What is ICOT?

The Integrated Clinical Obesity Tool (ICOT) is a clinical decision-support framework developed by Professor Steven C. Boyages MBBS FRACP FAFPHM DDU PhD (EndoHormone Institute, University of Sydney / ANU) to apply the Lancet Diabetes & Endocrinology Commission 2025 obesity framework in clinical practice.

ICOT uses a three-axis AFO profile — directly analogous to the TNM staging system in oncology — to characterise the full burden of obesity in an individual patient:

• A — Anthropometry (0–4): BMI, waist circumference, waist-to-height ratio, WHR, and fat mass index (BIS or DXA). Scores reflect the degree of excess adiposity.
• F — Functional Limitation (0–4): WHO ICF-aligned activity limitation severity, from none (0) to total dependence (4).
• O — Organ Dysfunction (0–3): Obesity-attributable organ dysfunction, KOSS-staged per domain (cardiovascular, glycaemic, renal, hepatic, respiratory, musculoskeletal, endocrine, other). The O score is the highest single domain — multiple mild conditions do not compound.

ICOT Stage formula

Stage is a maximum, not a sum. The dominant axis — the highest-scoring domain, with priority O > F > A when tied — translates directly into management direction.

Lancet Commission 2025 framework — classification

Preclinical Obesity: ≥ 2 elevated adiposity measures confirmed (A ≥1), with O ≤ 1 and F ≤ 1. Organ function preserved. Elevated future health risk.

Clinical Obesity: Confirmed excess adiposity with established obesity-related organ disease (O ≥ 2) and/or significant functional limitation (F ≥ 2). Classified as a chronic disease requiring intervention. At-risk or structural change alone (O1) remains preclinical.

AFO Diagnostic Compass

The compass renders the three-axis AFO profile as a geometric object — an equilateral triangle with A at the apex, F at bottom-left, and O at bottom-right. The patient's score triangle is plotted within concentric stage zones (Stage 0 green to Stage 4 red). The shape of the triangle reveals the dominant clinical burden and supports shared decision-making and serial monitoring.

Caveats for use

• Organ dysfunction items should only be checked when the clinician is satisfied the condition is directly attributable to excess adiposity.
• The O-axis applies the KOSS domain-staging principle: the highest single domain score determines Axis O. Multiple mild conditions do not upstage.
• Body composition values (fat mass, FMI) require validated measurement — BIS (e.g. ImpediMed SOZO) or DXA. Self-reported anthropometry should be interpreted with caution.
• Ethnicity-specific waist circumference thresholds are applied automatically based on the selected group; review IDF/WHO guidance if in doubt.
• The calculator does not store, transmit, or retain any patient data. All computation occurs locally in your browser.
• Prospective validation of the AFO/ICOT framework in diverse clinical cohorts is ongoing. Independent validation is invited.

Ownership & intellectual property

The ICOT AFO framework, AFO notation, ICOT staging system, and AFO Diagnostic Compass are the intellectual property of Professor Steven C. Boyages MBBS FRACP FAFPHM DDU PhD, EndoHormone Institute Pty Ltd, Sydney, Australia. © 2026. All rights reserved.

This tool is provided freely for clinical use and education. Reproduction, adaptation, or commercial use without written permission is not permitted.

References

This tool is based on the Lancet Commission 2025 framework for defining and diagnosing obesity:

• Rubino F, Cummings DE, Eckel RH, et al. Definition and diagnostic criteria of clinical obesity. Lancet Diabetes Endocrinol. 2025;13(3):221–262. doi:10.1016/S2213-8587(24)00316-4 [Lancet Commission 2025 — primary framework reference]
• Ko TYL, Miras AD, Pournaras DJ, Le Roux CW. Beyond BMI: practical guide for clinicians to integrate the Lancet Commission's obesity framework and King's Obesity Staging System. Clin Obes. 2026;16(1):e70045. doi:10.1111/cob.70045
• Padwal RS, Pajewski NM, Allison DB, Sharma AM. Using the Edmonton obesity staging system to predict mortality in a population-representative cohort of people with overweight and obesity. CMAJ. 2011;183(14):E1059–E1066. doi:10.1503/cmaj.110387
• Sharma AM, Kushner RF. A proposed clinical staging system for obesity. Int J Obes. 2009;33(3):289–295.

Version history

v4.6 — 11 October 2026. Corrections to match the published AFO criteria and the Lancet Commission definition; the stage formula is unchanged.

• Clinical obesity now requires established organ disease (O ≥2) or significant functional limitation (F ≥2) with confirmed adiposity. In v4.5 any ticked organ item, including at-risk O1 findings, triggered "clinical".
• A ≥1 requires confirmed excess adiposity (≥2 elevated measures, or elevated fat mass index). The v4.5 +1 upgrade when all measures were elevated has been removed.
• Adults without confirmed adiposity are not staged; A0 F0 O0 is Stage 0 (healthy weight).
• Stage descriptions and management text follow the Lancet status read from the AFO profile, so Stage 2 is no longer always labelled "preclinical".
• BMI ≥27.5 kg/m² without a second measure is reported as "A unclassifiable" rather than A0.
• The embedded staging guide no longer shows the withdrawn NHANES v2.3 results.
• Stable angina / chronic coronary syndrome and atrial fibrillation / flutter rescored from O1 to O2 (established disease), so either now meets the clinical-obesity criterion.
• Header restyled: white text on dark blue.

v4.5 — 9 October 2026. Stage formula max(F, O, min(A, 2)); updated references.

Feedback & collaboration

Clinical feedback, validation enquiries, and collaboration proposals are welcome. Please contact: steven.boyages@sydney.edu.au