The Data

A county health department must choose between two diabetes prevention programs. Both have been evaluated. One delivers more health per dollar spent. The other costs less overall. Which should they fund? (Data are simulated for illustration.)

County Health Department Budget

The department has allocated funds for a new diabetes prevention initiative. Whatever they choose must fit within this envelope.

$2.5M
Annual prevention budget available

Program A Intensive Lifestyle Intervention

Cost per participant $4,200
Participants served 500
Total program cost $2.1M
Diabetes cases prevented 85
QALYs gained 127
Cost per QALY $16,535

Verdict: Highly cost-effective ($16,535/QALY is well below typical thresholds) and fits within budget.

Program B Community Health Worker Outreach

Cost per participant $800
Participants served 2,500
Total program cost $2.0M
Diabetes cases prevented 50
QALYs gained 75
Cost per QALY $26,667

Verdict: Still cost-effective ($26,667/QALY meets thresholds), lower total cost, reaches more people.

Both programs are "cost-effective" by standard criteria.

So why does it matter which one we choose? Because cost-effectiveness ratios alone do not tell us what we must give up to afford either option.

BIA Explained

Cost-effectiveness analysis asks "Is this a good use of money?" Budget impact analysis asks "Can we actually afford it?" These questions have different answers, and both matter for real decisions.

What Is Budget Impact Analysis?

Budget Impact Analysis (BIA) estimates the financial consequences of adopting a new intervention within a specific budget context. It answers:

  • How much will total spending change?
  • When will costs be incurred (Year 1 vs. Year 5)?
  • What existing programs might need to be cut or reduced?
  • Is this feasible given current constraints?

Unlike cost-effectiveness, BIA does not compare health gains to costs. It simply asks whether the organization can pay for what it wants to do.

Diagram comparing Cost-Effectiveness Analysis (value per dollar) with Budget Impact Analysis (total dollars needed) as complementary perspectives on the same intervention

CEA and BIA answer different questions. Both are needed for complete decision-making.

Understanding both analyses reveals hidden tradeoffs.

What happens when a highly cost-effective program is too expensive, or when an affordable program wastes resources?

The Tradeoffs

Programs can be cost-effective but unaffordable, or affordable but wasteful. Each combination creates a different policy challenge. Economists map these possibilities to clarify what each decision truly costs.

The Cost-Effectiveness vs. Affordability Matrix

Cost-Effective
Not Cost-Effective
Affordable
Ideal
Good value AND feasible. Implement.
Wasteful
Feasible but poor value. Redirect funds.
Unaffordable
Problematic
Good value but can't fund it. Seek resources or scale down.
Reject
Poor value AND unaffordable. Clear no.

V Cost-Effective + Affordable

The program delivers good value per dollar and total costs fit within available budgets. This is the goal.

Example: A vaccination program costs $15,000/QALY and requires $1.8M for full implementation. The county has $2M available. Proceed.

! Cost-Effective + Unaffordable

The program delivers excellent value, but the total price tag exceeds what the organization can spend. This forces difficult choices.

Example: A hepatitis C cure costs $12,000/QALY. But treating all eligible patients costs $50M. The budget is $5M. Scale down, phase in, or seek new funding?

$ Not Cost-Effective + Affordable

The program is cheap enough to implement, but the health gains per dollar are poor. Money could be better spent elsewhere.

Example: A wellness newsletter costs $300K annually and produces minimal measurable health improvement. The budget exists, but is this the best use?

X Not Cost-Effective + Unaffordable

The program is both poor value and too expensive. This is the clearest case for rejection.

Example: An experimental therapy costs $500,000/QALY and would require $20M to implement. Neither the value nor the budget supports adoption.

Real decisions require exploring both dimensions simultaneously.

What if you could adjust the scale or intensity of a program to change its budget impact while preserving cost-effectiveness?

Interactive Budget

Adjust program scale and intensity to see how budget impact changes. Notice that cost-effectiveness ratios stay constant while total costs fluctuate. This is the core insight: value and affordability are independent.

Program A (Intensive)
Program B (Outreach)
Budget Limit

Scaling changes total cost but not value per dollar.

This reveals why economists insist on answering both questions: a program's worth depends on both its efficiency and its feasibility in context.

Key Insight

These questions help clarify why "it works" and "we should fund it" are separate claims. They reveal the gap between knowing something is valuable and knowing whether we can actually do it.

Why doesn't cost-effectiveness guarantee adoption?

A $10,000/QALY intervention is excellent value. But if it requires $100M to implement and you have $5M, you cannot adopt it at full scale regardless of its efficiency.

What would you need to change to make a cost-effective program affordable?

What does "opportunity cost" mean here?

Every dollar spent on one program cannot be spent on another. Budget impact analysis forces you to confront what you give up when you choose.

If you fund Program A, what does Program B's forgone health gains represent?

When do cheap programs waste money?

An affordable program that delivers poor health value consumes budget that could have funded something more effective. Low cost does not equal good investment.

How would you evaluate a low-cost program that produces minimal health improvement?

How do time horizons matter?

Some programs have high upfront costs but generate savings later. BIA tracks cash flow over time, revealing whether short-term pain leads to long-term gain.

Should you favor programs with immediate returns or larger delayed benefits?

Concepts Demonstrated in This Lab

Budget Impact Analysis: estimating total financial consequences of a decision within a constrained budget
Cost-Effectiveness vs. Affordability: two independent dimensions that both matter for adoption
Opportunity Cost: what you give up when resources go to one program instead of another
Scale vs. Efficiency: changing program size affects total cost but not cost per outcome

Key Takeaway

Cost-effectiveness tells you whether a program is a good use of money. Budget impact tells you whether you can actually afford it. Answering "Is it worth it?" without asking "Can we pay for it?" leads to policies that look good on paper but never get implemented. Economists insist on both questions because real decisions happen under real constraints. Affordability and value are separate tests that programs must pass.