ACTIVE INGREDIENTS
5.2 IMPORTANCE OF THE INTERVENTION THEORY
5.2 Importance of the Intervention Theory
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Information on the required material resources is necessary to ensure their availability in appropriate quantity and quality for use in interven- tion delivery.•
Information on the required human resources is essential to negotiate the personnel or staff complement to hire and to devise staff recruitment strategies. Awareness of the personal and professional profile helps in delin- eating the focus of the job interview; in selecting the most qualified; and in planning the staff training (see Chapter 8).•
The description of the intervention gives directions for developing the intervention protocol for standardized interventions; delineating the algorithm for tailored and adaptive interventions; and generating the modules for providing technology (web, computer, or mobile)-based interventions. The detailed description of the intervention components, and in particular the treatment recommendations, assists in creating written documents that clients may refer to in carrying out the treatment recommendations properly.2. The implementation or actual delivery of the intervention.
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The specification of the health problem and its aspects addressed by the intervention is critical for identifying the timing within the trajectory of the health problem experience, for providing the intervention. This has impli- cations for recruiting clients and delivering the intervention at the most opportune time, so that clients receive the intervention when it is most needed and benefit from it.•
The description of the intervention’s components, mode of delivery and dose, as well as the sequence in which the components are to be given, informs:a. The development of the treatment protocol or manual that details the content, activities, and treatment recommendations to be covered in the intervention sessions or modules, and the sequence for providing them within and across sessions or modules (see Chapter 7). Health profes- sionals are expected to follow the manual in delivering the intervention in order to minimize variation and enhance fidelity of delivery. Fidelity is associated with increased effectiveness of the intervention.
b. The generation of instruments to monitor and assess fidelity with which health professionals deliver the intervention. Results of this assessment are used to provide feedback and support to health professionals.
c. The creation of measures to assess the extent to which clients apply the treatment recommendations. Results of this assessment determine the need for discussing issues of adherence to treatment during the inter- vention delivery period.
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Awareness of client and contextual factors that influence implementation of the intervention assists in identifying elements of the intervention that are to be modified, and how. The modifications are necessary for consis- tency with the characteristics and life circumstances of subgroups of the client population and to fit with the features of the local context in which the intervention is delivered, without jeopardizing fidelity.3. The design and conduct of a study to evaluate the intervention’s effectiveness.
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The conceptual definition of the health problem and its aspects addressed by the intervention is important for identifying the target client population, specifying the inclusion criteria, and selecting the instrument for measuring the problem experience.•
Understanding of the client factors that affect the experience of the health problem as well as the intervention’s implementation and/or effectiveness guides the specification of: (1) additional exclusion criteria whereby clients with particular characteristics that interfere with their ability to comprehend and apply the treatment recommendations are excluded; and (2) factors that moderate the effectiveness of the intervention; these factors should be assessed and modeled appropriately (e.g. covariate, subgroup analysis) in the data analysis aimed at determining the effects of the intervention.•
Knowledge of the characteristics and life circumstances (e.g. locations or events frequently attended by potentially eligible clients) of the target client population helps in selecting or devising recruitment strategies to reach all subgroups of the client population (see Chapter 15).•
Awareness of contextual factors potentially influencing the delivery and effectiveness of the intervention provides guidance for assessing them (quantitatively or qualitatively) and exploring how they contribute (hinder or enable) to the provision and effects of the intervention.•
Understanding of the intervention’s active ingredients is important for selecting and specifying the comparison treatment. The latter treatment should not incorporate components operationalizing the active ingredients of the intervention (see Chapter 15).•
The instruments for assessing the fidelity of intervention delivery by health professionals and treatment adherence by clients are administered at the most appropriate time. The respective data are analyzed to determine the association between level of intervention implementation and improve- ment in outcomes. This association assists in interpreting the findings related to the effectiveness of the intervention.•
Delineation of the mechanism through which the intervention impacts the ultimate outcomes gives directions for:a. Selecting instruments that validly measure the mediators and the ulti- mate outcomes.
b. Determining the most appropriate points in time before, during, and fol- lowing delivery of the intervention, at which the mediators and the ulti- mate outcomes should be measured. The time points should coincide with those at which changes in the respective variables are expected to take place.
c. Estimating the anticipated size of the intervention effect on the ultimate outcome; this is helpful in conducting the power analysis for the evalua- tion study, in particular when the intervention is newly designed.
d. Planning and performing the data analysis. This involves: (1) specifying the hypothesized pattern of change in the mediators and ultimate out- comes, and testing it empirically; (2) specifying the inter-relationships among the receipt of the intervention or the level of fidelity and adher- ence, mediators, and ultimate outcomes, as well as the moderating effect of client or contextual factors, and examining these inter-relationships using advanced statistical tests.
4. The interpretation of the evaluation study’s results.
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The intervention theory proposes the direct and indirect relationships among client and contextual factors, the intervention, the mediators, and the ultimate outcomes to be examined, and provides the frame of referenceReferences
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for interpreting the results of the evaluation study. It highlights what exactly contribute to the improvement or non-improvement in the ulti- mate outcomes.
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Results of a theory-informed evaluation study provide answers to the clini- cally or practice relevant questions (Chapter 1) of: Who would most benefit from the intervention, given in what mode and at what dose, in what con- text? And how does the intervention work in producing beneficial ultimate outcomes related to improvement in the health problem experience, reduction in its consequences, and enhanced well-being.REFERENCES
Anderson, L.M., Petticrew, M., Rehfuess, E., et al. (2011) Using logic models to capture complexity in systematic reviews. Research Synthesis Methods, 2(1), 33–42.
Ball, L., Ball, D., Leveritt, M., et al. (2017) Using logic models to enhance the methodo- logical quality of primary health-care interventions: Guidance from an intervention to promote nutrition care by general practitioners and practice nurses. Australian Journal of Primary Health, 23, 53-60.
Bartholomew, L.K., Kok, G., & Markham, C.M. (2016) Planning Health Promotion Programs: An Intervention Mapping Approach (4th ed). John Wiley and Amp; Sons Inc, New York.
Baxter, S.K., Blank, L., Woods, H.B., et al. (2014) Using logic model methods in systematic review synthesis: Describing complex pathways in referral management interven- tions. BMC Medical Research Methodology, 14, Article Number 62.
Bonell, C., Jamal, F., Melendez-Torres, G. J., & Cummins, S. (2015) “Dark logic”:
Theorising the harmful consequences of public health interventions. Journal of Epidemiology and Community Health, 69, 95-98.
Brousselle, A. & Champagne F. (2011) Program theory evaluation: Logic analysis.
Evaluation and Program Planning, 34(1), 69–78.
Chen, H.-T., Pan, H.-L.W., Morosanu, L., & Turner, N. (2018) Using logic models and the action model/change model schema in planning the learning community program: A comparative case study. The Canadian Journal of Program Evaluation, 33(1), 49–68.
Dalkin, S.M., Greenhalgh, J., Jones, D., et al. (2015) What’s in a mechanism? Development of a key concept in realist evaluation. Implementation Science, 10, 49–55.
Davidoff, F., Dixon-Woods, M., Leviton, L., & Michie, S. (2015) Demystifying theory and its use in improvement. BMJ Quality and Safety, 24(3), 228–238.
De Souza, D.E. (2013) Elaborating the context-mechanism-outcome configura- tion (CMOc) in realist evaluation: A critical realist perspective. Evaluation, 19(2), 141–145.
Greenhalgh, T., Wong, G., Jagosh, J., et al. (2015) Protocol—The RAMESES II study:
Developing guidance and reporting standards for realist evaluation. BMJ Open, 5, e008567.
Medical Research Council (2019) Developing and Evaluating Complex Inter
ventions. Authors
Pawson, R. & Manzano-Santaella, A., (2012) A realist diagnostic workshop. Evaluation, 18(2), 176–191.
Sidani, S. & Sechrest, L. (1999) Putting theory into operation. American Journal of Evaluation, 20(2), 227–238.
Slater, K.L. & Kothari, A., (2014) Using realist evaluation to open the back box on knowl- edge translation: A State-of-the-art review. Implementation Science, 9,115–128.
US General Accountability Office (2012) Designing Evaluations. GAO-12-208G.
Washington, DC: The Auhor
Wong, G., Greenhalgh, T., Westhorp, G., & Pawson, R. (2012) Realist methods in medical education research: What are they & what can they contribute? Medical Education, 46, 89-96.