Cost per signed case is the right primary metric for lead vendor evaluation. But it has a well-known blind spot: it treats all signed cases as equal. A $1,200 cost per case looks the same whether the cases are soft-tissue fenders or surgical catastrophic injuries. The settlement values — and therefore the firm's revenue — are not remotely equal.
Severity distribution is the metric that corrects for this blind spot. It tells you not just how efficiently a vendor produces cases, but what kind of cases. And when you layer severity data on top of cost-per- case data, the vendor budget decisions become significantly more precise.
Related guide: See our complete guide to evaluating PI lead vendors — the 7 metrics that define vendor quality and how to build a vendor scorecard.
What Severity Distribution Is and Why It Matters
Severity distribution describes the breakdown of signed cases from a given vendor by injury category or case type. The specific categories your firm uses may vary, but a typical PI severity framework includes:
- High severity: Catastrophic injuries, TBI, spinal cord injury, surgical cases, wrongful death
- Mid severity: Surgically recommended cases (not yet operated), significant soft tissue with documented treatment, herniated disc cases
- Low severity: Minor soft tissue, disputed liability cases, cases with gap-in-treatment issues
The practical reason severity distribution matters: in most PI practices, high-severity cases produce 3 to 10 times the settlement revenue of low- severity cases — sometimes more. A vendor delivering 60% high-severity cases at a $1,400 cost per case is generating dramatically more revenue per marketing dollar than a vendor delivering 20% high-severity cases at a $1,000 cost per case.
Cost per case can't capture this difference. Severity distribution can.
How to Pull Severity Distribution Data
Severity distribution requires that your case management system categorizes cases by injury type or severity at the time of signing or early in case development. The specific field varies by platform — in LeadDocket it's often the case type or injury type field; in Filevine or Clio it may be a custom case category field.
The key data requirement: cases must be tagged with severity or case type consistently, and those tags must be linked back to the lead source that originated the case. Without that linkage — lead source to case type — you can't run a meaningful vendor-by-vendor severity analysis.
If your data is consistently captured, the report you need is simple: for each lead vendor, show the percentage of signed cases in each severity tier over the last 90 to 180 days.
Calculating a Severity-Adjusted Value per Case
Once you have severity distribution data for each vendor, you can build a severity-adjusted case value estimate. This doesn't require settlement data — it uses your firm's historical average settlement value per severity tier, which you likely already know even if you've never formalized it.
Start by defining average expected settlement value by tier based on your firm's historical outcomes. For example:
- High severity: $120,000 average settlement
- Mid severity: $40,000 average settlement
- Low severity: $12,000 average settlement
These are your firm's numbers — adjust them based on your actual case history. Then apply them to each vendor's severity distribution.
If Vendor A delivers cases with a distribution of 35% high, 45% mid, 20% low, the expected average case value is: (0.35 × $120,000) + (0.45 × $40,000) + (0.20 × $12,000) = $42,000 + $18,000 + $2,400 = $62,400 average case value.
If Vendor B delivers cases with a distribution of 15% high, 40% mid, 45% low, the expected average case value is: (0.15 × $120,000) + (0.40 × $40,000) + (0.45 × $12,000) = $18,000 + $16,000 + $5,400 = $39,400 average case value.
Now divide each vendor's cost per signed case by their expected average case value to get a marketing cost ratio:
- Vendor A: $1,200 CPC ÷ $62,400 expected value = 1.9% marketing cost ratio
- Vendor B: $1,000 CPC ÷ $39,400 expected value = 2.5% marketing cost ratio
Vendor A costs more per signed case, but its marketing cost as a percentage of expected case value is lower. Vendor B is cheaper per case but costs more relative to what that case is likely worth. Severity distribution flipped the ranking.
| Metric | Vendor A | Vendor B | |
|---|---|---|---|
| Cost Per Case | $1,200 | $1,000 | |
| High Severity % | 35% | 15% | |
| Mid Severity % | 45% | 40% | |
| Low Severity % | 20% | 45% | |
| Expected Case Value | $62,400 | $39,400 | |
| Marketing Cost Ratio | 1.9% | 2.5% |
Using Severity Distribution in Budget Decisions
Severity distribution changes budget decisions in two ways.
First, it identifies which vendors deserve higher budgets despite higher nominal cost per case. A vendor with a cost per case 20% above your firm average but a high-severity distribution that produces cases 60% more valuable than your average is a strong performer on the metric that actually drives revenue. Cutting their budget because their CPC looks high is a mistake the severity data makes visible.
Second, it identifies vendors whose low cost per case is misleading. A vendor at 85% of your average CPC but with a case mix that's 70% low-severity is not actually cheap — they're producing cases that will generate less revenue than your average case while consuming the same intake capacity, attorney time, and case overhead.
In budget allocation terms:
- Increase budget for vendors with high-severity distribution AND below-average or competitive cost per case. These vendors are your highest ROI marketing investments.
- Maintain or reduce budget for vendors with high-severity distribution but cost per case significantly above average. They produce good cases but at too high a cost — have the conversation about pricing or lead quality improvement.
- Reduce or exit vendors with low-severity distribution AND above-average cost per case. These vendors are your worst-performing investments regardless of how their invoice looks.
- Monitor carefullyvendors with low-severity distribution but below-average cost per case. They may be economically viable for volume, but they shouldn't capture more than a defined percentage of your total budget if your firm's strategy prioritizes higher-value cases.
The Conversation With Your Managing Partner
Severity-adjusted vendor data is one of the most compelling things you can bring to a managing partner budget conversation. It connects marketing spend directly to the revenue outcomes the partner cares about.
Instead of saying “Vendor A costs more per lead but produces better cases,” you can say: “Vendor A's cases have a projected average settlement value of $62,000. Vendor B's cases project at $39,000. At the same total marketing spend, allocating more budget to Vendor A is expected to increase firm settlement revenue by approximately $X over the next case cycle.”
That's the conversation that turns a budget request into a business case. It also gives the managing partner a framework to hold the marketing function accountable to outcomes — not just activity.
The Data Requirements to Make This Work
The severity distribution framework only works if the underlying data is reliable. Two data quality requirements need to be in place before you trust this analysis:
Consistent case categorization.If some cases are tagged with severity and others aren't, or if the tagging criteria vary by intake specialist, your severity distribution data will be wrong. Audit your case categorization practices before running this analysis.
Accurate lead source attribution.Severity distribution by vendor requires knowing which vendor each signed case came from. If your attribution is incomplete — cases where the lead source field is blank or logged as “unknown” — those cases will skew your vendor-level severity distribution. Clean up attribution before relying on severity distribution for budget decisions.
If your data isn't there yet, the right first move is investing in cleaner data capture practices before adding severity analysis on top. A severity distribution built on 60% of your cases will tell a different story than one built on 95%. Make sure you know which one you're looking at before you act on it.
Related guide: See our complete guide to PI lead generation by case type — how marketing economics change by practice area, with CPC benchmarks and channel strategies for each case type.