Nursing and Health Interventions. Souraya Sidani

outcomes (Renzoto et al., 2013). At the healthcare organization and system level, client‐centered care contributed to the development of new and improved services (Mockford et al., 2012).

      The provision of client‐centered care, the cornerstone of high‐quality healthcare (Van Belle et al., 2019), requires the availability of interventions with demonstrated appropriateness, acceptability, effectiveness, safety, and efficiency. Appropriate interventions are logical, reasonable, and sound treatments that address a specific health problem. This implies that the nature of the interventions, reflected in its active ingredients, is consistent with the nature of the health problem.

Acceptable interventions are desirable by clients expected to receive the interventions. Desirable interventions are perceived as consistent with the clients' beliefs about the health problem and its treatment, suitable to their lifestyle, safe and convenient to apply in their daily life (Sidani et al., 2018). Related to acceptability is the notion of cultural relevance of interventions; it refers to the congruence of the interventions' components, mode and dose of delivery, with the beliefs, values, and norms held by particular groups or ethno‐cultural communities (Barrera et al., 2013). Effective interventions produce the best health outcomes by activating the anticipated mechanism of action (Dalkin et al., 2015); that is, they induce changes in clients' cognition, skills, or behaviors that mediate improvements in the experience of the health problem, health, and well‐being. Safe interventions are associated with no or minimal risks or discomfort (Bonell et al., 2015). Efficient interventions are optimized in terms of content, delivery, and resources required for their implementation, to maximize health outcomes; that is, they yield the highest impact (i.e. large improvement in the outcomes in a large proportion of the population) within a reasonably short time period (i.e. speed of recovery) (Benedikt et al., 2016; Morin et al., 2014).

      New approaches are needed to design and evaluate health interventions in ways that inform the application of client‐centeredness in practice. Approaches for designing (1) appropriate health interventions rely on generating a comprehensive understanding of the health problem (see Chapter 3) and identification of the intervention's active ingredients (see Chapter 4), which are integrated into the intervention theory (see Chapter 5); (2) acceptable interventions involve the engagement of clients in the design of interventions, the development of tailored or adaptive interventions (see Chapter 4), and the assessment of clients' perceived acceptability of interventions (see Chapter 11). Approaches for evaluating the effectiveness, safety, and efficiency of health interventions entail the recognition of the complexity of the real world (see Section 1.4) and use of a range of research designs and methods to find answers to the practice‐related questions listed in Section 1.2. The goal of intervention research is to generate evidence that is grounded in and useful to practice (Westfall et al., 2009), which is characterized as client‐centered.

1.4 COMPLEXITY OF THE REAL WORLD

      The complexity of the real world is a fact. Clients live in a complex environment where multiple factors contribute to their health and their capacity to promote healthy living. They may experience one or more health problems associated with a range of determinants. These complex health problems require complex interventions for successful remediation. Several health professionals are involved in the delivery of complex intervention, in a context that is characterized by factors, operating at different levels and contributing to the success (or failure) of the intervention implementation and effectiveness. The complexity of the real world should be accounted for, and not ignored as is the case in the RCT design, when developing and evaluating health interventions in order to generate evidence of relevance to practice.

      Accounting for complexity demands acknowledgement of multi‐causality in the design and evaluation of health interventions, as well as of the individuality of clients. This can be achieved with the development of theory of the health problem (see Chapter 3), multicomponent interventions (see Chapter 4), theory of change (see Chapter 4 and 5), as well as examining the influence of contextual factors on the implementation of the intervention (see Chapter 13) and individual variability in clients' responses to interventions.

      1.4.1 Theory of the Health Problem

In practice, many clients present with one or more health problems and a range of life circumstances (or context). The experience of each problem may be associated with multiple determinants or causes, occurring in different domains of health (e.g. physical, psychological) and at different levels (e.g. intrapersonal, interpersonal, environmental) (Diez‐Roux, 2011). The problems and their determinants are often inter‐related, forming a “web of causation” (Golfam et al., 2015), also called multi‐causality. Understanding these inter‐relations is essential for designing and evaluating health interventions; this can be achieved with the development of the theory of the health problem to be targeted by an intervention. The theory of the health problem is a means for integrating the determinants of the health problem and delineating the complex inter‐relationships among them (Fleury & Sidani, 2018). The theory of the health problem points to aspects of the problem amenable to change, which informs the design of interventions. Interventions based on a clear understanding of the health problem were found to be most successful (e.g. Glanz & Bishop, 2010; Prestwich et al., 2014). The theory is also useful in guiding practice; it delineates aspects of the health problem that should be assessed, thereby ensuring a comprehensive and thorough assessment and understanding of the clients' condition, as advocated in client‐centered care.

      1.4.2 Development of Multicomponent Interventions

      Complex health problems require complex solutions. Complex interventions consist of multiple components (Medical Research Council, 2019). Each component involves a set of inter‐related activities, performed by clients and health professionals that have the common goal of managing a particular aspect (e.g. one determinant) of the health problem (Greenwood‐Lee et al., 2016). Complex interventions can be delivered in a standardized way whereby all clients are given all components, or tailored to the individual clients' experience of the health problem. In the latter case, clients are provided one component or a subset of components that is or are most appropriate to address the most salient aspect of the health problem as clients experience it.

      1.4.3 Development of the Theory of Change

      Each component of a complex health intervention targets a particular aspect of the health problem, and, therefore, activates a unique mechanism of action. When a combination of components is delivered, the components may act interdependently in producing complex, multiple causal pathways that represent the mechanism of action responsible for the intervention's effects on the outcomes. The theory of change integrates these pathways (Mayne, 2015; Montague, 2019; Powell, 2019) to explain how the complex intervention, in its totality, works to bring about beneficial changes in the health problem and other outcomes (Bleijenberg et al., 2018).

      The theory of change guides the plan and conduct of intervention evaluation studies. It identifies the interventions' processes, mediators, and outcomes to be investigated; gives direction for their measurement as well as the timing of their assessment; and assists in interpreting the findings. In practice, health professionals' awareness of the theory empowers engagement in an enlightened