Table 1.

Insulin sensitivity indices description, reported cut points for normoglycemia, and insulin resistance classification in the present study

Index	Formula	Description	Normoglycemia cut points	IR Classification and calculation in the present study
HOMA-IR	$\mathrm{FPI}\times \frac{\mathrm{FPG}}{405}$	Linear model that evaluates insulin resistance Reflects the interaction between insulin secretion and hepatic glucose production Based on fasting glucose and insulin plasma levels. [8, 9, 13]	< 2–2.5	HOMA-IR increasing values depicts insulin resistance [13] (13) HOMA-IR was not normally distributed and was logarithmically transformed implementing natural log (Ln) on the equation Upper quartile (> 1.6) of Ln HOMA-IR (Q4) was compared to the lower quartiles (< 1.6- Q1-3)
HOMA-%B	$360\times \frac{\mathrm{FPI}}{(\mathrm{FPG}-63)}$	Linear model that evaluates pancreatic beta cell function Reflects the interaction between insulin secretion and hepatic glucose production Based on fasting glucose and insulin plasma levels. [8, 9, 13]	> 100% Depend on the population [38, 39]	HOMA-%B decreasing values depicts beta cells dysfunction (13) HOMA-%B was not normally distributed and was logarithmically transformed implementing natural log (Ln) on the equation Ln HOMA-%B lower quartile (< 4.5- Q1) was compared with upper Ln HOMA-%B quartiles (> 4.5- Q2-4)
MISI	$\frac{10,000}{\sqrt{\left(\mathrm{FPG},\times ,\mathrm{FPI}\right)\times [\mathrm{mean}\mathrm{glu}\mathrm{x}\mathrm{mean}\mathrm{ins}]}}$	Evaluate the total body insulin resistance levels Based on fasting glucose and insulin plasma levels and OGTT [10]	> 4.3	MISI decreasing values depicts insulin resistance (IR) MISI mean glucose plasma levels were calculated using: fasting glucose, 60 and 120 min glucose after an oral administration of 100gr glucose. Mean insulin plasma levels were calculated using fasting insulin and insulin levels at 30, 60 and 120 min after the oral administration of 100gr glucose MISI was not normally distributed and was logarithmically transformed implementing natural log (Ln) on the equation Ln MISI lower quartile (< 0.89-Q1) was compared with upper Ln MISI quartiles (> 0.89-Q2-4)
QUICKI	$\frac{1}{\mathrm{Log}\mathrm{FPI}+\mathrm{Log}\mathrm{FPG}}$	Equivalent to the HOMA model and considered as log HOMA-IR Based on fasting glucose and insulin plasma levels Correlate better than HOMA with SI Clamp [11]	> 0.38 in non-obese	QUICKI decreasing values depicts insulin resistance. Lower quartile (< 0.3-Q1) of QUICKI was compared to upper QUICKI quartiles (> 0.3-Q2-4)
MCAi	$e^{\left[2.63,-,0.28,,\ast ,L,n,\mathrm{FPI},-,0.31,,\ast ,L,n,t,r,i,g\right]}$	Provide a simple screening tool for the assessment of insulin resistance in the population. Based on fasting insulin and triglycerides plasma levels (12)	< 5.8;  ≤ 0.63 in diabetes [44]	MCAi decreasing values depicts insulin resistance. MCAi lower quartile (< 3.2-Q1) was compared to upper MCAi quartiles (> 3.2-Q2-4)

HOMA-IR Homeostatic model assessment -Insulin resistance, FPI fasting insulin levels in $\left[\frac{\mathrm{mU}}{\mathrm{L}}\right]$, FPG fasting glucose levels in $[\frac{\mathrm{mg}}{\mathrm{dl}}]$, HOMA-%B Homeostatic model assessment—percent beta cell function (B), MISI Matsuda Insulin Sensitivity Index, Mean Glu mean glucose during OGTT, Mean Ins mean insulin during oral glucose tolerance test (OGTT); QUICKI Quantitative Insulin Sensitivity Check Index; MCAi Mcauley index, Trig, fasting triglycerides levels in $\left[\frac{\mathrm{mMole}}{\mathrm{L}}\right]$