July 9, 2026
Getting Healthcare AI Right: Why Evaluation Is the Hard Part

Paola Rodriguez
MD, AI researcher, micro1
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Healthcare is one of the most exciting places to apply AI right now, and also one of the least forgiving. Companies are moving fast to put these systems into real clinical, operational, patient-facing, and research workflows, and the ambition makes sense, because the problems here are big and a better tool could genuinely help.
The ambition is rarely the hard part, though. The difficulty lies in the distance between a model that dazzles in a demo and one that still holds up on a Tuesday afternoon in the middle of a real workflow, and that distance tends to be wider than most teams expect. A system can sound fluent, cite the right guidelines, and still make a mistake that a trained clinician would catch in a second.
What we keep seeing is that the failures that actually matter are almost never about raw knowledge. They show up instead in judgment, in how a model handles ambiguity, whether it recognizes the limits of what is in front of it, and whether it can resist the pull to say more than the evidence supports. Healthcare AI has to be accurate, safe, useful, and grounded in real expertise all at once, and it has to be those things on the hard cases rather than just the easy ones. Getting there has less to do with finding one better model than with knowing, in detail, where a given system is ready and where it is not.
Where micro1 comes in
That knowing is the problem micro1 exists to solve. We help healthcare companies evaluate and improve their AI using expert human judgment, the kind that comes from people who actually do the work the model is being asked to support. In practice that means answering a handful of questions that turn out to be deceptively hard to answer alone: where a system performs well, where it fails, why it fails, and what expert data will close the gap.
Most teams have a rough feel for the first of those and very little visibility into the rest. The why is usually where progress stalls, because diagnosing a failure in a clinical setting takes someone who can look at an output and see not just that it is wrong, but which step in the reasoning broke and what a correct read would have looked like. That is the expertise we bring.
A benchmark for pathology reasoning
We recently put this to work in a benchmark built to study how frontier models reason through real anatomic pathology reports. Working alongside practicing pathologists, we assembled cases that cover what a working service actually sees, ranging from hematopathology and bone marrow workups to breast, thyroid, gastrointestinal, genitourinary, and dermatopathology specimens, along with biomarker studies. Rather than testing medical knowledge in isolation, we tested something narrower and harder: whether a model could pull the facts from a report exactly, preserve the diagnostic limits of the specimen, and stop short of conclusions the specimen did not support.
What stood out most was not which model scored highest, but the fact that two models could land at almost the same overall score while failing in completely opposite ways. Because we graded every claim against an expert-built rubric and read the full reasoning trajectory rather than only the final answer, those differences became visible, and we could point to the exact moment a model added a finding the specimen could not support, flattened an open differential, or stretched a report into a recommendation it had no business making. A single accuracy number hides all of that, whereas reading the trajectory is what actually tells you what to fix.
How we work with healthcare teams
That benchmark is really just one instance of a process we run with healthcare teams more broadly. The outline is simple, but each step does real work, and skipping any one of them is usually where evaluations go wrong.
It starts by pinning down the workflow. Before anything gets measured, we get specific about what the system is meant to do, who relies on its output, and what a good result looks like in that exact setting, since summarizing a pathology report and summarizing it without overstating what the specimen supports are very different jobs, and a vague goal only ever produces a vague evaluation.
From there we turn the workflow into a concrete evaluation framework, which means breaking the task into specific, gradeable criteria, the individual things a correct output must get right and the things it must not do, rather than leaning on an overall impression of quality. A good framework is what separates knowing that a model scored seventy percent from knowing which seventy percent.
Then we bring in the right experts, and by that we mean the people who do this work every day, a pathologist for pathology, a clinician for clinical notes, rather than generalist annotators, because they can tell the difference between an answer that is merely plausible and one that is actually correct. Their judgment is what the entire evaluation rests on, so the match between expert and task matters just as much as the framework itself.
With that in place, we evaluate the model's outputs against the criteria run by run, and just as importantly, we name the failure modes, the recurring patterns in how and why the system breaks down. Is it misreading a particular kind of input, overstating uncertainty, adding recommendations it was never asked for? A list of wrong answers is not worth much on its own, but a short list of named, repeatable failure patterns is something a team can actually act on.
Those patterns are also what let us build targeted data to fix them. Instead of generating generic volume, we create examples aimed squarely at the weaknesses the evaluation exposed, so the next version of the model improves where it genuinely struggled rather than where it was already strong. And because these systems keep changing, the work does not stop at a single report. Models get updated, prompts get rewritten, workflows shift, and a system that was reliable last quarter can quietly regress, so ongoing, expert-grounded evaluation is what catches that before it ever reaches a patient or a clinician.
What we're excited about
Looking ahead, we think the next wave of healthcare AI will be more workflow-specific, more expert-led, and more focused on reliability than the current one. The early excitement was about general capability, about what a model could do in principle, but the work that really pays off is narrower and more demanding, since it comes down to making a system dependable inside one well-defined workflow, with expertise built into how it is evaluated and improved.
The biggest opportunities sit right where the hard problems are. They live in the workflows where expert judgment is scarce and expensive, where a confident mistake is costly, and where reliability rather than novelty is what finally earns adoption.
Healthcare AI has enormous potential, and the models really are good and getting better, but getting it right takes more than a strong model. It takes rigorous evaluation, real expert judgment, and a clear sense of where a system is ready for production and where it still needs work. That is what will define the next chapter of healthcare AI: not just better models, but systems that are proven, reliable, and worthy of trust in the workflows that matter most.
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