VisualDx supports visual clinical decision-making, DermNet provides dermatology reference and learning material, and iatroX offers broader clinical explanation and practice. The useful distinction is the task: describing a visible finding, investigating possible diagnoses, checking a condition reference or understanding the next decision. No image resemblance or generated differential confirms a diagnosis by itself.
This comparison is published by iatroX and includes its own products. It updates the existing VisualDx comparison using public descriptions checked on 20 September 2026. It does not report a diagnostic-accuracy test, and the teaching example below uses text rather than reproducing protected clinical images.
Visual reference involves more than recognising a photograph
As published on the review date, VisualDx combines a differential builder, clinical imagery across skin tones and body sites, and condition information that includes clinical and treatment considerations. It should not be described as an image collection with nothing to offer once a diagnosis is considered.
DermNet provides dermatology topics, imagery and educational resources, with professional material and other functions accessible through its current site. The relevant comparison is not paid diagnostic software versus a single static article. Inspect the actual resource and any applicable access conditions.
The availability of images can help a learner understand descriptive language and variation in presentation. It does not supply the history, examination or clinical context missing from a photograph. A confident label can still be poorly supported if the underlying description is wrong.
Start before the diagnostic label
An original fictional learner is shown a written description of an itchy eruption affecting several areas. Instead of naming the condition immediately, the learner has to identify what the description establishes: distribution, duration, symptoms and any stated morphological features. They then identify what has not been described.
This is a deliberate restraint. If the exercise begins with "This looks like eczema", every later search may be used to defend that first impression. A better opening is to separate the observation from the proposed interpretation. The learner can then use an authorised visual reference to improve the description, without claiming that this article has supplied a real image-based diagnosis.
For an educator adding imagery, use original or properly licensed material and retain the necessary permissions. Linking to a reference is not permission to reproduce its gallery or upload an image collection to another platform.
An unfamiliar rash and established eczema are different tasks
The older comparison usefully distinguished an unknown rash from a management question about established eczema. Keep that distinction, but do not turn it into a rule that a visual resource becomes irrelevant once a label is available.
For an unfamiliar presentation, a visual reference can help compare features and identify alternatives worth considering. The next question is which finding would distinguish those alternatives, and whether the case contains information requiring prompt clinical assessment. A longer list is not automatically a better differential.
For a fictional patient with an established eczema diagnosis, the unresolved issue might concern an unfamiliar description, a changed presentation, understanding a management recommendation or explaining the condition. The required resource changes with that question. Visual material may still help with communication; a clinical reference may help with the rationale; local or specialist guidance may be necessary for the real decision.
No particular treatment is recommended by these examples. They illustrate the difference between choosing a resource and deciding a patient's care.
Keep observation, interpretation and decision in separate columns
| Stage | An appropriate learning question | A premature conclusion to avoid |
|---|---|---|
| Description | What is actually visible or documented? | The image resembles a remembered diagnosis, so the diagnosis is established |
| Differential | Which possibilities fit, and which features do not? | Every item on a generated list is equally plausible |
| Discrimination | What missing information would change the ordering? | An unrecorded finding is absent |
| Reference check | Which source addresses this population and decision? | Any page about the condition supports the proposed action |
| Communication | How can the uncertainty be explained accurately? | A simple explanation requires hiding uncertainty |
This original worksheet can be used with permitted images, text cases or clinical teaching. It is not a diagnostic scoring system. Its purpose is to expose a jump in reasoning before the learner becomes invested in the final label.
Skin-tone coverage is important, but it is not an outcome claim
A visual resource should allow educators to consider variation rather than teach one appearance as universal. VisualDx explicitly describes varied imagery in its public product information. That is a relevant design and content feature, not proof that every user or every image classifier performs equally well across populations.
When evaluating a resource, inspect whether the chosen teaching material actually covers the population and presentation in question. Do not infer comprehensive representativeness from one example or from a headline library count. An evaluation would need a defined task, appropriate cases and reviewers before making comparative performance claims.
The same discipline applies to iatroX. Its general clinical reasoning functions should not be presented as validated image-diagnostic equivalents to specialist tools merely because they can discuss a dermatology question.
Where iatroX supports the surrounding reasoning
Ask-iatroX's September 2026 specification describes source-linked clinical reference. An appropriate use is to clarify terminology or investigate the reasoning behind a recommendation, while inspecting its source. A proposed learning prompt might ask which additional information would help distinguish two explanations in an original fictional case. It should not be presented as a verified product output.
The learning tools can then address a specific gap through relevant questions and Tutor discussion. For a specialty examination, use the appropriate bank and check whether additional visual teaching is needed. A written question about dermatology is not evidence of access to every specialist image library.
The UK iatroX learning package, as published on 20 September 2026, is £99 upfront annually or £29 monthly. Its value lies in the learning methods actually used, not a claim to replace VisualDx or DermNet across their specialist functions.
Which resource fits which reader?
For an image-led differential or a need for varied clinical appearances, examine the relevant specialist visual resource. For a condition overview and dermatology learning, DermNet is a useful starting point with its own scope and terms. For an unresolved clinical concept or a reasoning exercise, iatroX can complement those resources.
For a real patient whose presentation remains uncertain, the next step may be further assessment or specialist advice, not another subscription. The resource has done useful work when it helps the clinician identify that boundary rather than conceal it.
Frequently asked questions
Is VisualDx only useful before a diagnosis is considered?
No. Its current public description includes condition detail and treatment considerations as well as visual and differential support.
Can I reuse DermNet images in another tool or article?
Check the applicable image licence and permissions first. Public availability does not automatically permit copying, redistribution or uploading to a different service.
Is iatroX a validated substitute for an image-diagnostic system?
No such equivalence is established here. Its relevant role in this comparison is clinical explanation and learning around the visual assessment task.