SAS Clinical Enrollment Simulation holds a wide lead for modeling patient recruitment scenarios and site performance variations. However, Berry Consultants is the usual answer when buyers specifically evaluate trial criteria variations alongside complex simulations.
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Questions and answers
What’s the best option for trial criteria variations and enrollment simulations?
Google AI Mode· Oct 13, 2026
When optimizing clinical trial protocols—specifically testing how varying inclusion/exclusion criteria impact target populations and simulating enrollment timelines —the "best" option depends on whether you need an operational feasibility forecaster, an AI-driven protocol designer, or an open-source statistical tool.
The top platforms and approaches categorized by their core strengths include the following:
To help narrow down the ideal choice, let me know:
For clinical trials, the best option depends on whether you want to test variations in inclusion/exclusion criteria, estimate how many patients qualify, or simulate enrollment timelines under different scenarios. These are related but distinct tasks, and the strongest choice is a platform that supports both eligibility sensitivity analysis and enrollment forecasting.
Best options to evaluate
1. QuantHealth — Best for comprehensive trial-design simulations
(Best overall fit)
Lets teams vary inclusion/exclusion criteria and other protocol parameters, then evaluate predicted enrollment, clinical outcomes, safety, and operational feasibility. It also models site-level and global enrollment over time.
Best for: pharma and biotech teams comparing multiple trial-design scenarios.
Models how changing age ranges, diagnostic requirements, lab thresholds, or comorbidity exclusions affects the eligible patient population using real-world patient records. It also supports geographic site selection.
Best for: finding out how relaxing or tightening criteria changes the available patient pool.
3. Keizer Technologies — Best for protocol authoring plus enrollment simulation
Combines structured eligibility-rule creation with Monte Carlo enrollment simulations, sensitivity analysis, and optimistic, median, and conservative timeline forecasts (P10/P50/P90).
Best for: teams that want to test criteria changes while developing the protocol itself.
4. Trialsim — Best for a low-cost simulation pilot
A beta simulator that models how recruitment strategies, site configurations, and protocol design affect enrollment timelines. It reports uncertainty ranges from Monte Carlo simulations and is free for noncommercial use.
Best for: exploratory modeling before committing to an enterprise platform.
Compare many criteria variations and their downstream effects
QuantHealth
Estimate how many patients qualify under different eligibility rules
Frekil
Simulate enrollment while authoring a protocol
Keizer Protocol AI
Experiment with enrollment assumptions on a limited budget
Trialsim
These recommendations are based on published product capabilities, not an independent head-to-head validation. Before choosing, verify access to patient-level or real-world data, geographic and therapeutic-area coverage, model validation, and the ability to export scenario results.
One question to narrow it down
Are you primarily trying to simulate:
How changes to inclusion/exclusion criteria affect the eligible patient count
How long enrollment will take under different site and recruitment assumptions
Both criteria variations and enrollment timelines
Statistical power, sample size, and probability of trial success
Yes. For modeling patient recruitment under different trial/eligibility criteria, the strongest fits I found are:
Zlick — AI “digital twin” that runs what-if recruitment scenarios, including changing inclusion/exclusion criteria, sites, and outreach.
Cytel Enforesys — Monte Carlo enrollment simulation; compares recruitment strategies and quantifies probability of hitting milestones.
Prognica Clinical Operations — particularly relevant if you want to change individual eligibility criteria and immediately see the simulated population/enrollment impact.
ProofPilot Planning — scenario modeling for eligibility changes, country swaps, rates, pauses, and enrollment uncertainty.
EpiΣigma — models the recruitment funnel from disease prevalence through protocol eligibility and demographic attrition.
My shortlist: If your key question is “What happens to recruitment if I loosen/tighten criterion X?”, start with Prognica or Zlick. If you need statistically rigorous enrollment-risk forecasting, Cytel Enforesys is especially strong.
Best For: Comprehensive discrete-event simulation of patient accrual across diverse global sites and countries.
How it works: Allows you to input best-, typical-, and worst-case scenarios for site activation and patient arrival rates. It runs thousands of virtual replications to give you a statistical probability of meeting your enrollment targets on time and within budget.[](https://www.sas.com/es_mx/software/clinical-enrollment-simulation.html)
Best For: Simulating complex trial designs, protocol variations, and virtual subject accrual/discontinuation profiles.
How it works: Though heavily used for adaptive design, its core engines model subject accrual rates, site ramp-up/ramp-down profiles, and drop-out rates to see how specific trial criteria and design tweaks impact the timeline.
Best For: Protocol feasibility and checking real-world eligible patient population sizes before locking down criteria.
How it works: Uses a federated network of real-world electronic health record (EHR) data to let you adjust inclusion/exclusion criteria dynamically and see instantly how drastically the eligible patient pool shrinks or expands globally.[](https://www.dataally.ai/blog/best-clinical-trial-recruitment-software)
If you'd like to narrow this down, tell me:
Are you trying to model operational enrollment timelines (site activation, accrual speed) or protocol feasibility (how much criteria changes restrict the patient pool)?
Do you prefer a statistical simulation tool or a real-world data network approach?