Build More Accurate Document Review Budgets and Timelines with Metrics

This article originally appeared on the EDRM blog and is republished here for Exterro blog subscribers.

If you can’t measure it, you can’t manage it.

This well-known principle highlights an important truth for e-discovery professionals: to achieve repeatability, defensibility, and efficiency, document review must be treated as a structured business process. That means identifying key metrics, tracking them consistently, and using them to optimize performance.

Document review remains the most expensive phase of litigation, often accounting for the majority of e-discovery costs. As a result, reducing review costs is the most effective way to control overall legal spend—an ongoing priority for legal departments.

Why Metrics Matter in Document Review

There is a direct relationship between time and cost in document review. Reviewers are typically paid hourly, and the total cost is largely driven by the number of documents requiring review. Factors such as coding complexity and redaction needs can influence speed, but volume remains the primary cost driver.

The most effective way to control costs is to reduce the number of documents sent for review—by eliminating irrelevant and duplicate data before the process begins.

Three Key Metrics to Track

1. Data Volume

Track the total volume of potentially relevant data for each project, along with:

• Number of custodians
• Timeframe of preserved data

Over time, calculate the average data volume per custodian per month to improve forecasting accuracy.

2. Number of Documents

Data size doesn’t directly translate to document count. For example, one gigabyte can contain:

• Thousands to hundreds of thousands of documents, depending on file types

By tracking documents per gigabyte across projects, you can establish benchmarks for estimating future workloads.

3. Documents After Deduplication

Removing duplicate files can significantly reduce workload—often by up to 40%.

Tracking this reduction rate helps refine both cost and timeline estimates for future projects.

Estimating Cost and Timeline

A simple formula can help project document review costs:

Total documents ÷ Documents reviewed per hour × Hourly rate = Total cost

From this:

• Person-hours required = Total documents ÷ Review speed
• Estimated cost = Person-hours × Hourly rate
• Estimated timeline = Person-hours ÷ Number of reviewers

These calculations allow teams to forecast budgets and timelines early in the process.

Final Takeaway

By consistently tracking and analyzing document review metrics, organizations can:

• Improve budget accuracy
• Reduce unnecessary review work
• Optimize resource allocation
• Make better strategic decisions (including whether to settle a case)

Treating document review as a measurable, manageable process is essential for controlling costs and improving outcomes in modern e-discovery.

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