Tested on Gulf Medical Boards (DHA, SMLE, MOH & HAAD)
Clinical calculations and diagnostic scoring systems like Insulin Sensitivity Factor (ISF) frequently appear on Prometric exams. Master high-yield clinical vignettes with instant AI-powered pathophysiology rationales.
What is the Insulin Sensitivity Factor (ISF)?
The Insulin Sensitivity Factor (ISF) is an evidence-based clinical decision rule engineered to quantify diagnostic probability, stratify clinical severity, and guide therapeutic decision-making in endocrinology & metabolism practice. The Insulin Sensitivity Factor (ISF), or Correction Factor, estimates how many milligrams per deciliter (mg/dL) the blood glucose will drop for every 1 unit of insulin administered. It is calculated using the 1800 Rule for rapid-acting insulin or the 1500 Rule for regular insulin. Clinical scoring tools like Insulin Sensitivity Factor (ISF) are essential in acute and outpatient management, enabling clinicians to objectively differentiate between low-risk candidates suitable for conservative therapy and high-risk patients requiring urgent interventions. Verified against current 2026 clinical standards, this tool is extensively tested on Gulf health authority licensing exams including DHA (Dubai), SMLE (Saudi Arabia), MOH, HAAD/DOH (Abu Dhabi), OMSB (Oman), and QCHP (Qatar).
💡Clinical Pearls & Diagnostic Utility
Provides the foundation for calculating a correction dose (bolus) when a diabetic patient has pre-meal hyperglycemia.
Formula & Calculation Parameters
The mathematical equation and clinical variables required to calculate Insulin Sensitivity Factor (ISF):
Score Interpretation & Clinical Stratification
| Score Range | Clinical Interpretation | Risk Tier |
|---|---|---|
| ≤ 150 | mg/dL drop per 1 Unit of Insulin | blue |
When to Exercise Caution
This is an empirical estimate. The actual sensitivity may vary depending on time of day, stress, illness, activity level, and injection site.
Clinical Review Board
Dr. Muhammad Nouman, MBBS
Capital Medical University | PMDC Reg No: 117744-P
Clinical Audit Status
✓ Verified for 2026 Guidelines
Last updated: 2026-08-07
Peer-Reviewed Medical Literature
- •Davidson PC, Hebblewhite HR, Steed RD, et al. Analysis of guidelines for basal-bolus insulin dosing: basal insulin, correction factor, and carbohydrate-to-insulin ratio. Endocr Pract. 2008;14(9):1095-1101.
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