NUR 699: why use a change theory or EBP model?

Read the first sentence carefully, because it contains two different objects and the post that conflates them cannot answer the third question. "A theory or model related to change" and "an EBP model" are not synonyms. Lewin's unfreeze-change-refreeze, Rogers' diffusion of innovations and Kotter's eight steps are change theories, borrowed from psychology, sociology and organisational studies. The Iowa Model, the Johns Hopkins model, Stetler and the ACE Star Model are evidence-based practice process models, built to take a clinical question from trigger to sustained practice. They do different jobs, they answer different questions, and a post that lists them together as "models of change" has flattened the distinction the assignment is testing. The third question compounds it, because it asks which model is most appropriate for your intervention — and appropriateness is only assessable once you have said what kind of thing the model is supposed to be doing.

The tidiest way to hold them apart is Per Nilsen's taxonomy, which sorts everything used in implementation science into five categories with three overarching aims: describing or guiding the process of translating research into practice, understanding or explaining what influences implementation outcomes, and evaluating implementation. That structure is worth learning for this post specifically, because it converts the question "which model should I use?" from a matter of preference into a matter of fit. You choose the category first by asking what your problem actually is, and only then choose an approach inside it. Picking a favourite model and retrofitting a rationale is the failure the third question is designed to expose. Nilsen's paper exists precisely because the field had accumulated approaches faster than it had accumulated ways to tell them apart, which is the same problem a student faces when four models all look reasonable.

Sorted that way, the options stop competing with each other:

Now the first question, which is easy to answer badly because the honest reason is not the obvious one. The weak answer is that a theory lends structure and credibility. The real reason is that a model makes your assumptions explicit and testable before you commit resources. A determinant framework forces you to write down what you think will get in the way, which means you find out in week two rather than month five. A process model stops you skipping the pilot, which is the step under most schedule pressure and the one whose absence is most expensive. An evaluation framework forces you to define success while you can still design a measure for it. Structure is a by-product; the value is in being wrong early and cheaply. That reframes the answer towards the project: the model is not there to show you read the literature, but to stop you spending a semester learning what an afternoon could have predicted.

The second question deserves a real answer rather than a reflex, because it explicitly invites you to weigh benefit against effort — and there is a defensible "often not". The value of a model is almost entirely prospective. Chosen before design, it shapes what you do. Applied afterwards to satisfy a rubric, it is a documentation exercise that costs hours and changes nothing about the intervention, because every decision it might have informed has already been made. This is visible in the published literature, not just in student projects: a 2025 scoping review of EBP implementation in nursing found reporting that focused more on expected outcomes than on the strategies actually used months or years earlier, and only three of twenty-six studies explicitly used Proctor's outcome taxonomy. The distinction worth drawing is between a model that shaped decisions and a model that described them afterwards, and only the first can be said to have earned its cost.

So say when it is worth it and when it is not, and you have answered the question as asked rather than defending a position nobody attacked. Worth it: where the setting is unfamiliar, where adoption depends on people you do not manage, where the change touches more than one discipline, or where you will have to defend the result to a committee. Not worth it: where the model is selected after the intervention is designed, where it is a single-unit change with a willing team, or where the chosen framework is so large that populating its domains becomes the project. The mark of a serious answer here is naming a condition under which you would not use one. Naming a boundary is also what makes the rest of your post credible, because an argument that a tool is always worth using is indistinguishable from an argument that you have never had to weigh it.

The third question says your intervention, so it is not a book review. Name the model, name your project, and then do the thing that demonstrates fit: identify the specific feature of your intervention that made you choose that category. "I chose i-PARIHS because my barrier is not the evidence but the facilitation — the protocol is not disputed and it is still not being followed" is an argument. "I chose the Iowa Model because it is widely used in nursing and provides a systematic approach" is a description that would be equally true of somebody else's project, which is the test it fails. Do the same for the cost question: say what your project would have looked like without the model, and if the answer is 'the same', that is worth knowing before you write the rest of the proposal rather than after.