Nursing and Health Interventions. Souraya Sidani

be used to generate the theory of the problem.

      The information gained from this analysis assists in formulating the theory or logic model of the health problem. Specifically, the initial definition of the problem is refined as needed. A comprehensive list of determinants is generated and their direct and indirect relationships with the problem are delineated and explained, and where available, supported by empirical evidence.

      3.3.1.3 Strengths

The theoretical approach to generate an understanding of the health problem is advantageous. Theories provide a generalizable conceptualization of the problem and its determinants (Foy et al., 2007). By transcending individual cases, middle range theories describe clearly the nature of the problem and identify its determinants or “root causes” (Davidoff et al., 2015). They provide explicit, logical explanations of why and how the determinants affect the problem directly or indirectly. Thus, theories prevent the danger of (1) mislabeling and vaguely defining health problems, (2) missing or omitting important determinants; and (3) misinterpreting associations (specifically bivariate ones that link the problem to one determinant) between the determinants and the problem, all of which have the potential to mislead the design of interventions. Middle range theories do not only explain the pathways linking the determinants to the problem, but also point to the context under which the problem is experienced and maintained, and the pathway is induced. Variations in the pathway across clients and contexts highlight the need to adapt or tailor the design of interventions. Briefly, theories are powerful tools to understand the health problem and to make informed decisions when designing interventions (e.g. Aráujo‐Soares et al., 2018; Bleijenberg et al., 2018; Medical Research Council, 2019).

      3.3.1.4 Limitations

      The theoretical approach has some limitations in gaining a comprehensive understanding of the health problem. The reliance on one single middle range theory constrains the perspective on the nature and determinants of the problem to those identified in the theory. Therefore, additional factors (in particular contextual or environmental) that may contribute to the problem could be missed; this limits the capacity to account for all possible determinants pertinent to complex problems experienced by particular client populations in particular contexts. For many health‐related problems there is a limited, if any, number of relevant middle range theories that provide an adequate understanding of the problem and all its determinants. Further, of the available middle range theories, a few have been subjected to extensive empirical test across the range of client populations and contexts, and for those tested (e.g. transtheoretical model), the results are often mixed.

      Middle range theories may have limited utility if they are not supported empirically. The theoretical approach can be complemented with the empirical approach to gain a comprehensive and accurate understanding of the health problem as actually experienced in the target client population and context.

      3.3.2 Empirical Approach

      The empirical approach relies on systematically generated evidence to gain an understanding of the health problem. The evidence is obtained through these methods: a review of pertinent literature, conduct of primary studies, and/or analysis of available data.

      3.3.2.1 Literature Review

       Overview

      Literature reviews are essential to analyze and synthesize available empirical evidence on the health problem. The literature encompasses primary quantitative and qualitative studies that investigated the problem, as well as reviews that synthesized the evidence on the experience of the problem (i.e. its indicators) and its association with determinants.

       Review of Quantitative Studies

      Quantitative studies to include in the review are the ones that aimed to describe the health problem and/or to examine its relationships, direct or indirect, with its determinants and consequences within particular client populations and settings. The studies may use different research designs.

Results of descriptive cross‐sectional studies indicate the prevalence of the problem in different client populations and clarify the nature of the problem, its indicators, and level of severity as reported by clients presenting with diverse sociodemographic, cultural, and health or clinical characteristics, at one point in time. Differences in the health problem experience across client populations or subgroups of the same target population have implications for the design of interventions, whereby different components are selected or their delivery is adapted or tailored to variations in the clients' experience of the problem.

      Results of descriptive longitudinal studies indicate changes in the experience, indicators, and severity levels of the health problem over time. Awareness of changes in the problem experience over time is informative as it guides the selection of the timing, within the health problem trajectory, for delivering the intervention; of the optimal dose at which the intervention is given which may incorporate “booster” sessions to prevent relapse; and the organization or sequence with which the intervention components are offered.

      Results of correlational cross‐sectional studies support the existence, direction, and magnitude or size of the associations between the health problem, and its determinants. They shed light on the nature of the relationships (i.e. whether direct or indirect) between the problem and determinants. Findings of correlational longitudinal studies provide evidence of the sustainability or changes in the existence, direction, or magnitude of these relationships over time; they have the potential to identify the temporal sequence linking determinants to the problem, which is required to support naturally occurring causal linkages. For example, cross‐sectional evidence has long supported the existence of a positive correlation between insomnia and depression; but it was not clear which of these two problems caused the other. Recent longitudinal evidence suggests that insomnia predicts depression and that interventions addressing insomnia could contribute to improvement in depression and not the other way as implied in cross‐sectional evidence (e.g. Fernandez‐Mendoza et al., 2015).

       Review of Qualitative Studies

      Qualitative studies to include in the review are those that focused on exploring the experience of the health problem from the clients' perspective. Clients are well known to hold implicit theories of the health problem; these theories reflect their personal construction of the problem and explanation of contributing factors (Armstrong & Dregan, 2014). Qualitative studies using different approaches (e.g. phenomenology, grounded theory) are selected if they aim to describe clients' experience of the problem (e.g. indicators, impact on daily life); elucidate factors that contributed to the problem; or generate a theory or a model summarizing and explaining the intricate relationships among the determinants and the problem. Results of qualitative studies highlight the unique way in which the health problem is experienced by particular subgroups of the client population. They also assist in clarifying the pathway linking the determinants with the problem and in providing conceptual explanations of these associations.

       Review of Reviews

Many types of literature reviews are useful in developing a comprehensive understanding of the health problem. These are well described by Snilstveit et al. (2012), Paré et al. (2015), and Hong et al. (2017). Of interest to the generation of an understanding of the health problem are reviews that synthesize theoretical or conceptual knowledge and quantitative and qualitative empirical evidence related to the problem experience and its associations with determinants.

      Theoretical or conceptual reviews are exemplified with concept analysis (Hupcey & Penrod, 2005) and framework synthesis (Carroll et al., 2013). Essentially, these consist of reviewing theoretical, empirical, and sometimes grey literature, for the purposes of: clarifying the attributes of the health problem; defining it at the theoretical and operational levels and distinguishing it from related concepts or problems;