| Course | HLTH 8745 Health Psychology |
|---|---|
| Week | Week 10 |
| Paper type | Trial critique |
| Length | About 570 words, 5 pages |
| Format | APA 7 student paper |
| School | Walden University |
| Program | PhD in Public Health |
| Updated | October 2026 |
Free sample paper for HLTH 8745 Week 10
Trial Critique: A Teaching-Construction Trial of Group Cognitive Behavioral Therapy for Irritable Bowel Syndrome Against a Waiting List, Read Against Its Own Design for What It Controlled, What It Measured and Whether Any Brain-Gut Mechanism Was Observed
Student Name
Walden University
HLTH 8745: Health Psychology
Instructor Name
Month Day, Year
Trial Critique: A Teaching-Construction Trial of Group Cognitive Behavioral Therapy for Irritable Bowel Syndrome Against a Waiting List, Read Against Its Own Design for What It Controlled, What It Measured and Whether Any Brain-Gut Mechanism Was Observed
The Trial
The trial under review is a teaching construction. It randomized 120 adults with irritable bowel syndrome to eight weekly sessions of group cognitive behavioral therapy or to a waiting list. At the end of treatment, 58% of the therapy group and 22% of the waiting-list group reported adequate relief of symptoms. The discussion credited the brain-gut axis, arguing that therapy reduced symptoms by calming signaling between the central nervous system and the gut. This critique reads the trial against its own design.
What the Comparison Controlled
A waiting list controls for the passage of time and for regression to the mean, since people tend to enroll when symptoms are at their worst. It does not control for attention, expectation, group support or the credibility of receiving a treatment. Freedland et al. (2011) discussed how the choice of control condition in behavioral trials determines what a comparison can show, and how weak controls can inflate apparent effects. Against a waiting list, any credible treatment delivered with weekly attention might produce improvement.
A stronger comparison exists in the literature. Lackner et al. (2018) compared cognitive behavioral therapy with an education control that matched for contact and attention, and found that more patients receiving therapy reported moderate to substantial improvement in symptoms two weeks after treatment, 61.0% against 43.5% by patient rating. That trial shows therapy can outperform an attention control, but the 43.5% improvement in the education group shows how much improvement occurs without specific therapy.
What the Outcome Measured
The outcome was a single global question about adequate relief. It is patient-reported and therefore sensitive to expectation, and patients in the therapy group knew they were receiving treatment while those on the waiting list knew they were not. Without blinding, which is difficult in behavioral trials, a subjective outcome is especially vulnerable to bias. The trial did not report symptom diaries, specific symptom scores or functional measures that might be less affected by expectation.
Whether Any Mechanism Was Observed
The discussion credited the brain-gut axis, but the trial measured nothing that would show a mechanism. It collected no measures of visceral sensitivity, gut motility, stress physiology or brain activity, and it did not measure the cognitive targets of therapy, such as catastrophizing about symptoms. Drossman (2016) described irritable bowel syndrome under the Rome IV criteria as a disorder of gut-brain interaction, a framework that makes the brain-gut explanation plausible. Plausible is not observed. A trial that wants to credit a mechanism needs to measure the proposed mediator and show that it changed before symptoms did.
Table 1
What the Trial Claims Against What Its Design Supports
| Claim | Supported by the design? | What would be needed | |
|---|---|---|
| Therapy improves symptoms | Partly; against a waiting list only | Attention-matched control | |
| Improvement is due to therapy content | No | Active control and measured targets | |
| Improvement works through the brain-gut axis | No | Measured mediator, such as visceral sensitivity, assessed over time | |
Requirements follow standard reasoning about control conditions and mediation in behavioral trials.
Conclusion
The trial supports a modest claim: people offered group therapy reported more relief than people waiting. It does not show that the therapy's content caused the difference or that the brain-gut axis was involved.
References
Drossman, D. A. (2016). Functional gastrointestinal disorders: History, pathophysiology, clinical features, and Rome IV. Gastroenterology, 150(6), 1262-1279. https://doi.org/10.1053/j.gastro.2016.02.032
Freedland, K. E., Mohr, D. C., Davidson, K. W., & Schwartz, J. E. (2011). Usual and unusual care: Existing practice control groups in randomized controlled trials of behavioral interventions. Psychosomatic Medicine, 73(4), 323-335. https://doi.org/10.1097/PSY.0b013e318218e1fb
Lackner, J. M., Jaccard, J., Keefer, L., Brenner, D. M., Firth, R. S., Gudleski, G. D., Hamilton, F. A., Katz, L. A., Krasner, S. S., Ma, C.-X., Radziwon, C. D., & Sitrin, M. D. (2018). Improvement in gastrointestinal symptoms after cognitive behavior therapy for refractory irritable bowel syndrome. Gastroenterology, 155(1), 47-57. https://doi.org/10.1053/j.gastro.2018.03.063
HLTH 8745 Week 10 instructions, in plain terms
Students critique a published or constructed trial of a behavioral intervention. Faculty expect the critique to examine the control condition, the outcome measure and any mechanistic claims, asking in each case what the design can support. The strongest critiques compare the trial with a stronger design in the literature, showing how a different control changes the size of an effect. Faculty value attention to blinding and to subjective outcomes, since behavioral trials are especially vulnerable to expectation. Claims about mechanisms should be tested against whether a mediator was measured and shown to change before the outcome. A table matching claims to the evidence the design provides is effective. The conclusion should state the modest claim the trial does support.
How this HLTH 8745 Week 10 example is built
The critique opens by labeling the trial as a teaching construction and stating its results and mechanistic claim. A section on the comparison explains what a waiting list controls and does not, citing Freedland and colleagues, and contrasts Lackner and colleagues' trial with an education control. A section on the outcome discusses the single patient-reported relief question and lack of blinding. A section on mechanism cites Drossman on the Rome IV view of gut-brain interaction and explains that no mediator was measured. Table 1 lists three claims with whether the design supports them and what would be needed. The conclusion states the modest claim the trial supports.
HLTH 8745 Week 10 rubric: what earns full marks
Precision decides this grade: each criticism has to connect to a feature of the trial's design. Saying the trial was small or unblinded earns modest credit. Credit rises when the critique explains what the control condition rules in and out and shows, with another trial, how an active control changes results. Faculty value attention to outcome measurement and to the gap between a plausible mechanism and an observed one. A table matching claims to evidence earns credit for clarity. The strongest critiques end with the claim the trial does support rather than dismissing it. Accurate reporting of comparison trial results is checked. Labeling the constructed trial clearly is expected.
HLTH 8745 Week 10 help: mistakes that cost marks
Trial critiques often list standard limitations, such as sample size and lack of blinding, without connecting them to the trial's claims, so the reader cannot tell which limitation matters for which conclusion. To write a stronger critique, take each claim the authors make and ask what the design would need to support it. Look at what the control condition controls. Check whether the outcome is subjective and whether participants knew their group. If the authors credit a mechanism, look for a measured mediator. Find a stronger trial to compare. State the claim the trial does support. A critique of the trial your course assigns can be drafted claim by claim.
Get a HLTH 8745 Week 10 example written to your instructions
Attach the assigned trial report with the critique prompt and rubric. You get back a critique that states the design neutrally, weighs the comparator before anything else, and separates what the trial established from the mechanism its authors proposed. The trial in the sample is fictional. It arrives in 24 to 48 hours; the first is without charge.
More HLTH 8745 papers and PhD in Public Health samples
- HLTH 8745 Week 1: Ulcer Explanation Post
- HLTH 8745 Week 2: Wound Healing Mechanism Brief
- HLTH 8745 Week 3: Allostatic Load Analysis
- HLTH 8745 Week 4: Planned Behavior Model Application
- HLTH 8745 Week 5: Cortisol Measurement Critique
- HLTH 8745 Week 6: Cardiac Depression Peer Reply
- HLTH 8745 Week 7: Medication Adherence Analysis
- HLTH 8745 Week 8: Illness Representation Case
- HLTH 8745 Week 9: Fear-Avoidance Pain Analysis
- HLTH 8745 Week 11: Stress and Infection Mechanism Paper
- HLTH 8701 Week 10: Attribution Across Cultures Post
- HLTH 8574 Week 10: Evidence Origin Peer Replies
- HLTH 8573 Week 10: Age-Specific Peer Replies
- HLTH 8560E Week 10: Data Constraints Memo
HLTH 8745 Week 10 questions, answered
Is a waiting-list control a weak design?
It answers a narrower question than people often assume. A waiting list shows whether a program does better than no program over the same period. It cannot show which part of the program produced the change, because attention and expectation differ between arms. The sample treats the design as legitimate for its question and critiques the discussion for reaching beyond it.
What would measuring the mechanism have required?
Measures of the proposed mediator taken during the trial, such as gut sensitivity or symptom-related anxiety, collected often enough to show that change in the mediator came before change in symptoms. The sample describes this in general terms. Your critique can propose it without designing a full study, which is usually the right level of detail for this assignment.
Can the critique conclude that the program works?
It can conclude what the trial showed: that people offered the program reported more improvement than people waiting. Whether the cognitive techniques caused that improvement, and through what route, remains open. The sample states both halves plainly, and graders tend to reward that division over either a verdict of success or a dismissal of the evidence.
Where can I find a free HLTH 8745 Week 10 sample paper?
This page shows the complete Week 10 trial critique, reading a constructed trial of group cognitive behavioral therapy for irritable bowel syndrome against its waiting-list control, outcome and mechanistic claim, with three references.
How did an active control change the results in a real trial?
In Lackner and colleagues' trial, 61.0% of patients receiving cognitive behavioral therapy reported moderate to substantial improvement two weeks after treatment, compared with 43.5% in an education control, a smaller gap than a waiting-list comparison suggests.