PHLT 8048 Week 5 TPB Versus COM-B Comparison Example

Course	PHLT 8048 Research and Application of Public Health and Behavior Change Theories
Week	Week 5
Paper type	Theory comparison
Length	About 1,040 words, 6 pages
Format	APA 7 student paper
School	Walden University
Program	PhD in Public Health
Updated	October 2026

Free sample paper for PHLT 8048 Week 5

Theory Comparison: The Theory of Planned Behavior and the COM-B Model Tested Against Three Composite Night-Shift Workers Who Drive Home Drowsy, Each Theory Allowed Only the Assumptions It Already Carries

Student Name

Walden University

PHLT 8048: Research and Application of Public Health and Behavior Change Theories

Instructor Name

Month Day, Year

What this page is doingThe title sets the rule of the contest, no added assumptions, which is what makes the comparison a fair test rather than a showcase.

The Rule of the Comparison

Two theories remain in contention after the construct mapping: the theory of planned behavior and the COM-B model. This comparison builds three composite cases from the term's problem of hospital staff who drive home drowsy after night work, and asks each theory to explain all three using only constructs and assumptions it already contains. A theory that needs an addition to explain a case is not disqualified, but the addition counts against it, because a theory that grows a new piece for every case explains less than it appears to. The cases are composites drawn from patterns the author has heard from colleagues, not descriptions of real people.

What this page is doingStating the rule before the cases appear prevents either theory from being rescued after the fact.

Three Cases

Case A, Rosa, is an intensive care nurse on her third consecutive night shift. She has two school-age children and a partner who leaves for work at 7:00. She knows drowsy driving is dangerous and says so. She drives straight home after every shift because the children must be taken to school and no one else can do it.

Case B, Dev, is a respiratory therapist who sometimes naps in the hospital's two-bed nap room before driving home and sometimes does not. When asked, he says it depends on whether a bed is free when he finishes. His beliefs about drowsy driving do not change between mornings.

Case C, Ana, is a nurse in her first year. At orientation she heard a talk on drowsy driving and resolved to nap before driving after night shifts. She still says she intends to. On most mornings, she reports, she "ends up in the car on autopilot" and is halfway home before she remembers.

The Theory of Planned Behavior

Case A

The theory handles Rosa well. Her attitude toward driving straight home may be favorable overall, because the outcomes she values, getting her children to school and keeping her family's routine, outweigh the risk she acknowledges. Her subjective norm likely supports driving, since her partner and children depend on it. Above all, her perceived behavioral control over the alternative is low: she has no way to nap and still get the children to school. The theory predicts her intention and behavior without any addition (Ajzen, 1991).

Case B

Dev's case tests the theory's account of control. The theory allows perceived behavioral control to influence behavior directly when it reflects actual control. On mornings when the nap room is full, his actual control over napping is low and he drives; when a bed is free, control is higher and he naps. The explanation requires that his intention be conditional, "I will nap if a bed is free," which the theory can accommodate if the behavior is defined carefully. No addition is needed, though the explanation leans on actual control more than on the belief-based constructs that are the theory's core.

Case C

Ana's case is the hardest. She intends to nap, her attitude and norms favor napping after orientation, and nothing prevents her: the nap room is usually available. Yet she drives. The theory predicts that she will nap, and it is wrong. To explain her behavior, the theory must add something it does not contain in its basic form, such as habit or past behavior as a separate predictor, which some researchers have proposed and which critics regard as conceding the theory's limits (Sniehotta et al., 2014). The intention-behavior gap in Ana's case is exactly the kind that experimental evidence shows is common: changes in intention often produce smaller changes in behavior (Webb & Sheeran, 2006).

The COM-B Model

Case A

COM-B explains Rosa through opportunity and reflective motivation. Her physical opportunity to nap is absent because of the school run, and her social opportunity is shaped by family routines. Her reflective motivation weighs the children's needs against the risk. The model explains her behavior without addition and points to opportunity, such as childcare arrangements on the third night, as the place to intervene (Michie et al., 2011).

Case B

COM-B explains Dev through physical opportunity: the nap room's capacity determines whether the opportunity exists. The model treats opportunity as a direct influence on behavior, so his variation follows without requiring a conditional intention.

Case C

COM-B explains Ana through automatic motivation. Her reflective motivation favors napping, but the habit of walking to the car at the end of a shift, cued by the same time, route and car every morning, fires before reflection intervenes. Habits of this kind are triggered by stable context cues and can persist despite contrary intentions (Wood & Neal, 2007). The model contains automatic motivation as a core component, so no addition is needed.

What this page is doingShowing exactly where one theory needs an addition, and why, is what lets the comparison reach a verdict rather than a tie.

What Each Theory Would Do for Ana

The cases also show how the two accounts point to different help for the same person. For Ana, the planned behavior account would look for a weakness in her intention or her perceived control and, finding neither, would have little to suggest beyond strengthening her resolve. The COM-B account would suggest interrupting the habit at its cue: an implementation plan that ties napping to a specific moment, such as badge-out, or a nap room placed between her unit and the garage so the route itself changes. That difference matters for a workplace program, which needs remedies that work on mornings when good intentions do not.

Verdict and What It Costs

COM-B explains all three cases with its existing components; the theory of planned behavior explains two and needs an addition for the third. On this problem, COM-B has the broader reach. The verdict has costs. The theory of planned behavior offers precise measurement procedures and a strong record of predicting intentions; COM-B is a framework for diagnosis more than a theory with specified relationships among its parts, so it predicts less precisely. A study of Rosa's case alone might be better served by the planned behavior account's measurement tools. The comparison favors COM-B for the problem as a whole because the habitual, opportunity-dependent features of the drive home appear in two of three cases, and those are the features the planned behavior account handles least naturally.

References

Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50(2), 179-211. https://doi.org/10.1016/0749-5978(91)90020-T

Michie, S., van Stralen, M. M., & West, R. (2011). The behaviour change wheel: A new method for characterising and designing behaviour change interventions. Implementation Science, 6, Article 42. https://doi.org/10.1186/1748-5908-6-42

Sniehotta, F. F., Presseau, J., & Araujo-Soares, V. (2014). Time to retire the theory of planned behaviour. Health Psychology Review, 8(1), 1-7. https://doi.org/10.1080/17437199.2013.869710

Webb, T. L., & Sheeran, P. (2006). Does changing behavioral intentions engender behavior change? A meta-analysis of the experimental evidence. Psychological Bulletin, 132(2), 249-268. https://doi.org/10.1037/0033-2909.132.2.249

Wood, W., & Neal, D. T. (2007). A new look at habits and the habit-goal interface. Psychological Review, 114(4), 843-863. https://doi.org/10.1037/0033-295X.114.4.843

The Walden PHLT 8048 Week 5 instructions

The fifth assignment usually asks students to compare two leading theories against their behavior. Faculty expect a fair method, such as testing each theory against the same cases under the same rules, rather than a side-by-side list of constructs. Cases should be drawn from the behavior's real features and should include at least one that is hard for each theory. Each theory's explanation should use its own constructs accurately, and any addition a theory needs should be noted. Strong comparisons consider what each theory would recommend for intervention, since that is where differences matter most in practice. The verdict should follow from the cases and acknowledge what the favored theory gives up. Comparisons often run four to five pages with cases presented before analysis.

Inside the PHLT 8048 Week 5 example

The paper opens by stating the rule that each theory may use only its existing assumptions. Three composite cases are described. The planned behavior section explains the first case through attitude, norms and low perceived control, the second through the direct path from actual control, and shows that the third requires a habit extension, citing critics and intention-change evidence. The COM-B section explains the first case through opportunity and reflective motivation, the second through physical opportunity and the third through automatic motivation, citing habit research. A section contrasts what each theory would offer the third nurse. The verdict favors COM-B for reach and economy and names the planned behavior account's advantages in measurement and prediction.

PHLT 8048 Week 5 rubric: what earns full marks

Graders reward a comparison that is fair in method and decisive in conclusion. Comparisons that stack cases in favor of one theory, or misstate a theory's constructs, lose credit. Credit goes to cases that test each theory at its weak point, to accurate application of each theory's mechanisms, and to explicit accounting of additions. Connecting the explanations to intervention implications shows why the comparison matters. The verdict should follow from the case analysis and acknowledge the favored theory's costs. Citations should support key claims about mechanisms and evidence. Clarity matters: a reader should be able to see, case by case, how each theory performed and why the verdict follows.

Common PHLT 8048 Week 5 mistakes, and how to avoid them

Theory comparisons often list constructs side by side without testing anything. Build cases from your behavior that would challenge each theory, including one that is hard for the theory you expect to favor. Apply each theory using only its own constructs and note any addition it needs. Ask what each would recommend for the same person. Let the cases decide, and say what the winner costs. Write the cases before applying either theory, so the cases cannot be shaped to suit the answer. Comparisons of other theory pairs can follow the same case-based method.

Get a PHLT 8048 Week 5 example written to your instructions

Comparisons need the pair your prompt names; attach that prompt and its rubric along with the two theories, or say which you are choosing between. The Week 5 PHLT 8048 sample runs both on shared cases and ranks them against a stated test, returned inside 24 to 48 hours. There is no charge for the first.

More PHLT 8048 papers and PhD in Public Health samples

PHLT 8048 Week 5 questions, answered

Why use cases instead of comparing constructs directly?

Construct-by-construct comparison shows how theories differ in vocabulary; cases show whether those differences matter for the behavior. A case that one theory explains natively and the other only with a borrowed term is evidence, not description. You can still include a construct table, but the sample uses it to summarize what the cases revealed.

Is it fair to count a habit extension against planned behavior?

The paper argues that it is fair to record it, not to penalize the theory into irrelevance. Researchers often extend planned behavior with habit or past behavior, and the sample says so. What the test registers is that the core theory needed the addition for this case, which is informative when the case is the central feature of the problem.

Can a comparison end without choosing a theory?

In this course it often should, if selection is assigned to a later week. The sample ranks the two on its stated test and names what the ranking leaves open, such as measurement and intervention guidance. Where the prompt demands a choice this early, the ranking becomes a selection with those open questions stated as its risks.

Where can I find a free PHLT 8048 Week 5 sample paper?

The full Week 5 comparison is reproduced here, testing the theory of planned behavior and COM-B against three composite night-shift workers and ranking them on reach and economy.

Why does the first-year nurse matter most?

She intends to nap and faces no obstacles, yet drives home. That gap between intention and behavior is where the two theories differ most, since one must add habit and the other already includes it.