Cock.Rmd

---
title: "Cockcroft"
author: "kou"
date: "12/26/2017"
output: html_document
---

## Cockcroft-Gault formula

<details><summary>Why is creatinine clearance important?</summary>Creatinine is metabolic products from muscle. Creatinine is not reabsorbd and only few creatinine is secreted at renal tube.  
So, creatinint clearance (CCr) resembles in glomerular filtration rate (GFR).  
CCr was calculated by this formula from urine test.  
$$
CCr(ml/min) = \frac{Ucr(mg/dL) \times UV(mL/day)}{Scr(mg/dL)\times 1440(min/day)}* \frac{1.73}{BSA(m^2)}\\
\\
Ucr: urine creatinine, Scr: serum creatinine, UV: urine volume, BSA: body surface area
$$
</details>


<details><summary>Why is these formula made?</summary>To determine creatinine clearance, urine test is need. But urine test is time-consuming...  
Many doctors want to determine creatinine clearance only from serum creatinine.  
</details>

***

 In 1973, ***Cockcroft-Gault*** formula are proposed.  
This formula is estimated by 249 participants. (The range of their creatinine is 30 - 130 mL/min)  

* Cockcroft-Gault formula  
    * male
$$
CCr_{(male)}   = \frac{(140 - Age)\times BW}{72\times Scr}
$$
    * female
$$
CCr_{(female)} = \frac{(140 - Age)\times BW}{72\times Scr}\times 0.85
$$


* This is reference of Cockcroft-Gault (NCBI)

[Cockcroft, D.W. and M.H. Gault. Prediction of creatinine clearance from serum creatinine. Nephron. 1976. 16(1):31-41.](https://www.ncbi.nlm.nih.gov/pubmed/1244564)