HLTH 4530 Week 8 Cost-Effectiveness Write-Up Example

Screening Older Men for Abdominal Aortic Aneurysm: A Letter Inviting Them to a Booked Scan Versus a Bedside Ultrasound at Routine Visits, Both Compared With Usual Care, and the Inputs That Would Drive the Ratio

Student Name

Walden University

HLTH 4530: Healthcare Economics From a Population Health Perspective

Instructor Name

Month Day, Year

Screening Older Men for Abdominal Aortic Aneurysm: A Letter Inviting Them to a Booked Scan Versus a Bedside Ultrasound at Routine Visits, Both Compared With Usual Care, and the Inputs That Would Drive the Ratio

The Question

Compared with usual care, what does each of two screening approaches add in cost and in health for men between 65 and 75 who have smoked at any point, in a composite regional health system, Riverbend Health?

The Population and Why It Matters

An abdominal aortic aneurysm is a widening of the main artery in the abdomen, usually defined as a diameter of 3.0 cm or more. Most cause no symptoms until they rupture, and rupture is often fatal. Federal preventive guidance calls for a single ultrasound for men between 65 and 75 with any history of smoking, judging the net benefit moderate with moderate certainty (US Preventive Services Task Force [USPSTF], 2019). Riverbend's primary care practices care for about 9,000 men who meet that description.

The Comparator: Usual Care

Usual care at Riverbend is opportunistic. A clinician may order an ultrasound when a patient raises the question, when a pulse is felt during an examination or when the electronic record prompts it, but there is no organized outreach. Some eligible men are screened this way; most are not. Every cost and every health gain below is measured against this baseline, not against doing nothing at all.

Option A: Invitation to a Booked Scan

Every eligible man receives a letter offering a specific appointment for an ultrasound at one of the system's imaging centers, with a reminder call and a simple way to change the time. Men found to have an aneurysm enter a surveillance program with repeat scans, and those whose aneurysm reaches a size threshold are referred for elective repair.

Option B: Bedside Ultrasound at Routine Visits

Primary care medical assistants are trained to perform a brief point-of-care ultrasound of the aorta during an eligible man's routine visit. Positive or uncertain scans are confirmed by formal imaging. This option requires no separate trip but reaches only men who come in for a visit during the screening period.

Two Concepts

The Quality-Adjusted Life Year

A quality-adjusted life year, or QALY, counts years of life weighted by their quality. Twelve months lived in full health score 1.0; a year lived with a condition that reduces quality of life counts as less than one. QALYs allow very different health gains, a death prevented or a year of reduced anxiety, to be added together on one scale.

The Incremental Cost-Effectiveness Ratio

The incremental cost-effectiveness ratio, or ICER, divides the extra cost of an option by the extra health it produces, each measured against the comparator. If Option A costs more than usual care and produces more QALYs, its ICER is the extra cost per extra QALY. Current methods guidance asks analysts to present a payer-and-provider view alongside a wider societal one, so that patients' own travel and time do not drop out of the account (Sanders et al., 2016).

What the Evidence Says About Screening Itself

The strongest evidence comes from the Multicentre Aneurysm Screening Study in the United Kingdom, which randomly assigned 67,800 men aged 65 to 74 to an invitation to ultrasound screening or to no invitation. In the first report, 80% of invited men attended, aneurysm-related deaths were 42% lower in the invited group, and 30-day mortality was 6% after elective surgery compared with 37% after emergency surgery (Ashton et al., 2002). At 10 years, the relative reduction in aneurysm-related deaths was 48%, and the trial's own analysis estimated an incremental cost of about £7,600 per life year gained, a figure that became more favorable over time (Thompson et al., 2009). That ratio is for invitation versus no invitation in the United Kingdom, per life year rather than per QALY; it cannot be carried over to Riverbend, but it shows that invitation-based screening can be cost-effective where attendance is high.

The Inputs That Would Drive Riverbend's Ratios

Without local data, the write-up identifies the inputs that would most change each option's ICER.

Attendance or reach. Thompson et al. (2009) stress that benefit depends on a high initial attendance rate. Option A's ratio depends on how many invited men attend. Option B's ratio depends on how many eligible men make a routine visit during the period and how many of those visits include the scan. A program that reaches few men spreads its fixed costs over little health gain.

Prevalence. Task force reviewers note that aneurysm prevalence has fallen among screened men in several European countries and is uncertain in the United States (USPSTF, 2019). Lower prevalence means more scans per aneurysm found and a higher cost per QALY.

Repair outcomes. The health gain from screening comes mainly from converting deaths after rupture into elective repairs. The gap between elective and emergency surgical mortality in the trial, 6% against 37%, is the engine of benefit; a system with worse elective outcomes gains less.

Scan accuracy and confirmation. Option B depends on trained assistants. Missed aneurysms reduce benefit, and false positives add confirmation scans and anxiety, which lower quality of life for a time.

Surveillance costs. Many screen-detected aneurysms are small and require years of repeat scans, which add cost before any health gain is realized.

Costs to patients. Option A requires a separate trip for most men; Option B does not. From a societal perspective, travel and time could favor Option B even if its health-sector cost per scan is higher.

How the Options Are Likely to Compare

Option A resembles the intervention that the trial evaluated, so its benefits are better established, and its attendance can be managed through reminders. Option B could reach men who would not attend a separate appointment and saves them a trip, but it misses men who do not visit during the period and depends on the accuracy of scans performed by newly trained staff. A full analysis would model both against usual care, with Riverbend's attendance, prevalence and surgical outcomes, and report a ratio for each. Until then, the evidence supports the conclusion that organized screening of eligible men is likely to be good value compared with opportunistic screening, and that the choice between the two delivery methods turns on reach and accuracy.

Limits

Riverbend is composite, and the trial evidence comes from men screened in the United Kingdom in the 1990s, when aneurysm prevalence was higher. The write-up deliberately reports no ICER for Riverbend, because doing so would require inputs it does not have.

References

Ashton, H. A., Buxton, M. J., Day, N. E., Kim, L. G., Marteau, T. M., Scott, R. A. P., Thompson, S. G., & Walker, N. M. (2002). The Multicentre Aneurysm Screening Study (MASS) into the effect of abdominal aortic aneurysm screening on mortality in men: A randomised controlled trial. The Lancet, 360(9345), 1531-1539. https://doi.org/10.1016/S0140-6736(02)11522-4

Sanders, G. D., Neumann, P. J., Basu, A., Brock, D. W., Feeny, D., Krahn, M., Kuntz, K. M., Meltzer, D. O., Owens, D. K., Prosser, L. A., Salomon, J. A., Sculpher, M. J., Trikalinos, T. A., Russell, L. B., Siegel, J. E., & Ganiats, T. G. (2016). Recommendations for conduct, methodological practices, and reporting of cost-effectiveness analyses: Second Panel on Cost-Effectiveness in Health and Medicine. JAMA, 316(10), 1093-1103. https://doi.org/10.1001/jama.2016.12195

Thompson, S. G., Ashton, H. A., Gao, L., & Scott, R. A. P. (2009). Screening men for abdominal aortic aneurysm: 10 year mortality and cost effectiveness results from the randomised Multicentre Aneurysm Screening Study. BMJ, 338, b2307. https://doi.org/10.1136/bmj.b2307

US Preventive Services Task Force. (2019). Screening for abdominal aortic aneurysm: US Preventive Services Task Force recommendation statement. JAMA, 322(22), 2211-2218. https://doi.org/10.1001/jama.2019.18928