The Hidden Variable in Your Marketing ROI: Case Mix

You've done the hard work. You track cost per signed case by vendor. You know which sources convert and which ones burn budget. You're making allocation decisions based on real numbers, not vendor promises.

But there's a variable hiding inside your data that most PI firms never measure — and it can make two vendors with identical cost per case produce wildly different financial outcomes for your firm.

That variable is case mix.

Same Cost Per Case, Vastly Different Revenue

Consider a scenario that plays out at PI firms every month. You have two lead vendors, both delivering signed cases at $1,200 per case. Your vendor scorecard shows them as equivalent performers. Budget allocation is split evenly.

But when you look at what those cases actually resolve for 12 to 18 months later, the picture changes dramatically.

Vendor A consistently sends motor vehicle accident cases — rear-end collisions, intersection accidents, commercial vehicle incidents. These cases average $28,000 in settlement value at your firm.

Vendor B consistently sends premises liability cases — slip and falls, negligent security, dog bites. These cases average $11,000 in settlement value at your firm.

Both vendors cost you $1,200 per signed case. But for every dollar you spend with Vendor A, you get back $23.33 in settlement revenue. For every dollar with Vendor B, you get back $9.17. The marketing ROI difference is 2.5x— and it was completely invisible on your vendor scorecard.

Why Case Mix Is a Marketing Variable

Most PI firms treat case type as a legal variable — something that gets classified after the case is signed and handed to an attorney. But case type is determined upstream, at the marketing and lead generation level. The lead source determines which case types enter your pipeline.

A Google Ads campaign targeting “car accident lawyer near me” produces a fundamentally different case mix than a mass media campaign on daytime television. A legal directory listing optimized for “premises liability attorney” produces a different mix than a pay-per-call vendor specializing in trucking accidents.

Your marketing spend is not just buying lead volume. It's buying a specific distribution of case types. That distribution — the percentage of auto accidents vs. premises liability vs. medical malpractice vs. product liability — determines your firm's revenue potential months before a single case settles.

When you choose to allocate $30,000 per month to a vendor, you are implicitly choosing which case types will fill your pipeline. If you don't measure case mix by source, that choice is invisible. You can't optimize what you can't see.

A Worked Example: $120,000 Monthly Budget, Two Paths

Let's make this concrete. Your firm spends $120,000 per month on lead generation, split evenly between two vendors at $60,000 each. Both deliver signed cases at $1,200 cost per case. Each vendor produces 50 signed cases per month, for 100 total.

Now consider what happens if you reallocate. Instead of a 50/50 split, you move to 75/25 — $90,000 to Vendor A and $30,000 to Vendor B.

• Vendor A now produces 75 cases at $28,000 average settlement = $2,100,000 in projected revenue
• Vendor B now produces 25 cases at $11,000 average settlement = $275,000 in projected revenue
• Total projected revenue: $2,375,000 on the same $120,000 monthly budget

Compare that to the original 50/50 allocation, which produced $1,950,000 in projected revenue. The reallocation adds $425,000 per month in projected settlement value — over $5 million per year— without spending a single additional dollar on lead generation.

That's the power of measuring case mix. Not a marginal improvement. A structural one.

How to Measure Case Mix by Source

Measuring case mix requires connecting two data sets that most PI firms keep in separate systems: lead source attribution and case type classification. Here's what to track for each vendor and lead source.

Case Type Distribution

For every lead source, you need to know the percentage breakdown of signed cases by type. At minimum, track these categories:

• Motor vehicle accidents (passenger car, motorcycle, commercial vehicle, rideshare)
• Premises liability (slip and fall, negligent security, dog bite)
• Medical malpractice
• Product liability
• Wrongful death
• Workers' compensation (if your firm handles it)

If 80% of a vendor's cases are premises liability and only 10% are auto accidents, that's a fundamentally different revenue profile than a vendor sending 70% auto and 15% premises — even at the same cost per case.

Severity Distribution Within Case Types

Case type alone isn't enough. Within auto accidents, there's a massive difference between a soft tissue rear-end collision ($8,000 to $15,000 settlement range) and a multi-vehicle commercial truck accident with surgery ($75,000 to $300,000+ settlement range).

Track severity tiers by source. A three-tier system works for most firms:

• Tier 1 (Low complexity):Soft tissue, no surgery, short treatment — projected settlement under $15,000
• Tier 2 (Moderate complexity):Moderate injury, possible surgery, extended treatment — projected settlement $15,000 to $50,000
• Tier 3 (High complexity):Serious injury, surgery, long-term impact — projected settlement above $50,000

When you overlay severity distribution on top of case type distribution, you get a clear picture of revenue quality by source. A vendor sending mostly Tier 1 auto cases at $1,200 per case is a very different investment than a vendor sending mostly Tier 2 auto cases at $1,200 per case.

What Changes When You Optimize for Revenue Quality

Once you start measuring case mix, your vendor evaluation framework shifts. Cost per case becomes the floor of your analysis, not the ceiling. Here's what changes in practice.

Budget conversations with partners get easier.When you can show that reallocating $30,000 from one vendor to another — at the same cost per case — adds $425,000 per month in projected settlement revenue, the conversation moves from “justify this spend” to “how fast can we move the budget.”

Vendor negotiations become more precise.Instead of asking a vendor to “improve lead quality,” you can say: “Your case mix is 65% premises liability. We need to see that shift toward auto accidents, or we need a lower cost per case to justify the settlement value your cases produce.” That's a specific, data-backed conversation — not a vague complaint.

New vendor evaluation improves.Before committing budget to a new lead source, you can ask: “What case types does your inventory skew toward?” A vendor who can't answer that question — or whose answer doesn't match your revenue goals — is a risk you can quantify before you spend a dollar.

Your pipeline becomes a revenue forecast, not just a case count. When you know the case mix and severity distribution entering your pipeline each month, you can project settlement revenue 12 to 18 months out with real confidence. That changes how your firm plans hiring, overhead, and growth.

The Next Level of Vendor Evaluation

Cost per case was the first step. It moved PI firms from tracking vanity metrics like cost per lead to tracking what actually matters: how much it costs to acquire a signed client. That was the right move, and firms that made it gained a real competitive advantage.

But cost per case assumes all cases are created equal. They're not. A $28,000 auto case and an $11,000 premises case are different financial instruments — and your marketing spend is buying a specific mix of them every month.

The firms that measure case mix by source will be the ones who extract the most revenue from every marketing dollar. Not because they spend more, but because they know exactly what their spend is buying — and they optimize accordingly.

Cost per case tells you how much you paid. Case mix tells you what you bought. The firms that track both will outspend and outperform the ones that only track one.

If you're already tracking cost per case, you're ahead of 80% of PI firms. The question is whether you're ready to see what that metric has been hiding. Case mix is not a secondary metric. It's the variable that determines whether your marketing investment produces adequate returns or exceptional ones.

Start by pulling settlement data by lead source for the last 12 months. Classify by case type. Calculate average settlement value per source. The numbers will tell you exactly where your budget should go next.