The "state-of-the-art" adherence interventions target the patient, the provider, and the health care system. Several programmes have demonstrated good results using multilevel team approaches (85 - 87). Adequate evidence exists to support the utility of innovative, modified health care system teams in addressing the problem (25,88).
However, research on interventions to promote adherence has focused largely on modifying patient behaviour. According to several published reviews on adherence, no single intervention targeting patient behaviour is effective, and the most promising methods of improving adherence behaviour use a combination of the strategies listed below (89 - 91):
- patient education (92);
- behavioural skills (93,94);
- self-rewards (95);
- social support (96); and
- telephone follow-up (97).
Various combinations of these techniques have been shown to increase adherence and improve treatment outcomes. However, even the most efficacious patient-focused interventions have no substantial effects on adherence behaviour over the long term (43) and few randomized controlled trials targeting patient adherence behaviour have been reported (91).
A. Patient interventions
The most effective adherence-enhancing interventions directed at patients aim to enhance self-regulation or self-management capabilities. Self-management programmes offered to patients with chronic diseases can improve health status and reduce health care utilization and costs. Some data suggest a cost-to-savings ratio of 1: 10 (98). Such approaches are grounded in basic principles of learning (99,100). This is critical in the management of patients with chronic illness, as over the long term patients must rely on unassisted effort and self-regulation to maintain their behaviour. Several strategies appear to be effective, at least in the short term. These include:
- stimulus control;
- behavioural rehearsal;
- corrective feedback;
- behavioural contracting;
- commitment enhancement;
- creating social support;
- reinforcement; and
- relapse prevention.
Since the early 1980s there has been sufficient evidence to support the use of these strategies. These are most effective when used as components of multi-modal programmes and implemented in an individualized tailored manner, including creating social support, reorganization of the service-delivery environment, increasing accessibility of services, and a collaborative treatment relationship.
A meta-analysis of 28 studies revealed that the key intervention components were providing reinforcement for patients' efforts to change, providing feedback on progress, tailoring education to patients' needs and circumstances, teaching skills and providing access to resources, and continuity of care (proactive) (101). An earlier review, Garrity & Garrity (102) identified four intervention themes associated with successful outcomes: active patient theme (promote self-care), social support theme (help in meeting illness-related demands), fear arousal theme (increase concern about the consequences of the disease), and patient instruction theme. The self-care (contingency contracting element) and social support themes were associated with the strongest effects on treatment outcome.
There has been little research on the most effective methods for improving adherence to recommended treatment in children. Education alone does not promote the desired patient outcomes and the format of the educational programme may be less important than the actual presentation and understanding of the information (103). However, when behavioural strategies were used in conjunction with patient education, adherence to recommended treatment improved by an average of 25% (104).Multicomponent behavioural strategies that have been found to be successful in promoting adherence include self-monitoring, contingency contracting, reinforcing, tailoring and cueing. In addition, individual rather than group educational sessions can be better adapted to the specific needs of a child and his or her family, and are therefore anticipated to have a greater impact on outcomes (105). There is a need for research to identify and test developmentally-appropriate interventions to remedy the problem of paediatric nonadherence and improve health care outcomes for children.
The need for research to further our understanding of the differences in adherence behaviour at different stages of development has been only partially met. While some progress has been made in understanding and modifying adherence among paediatric populations there remains much to be learned. The research to date has suffered from a lack of methodological rigour and attention to theoretically-based investigations, particularly the utilization of developmentally-based theory to guide adherence interventions. Children are not small adults; children and adolescents have specific needs that differ from those of their adult counterparts. Advances in the area of adherence will be dependent upon:
- designing and testing tools for objectively measuring adherence that are non-intrusive (e.g. electronic monitoring), and that children and adolescents are willing and able to use;
- addressing psychosocial and family factors that modify adherence in children and adolescents;
- designing and testing age- and disease-specific quality-of-life scales for children and adolescents; and
- designing and testing educational and behavioural strategies appropriate for children and adolescents.
The desired outcome is for practitioners to tailor scientifically-based adherence interventions to the developmental stage of the patient. As interdisciplinary expertise is brought to bear on developing scientifically- based policy for addressing the developmental aspects of adherence and managing care, the gaps in the understanding of nonadherence should begin to close.
B. Interventions directed to providers
Because providers have such a significant role in adherence, designing interventions to influence their behaviour seems a reasonable strategy. However, few investigations on this subject have been reported in the literature. Training providers in patient-centred methods of care may be effective, but the strongest effects of such training appear to be on patient satisfaction with treatment. Some recent studies suggest that adherence interventions based on behavioural principles can be successfully implemented by social workers and nurses (106,107). Studies of physicians trained to use goal-setting, feedback and ongoing education reveal better patient outcomes, though such studies have seldom measured adherence as an outcome.
C. Health system
Interventions in the health system are higher order interventions affecting health policy; organization and financing of care and quality of care programmes. One example is the creation and adoption of chronic care models of service delivery, which, at least in patients with diabetes and asthma, have been shown to result in better patient outcomes. However the extent to which these models are related to adherence is not yet clear.