimensional Pain Readiness to Change Questionnaire, see Nielson et al. 2003, and discussion of motivational measures in the next section); (3) and ratings of perceived importance, self-efficacy, and frequency of use of both (a) regular exercise and (b) task persistence as pain management strategies. Task persistence was used by too many of the sample to be able to test the mediation hypotheses of the Motivational Model of Pain Self-Management; however, the distribution of the amount of exercise reported by the sample had enough variance to test the model’s hypotheses. Molton et al.’s findings supported the model. Specifically, patient self-efficacy for exercise, perceived importance of exercise, and motivation (readiness) were all significantly associated with reported exercise frequency. As predicted, they also found that the effects of self-efficacy and perceived importance were mediated by motivation. Thus, patient readiness to make changes in (or maintain) exercise behaviour is influenced by their perception of the importance of exercise and their perception of their own ability to exercise. In turn, patient readiness to exercise is a strong predictor of exercise behaviour.