← ATOF interactive
🧮 Calculator📖 Methods⚠ LimitationsBrief · v0.1
Government brief

ATOF: making risk-stratified melanoma screening deliverable

Why

The National Targeted Skin Cancer Screening Roadmap sets out the case for a risk-stratified approach: invitations would go to people above a chosen 10-year risk threshold rather than to every age-eligible adult. Choosing that threshold is both a clinical decision (what is the model worth?) and an operational one (can the workforce deliver?).

Choosing a national threshold on clinical grounds alone risks recommending a policy that some Australian regions could not deliver in practice. The regions least able to absorb the implementation burden are often those with the highest disease and lowest workforce density. That is an equity consideration the threshold debate should make explicit.

88
SA4 regions in Australia
ABS Statistical Area Level 4
53%
of QLD SA4s have zero dermatologists
Lindsay 2026
67-76%
of melanoma in situ may be overdiagnosis
Lindsay 2024
1.5×
disparity in minimum feasible threshold
Q1 vs Q5 SEIFA quintile

What ATOF does

ATOF is an interactive decision-analytic tool. It brings three usually-separate evidence streams into one screen, so a policy maker can see the trade-offs before committing to a threshold.

  1. Clinical net benefit. For each validated Australian risk model (QSkin MP16/MP7, MIA/Vuong, NCI MBRAT, Cho), ATOF shows where the model is actually clinically useful, by Vickers and Elkin's decision-curve framework. The clinically useful range turns out to be 0.5-4% 10-year risk for most models.
  2. Overdiagnosis harm. The same curves can be deflated by an evidence-based overdiagnosis rate (Lindsay 2024, Glasziou 2020). The useful range shrinks visibly. This makes the overdiagnosis penalty a slider you can move, not a footnote you can skip.
  3. Regional workforce capacity. For each of Australia's 88 SA4 regions, ATOF compares the screening demand a threshold would create against the dermatologist and SCCA-accredited GP workforce that can actually deliver it. Red regions cannot deliver; green regions could deliver more.

Five workforce scenarios are available, including two modelled extensions clearly flagged as such: Total Body Photography (decouples image capture from reading) and a tiered GP-triage / specialist model.

How it works for the user

  1. Drive the controls. One slider for the risk threshold. One slider for the prevalence assumption. One slider for the overdiagnosis rate. One slider for workforce projection (0-10 years ahead). One picker for the workforce scenario. Everything updates in real time.
  2. Read the synthesised view. The headline section, “The three-component story in one frame”, puts net benefit, overdiagnosis penalty, and the regional capacity map side by side. A Play cascade button walks the threshold from 1% to 7% over five seconds so the whole argument can be presented in one motion.
  3. See the equity story. The Equity Reveal section shows the same regions stratified by SEIFA disadvantage or ARIA+ remoteness. The tool surfaces the disparity in plain numbers (847,000 Q1 residents vs 199,000 Q5 residents live in regions whose workforce cannot deliver screening at the current 3% national threshold).
  4. Export deliverables. Every chart exports as a PNG with the current configuration baked into the filename. The whole page prints to a paginated PDF with a state-stamped header banner. Every view has a sharable URL.
  5. Embed in other contexts. ATOF can be loaded inside an iframe with ?embed=1, ?embed=figure, or ?embed=map for use on a Roadmap page or a supplementary slide.

Benefits to the programme

  1. Visible trade-offs replace invisible ones. The threshold debate is currently a clinical decision with implicit assumptions about workforce. ATOF surfaces those assumptions so they can be challenged, refined, and owned by all parties.
  2. A single artefact for a multi-disciplinary conversation. Clinicians, epidemiologists, health economists, workforce planners, and equity advocates can sit in front of the same tool and see how their concerns interact in real time.
  3. Defensible scope. Every number traces to a citation; every modelled scenario is flagged as modelled; every empirical scenario cites its source. Reviewers can interrogate any value directly.
  4. Equity made operational. The tool quantifies, by SEIFA quintile and by ARIA+ remoteness, exactly which Australians a uniform threshold under-serves. Adaptive per-region thresholds become a concrete policy option rather than an abstract aspiration.
  5. Manuscript-ready outputs. PNG export, print-to-PDF, share-link, and a standalone methods page mean the same tool that drives the meeting also produces the supplementary material.

What ATOF is not

Setting expectations honestly is part of the brief:

  1. Not a microsimulation. ATOF does not track individual patients over time. The microsimulation arm is McLoughlin et al. (PLoS One 2025); the two are complementary.
  2. Not a cost-effectiveness calculator. ATOF cites MSAC 1699's ICER anchor (AUD $62,754/QALY) but does not recompute ICERs for melanoma screening.
  3. Not a clinical decision support tool. ATOF informs programme design at the population level. Individual patient decisions still belong with the clinician.
  4. Not a finished product. ATOF v0.1 is a draft for demonstration. Numbers are directional, not ready-to-cite. See the Limitations page for the complete list of assumptions and the data needed to take it from draft to v1.

In one sentence

ATOF makes the trade-off between clinical net benefit, overdiagnosis harm, and regional workforce capacity visible in one interactive view, so the national risk threshold can be chosen with eyes open to the equity consequences rather than picked on clinical grounds alone and shipped to regions that cannot deliver it.