| Course | HD420 Social Determinants of Health and Health Behavior |
|---|---|
| Unit | Unit 3 |
| Paper type | Behavior theory application |
| Length | About 660 words, 5 pages double-spaced |
| Format | APA 7 student paper |
| School | Purdue University Global |
| Program | BS in Health and Wellness |
| Updated | October 2026 |
Free sample paper for HD420 Unit 3
Every Belief Has an Address: A Unit 3 Behavior Theory Application of the Theory of Planned Behavior to Truck Drivers and Sleep Apnea Treatment
[Student Name]
Purdue University Global
HD420: Social Determinants of Health and Health Behavior
Unit 3 Behavior Theory Application
[Instructor Name]
[Date]
The trucking company, the drivers and their quotes are composite; the theory, the crash study and the social determinants review cited are real.
The Behavior
The behavior is nightly use of continuous positive airway pressure, a machine that keeps the airway open during sleep, by drivers diagnosed with obstructive sleep apnea. Untreated sleep apnea causes daytime sleepiness, and a study of a large trucking fleet found that drivers who did not adhere to employer-mandated treatment had a much higher rate of serious preventable crashes than matched controls (Burks et al., 2016). At the composite company, about [40] percent of diagnosed drivers use their machines for fewer than four hours on most nights by the third month.
The Theory
Ajzen's model places intention closest to action. Three inputs build intention: a driver's own judgment of the act, their sense of what coworkers and family expect, and their confidence that they can actually carry it out. Perceived control can also affect behavior directly when real control is limited (Ajzen, 1991).
Construct by Construct
Attitude. Drivers interviewed say the machine is noisy, the mask is uncomfortable and it "makes me feel like a sick old man." Some believe they sleep fine without it. Taken alone, these are attitudes a health educator might try to change with information.
Subjective norms. Drivers say other drivers joke about the machines, and some believe the company uses the diagnosis to cut their miles. A spouse who urges use at home has little influence on the road.
Perceived behavioral control. This is where most of the trouble sits. Drivers sleep in the cab's sleeper berth. Many trucks have no power outlet that runs with the engine off, and idling to power the machine breaks anti-idling rules at many truck stops. Batteries cost money the company does not cover. Cleaning the mask and tubing on the road is hard without running water.
What the theory records as a driver's low perceived control is, on inspection, a truck without a power outlet, a truck stop rule against idling and a battery the company will not buy.
Where Each Belief Comes From
Even the attitudes have roots in the job. The belief that the diagnosis cuts miles reflects a real policy: at this company, a diagnosed driver must show machine-use records to keep driving, and medical examiners often ask for the same records at certification, so a driver who cannot document use is parked until he can. The stigma among drivers reflects a workforce in which admitting a health problem can cost income. These are not misunderstandings to be corrected with a pamphlet. They are accurate readings of the conditions drivers work under, which is the point the social determinants literature makes about behaviors that seem individual (Braveman & Gottlieb, 2014).
What the Theory Explains Well
The theory correctly predicts that intention alone will not produce use when control is low. It also highlights subjective norms, which suggests that peer drivers who use their machines successfully could change what is seen as normal.
What It Leaves Out
The theory treats beliefs as the end of the explanation. It does not ask why perceived control is low. For truck drivers, the answer is equipment and policy, which a belief-focused program cannot change.
Implications for an Intervention
A program built only on the theory would target attitudes with education about crash risk and norms with peer stories. A program built on the theory plus the conditions it uncovered would also fund cab power inverters or batteries, negotiate parking at truck stops with shore power, and supply cleaning kits. The first approach works on beliefs; the second removes the reasons for them.
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
Braveman, P., & Gottlieb, L. (2014). The social determinants of health: It's time to consider the causes of the causes. Public Health Reports, 129(Suppl. 2), 19-31. https://doi.org/10.1177/00333549141291S206
Burks, S. V., Anderson, J. E., Bombyk, M., Haider, R., Ganzhorn, D., Jiao, X., Lewis, C., Lexvold, A., Liu, H., Ning, J., Toll, A., Hickman, J. S., Mabry, E., Berger, M., Malhotra, A., Czeisler, C. A., & Kales, S. N. (2016). Nonadherence with employer-mandated sleep apnea treatment and increased risk of serious truck crashes. Sleep, 39(5), 967-975. https://doi.org/10.5665/sleep.5734
What the HD420 Unit 3 assignment asks for
The third unit usually asks you to apply a named behavior theory to a specific health behavior in a specific population, explaining each construct with evidence and judging how well the theory accounts for the behavior. Applications typically run three to four pages. Marks follow an accurate account of the theory, each construct illustrated with concrete beliefs or data from the population, and a critical section on what the theory leaves out. Many sections reward linking individual-level constructs to the social and structural conditions behind them, which is the point of a determinants course. Cite the theory's original source and evidence on the behavior's consequences. End with implications for an intervention that follow from both the theory and its limits.
Inside the HD420 Unit 3 example
The paper defines the behavior and its stakes, citing a fleet study linking nonadherence with serious crashes. It summarizes the theory and its three determinants of intention, citing Ajzen. Three sections take attitude, subjective norms and perceived behavioral control in turn with drivers' own words. The highlighted sentence shows a construct resolving into a truck without a power outlet and a battery the company will not buy. A section traces even attitudes and norms to job conditions, citing the causes-of-the-causes review. Sections then weigh what the theory explains well and what it leaves out, and a final section contrasts an education-only program with one that changes equipment and parking.
Reading the HD420 Unit 3 grading rubric
Theory applications are commonly scored on accurate use of the theory, quality of evidence for each construct, critical analysis of the theory's limits and implications for intervention. Critical analysis often separates strong work, since applying constructs mechanically is easier than showing where they stop explaining. Accuracy rewards correct definitions and the relationship between intention and behavior. Evidence credit goes to concrete beliefs or figures from the population. Implications earn points when they follow from both the constructs and the conditions behind them. Citing the theory's primary source is expected. A paper that ties perceived control to physical and policy conditions shows the determinants thinking the course is building.
HD420 Unit 3 help: mistakes that cost points
One frequent misstep spends a page on definitions and a line on each construct's use. Another is treating every barrier as a belief to be corrected with education, even when the barrier is equipment or policy. Some students pick a behavior too broad for the theory, such as being healthy. Others cite the theory without its original source. Ending with recommendations that ignore the critique undercuts the paper. If you are applying a different theory, perhaps the Health Belief Model or social cognitive theory, share the behavior and population, and the constructs can be worked through with the conditions behind them. Forgetting to say which population the beliefs come from makes the application impossible to check.
Get an HD420 Unit 3 example written to your instructions
Which behavior and which theory has your HD420 section set for Unit 3? Send both with the prompt and rubric, plus any community data the instructions supply. A free first custom sample follows in 24-48h, applying that theory to the population pattern and ending on the condition the constructs trace back to. The paper above is an original model document written by our desk, not a submitted student paper and not an official Purdue University Global document.
More HD420 papers and BS in Health and Wellness samples
- HD420 Unit 1: Social Determinants Discussion Post
- HD420 Unit 2: Determinants Analysis
- HD420 Unit 4: Community Profile
- HD420 Unit 5: Access Barrier Study
- HD420 Unit 6: Seminar Reflection
- HD420 Unit 7: Health Equity Paper
- HD420 Unit 8: Policy Influence Analysis
- HD420 Unit 9: Intervention Level Proposal
- HD420 Unit 10: Determinants Report
HD420 Unit 3 questions, answered
Can I use the Health Belief Model instead?
If your prompt allows a choice, yes. The Health Belief Model's perceived barriers work much like perceived control in this example, and social cognitive theory's attention to environment suits a determinants course well. Whichever theory you apply, define its constructs from the original source and show what condition produced each one in the community you are describing.
Is it acceptable to criticize the theory?
In most sections it is expected. A behavior theory built around individual intention will underexplain patterns driven by price, supply or policy, and saying precisely where that happens shows you understand both the theory and the course's argument. Keep the critique specific to your case and avoid dismissing the theory wholesale, since it still explains part of the pattern.
What kind of data works for a community-level application?
Survey results reported as percentages, sales or purchasing data, utility records, school health surveys and county indicators all work, since each describes a population rather than one person. Local news archives can document events such as water notices. If only national data exists for a construct, say so and use it as an estimate, clearly flagged as one.
Where can I find a free HD420 Unit 3 sample paper?
The full Unit 3 paper is here, using Ajzen's model to examine why truck drivers stop using sleep apnea machines.
What is perceived behavioral control?
A person's sense of how easy or hard it is to perform a behavior. When real control is limited, it can predict behavior directly as well as through intention.