Related Experiment Video

Updated: Nov 21, 2025

Low-Cost, Volume-Controlled Dipstick Urinalysis for Home-Testing
06:55

Low-Cost, Volume-Controlled Dipstick Urinalysis for Home-Testing

Published on: May 8, 2021

6.0K

Combining urine color and void number to assess hydration in adults and children

J D Adams1, Giannis Arnaoutis2, Evan C Johnson3

  • 1Department of Health and Human Performance, College of Charleston, Charleston, SC, USA.

European Journal of Clinical Nutrition
|January 19, 2021
PubMed

Insights

This study shows that urine color and voiding frequency are effective indicators of underhydration in adults and children. Combining these simple measures accurately detects elevated urine osmolality, aiding in hydration status assessment.

Area of Science:

  • Clinical diagnostics
  • Human physiology
  • Urine analysis

Background:

  • Underhydration, indicated by elevated urine osmolality (UOsm), is a common concern in free-living individuals.
  • Accurate and simple methods for detecting underhydration are needed for both adults and children.

Purpose of the Study:

  • To evaluate the diagnostic accuracy of two practical, combined markers for detecting elevated urine osmolality (underhydration).
  • To assess the utility of urine color (UC) and voiding frequency (void) as indicators of hydration status.

Main Methods:

  • 101 adults and 210 children provided 24-hour urine samples for analysis of urine osmolality (UOsm) and urine color (UC).
  • Voiding frequency (void) was recorded, and Receiver Operating Characteristic (ROC) analysis was used to determine diagnostic ability for underhydration (UOsm ≥ 800 mmol kg⁻¹).

Main Results:

  • Both UC and void were significantly associated with UOsm in adults and children.
  • In adults, the combination of UC > 3 and void < 7 achieved 97% diagnostic ability for underhydration (100% sensitivity, 88% specificity).
  • In children, UC > 3 and void < 5 achieved 89% diagnostic ability (100% sensitivity, 62% specificity).

Conclusions:

  • Urine color and voiding frequency serve as valid and simple field measures for detecting underhydration.
  • The combination of these markers provides a practical approach to identifying elevated urine osmolality in diverse populations.
Abstract

More Related Videos

Real-Time Void Spot Assay06:39

Real-Time Void Spot Assay

Published on: February 10, 2023

2.4K
Assessing Urinary Tract Junction Obstruction Defects by Methylene Blue Dye Injection06:05

Assessing Urinary Tract Junction Obstruction Defects by Methylene Blue Dye Injection

Published on: October 12, 2017

16.0K

Related Concept Videos

Urine Studies I: Urinalysis01:29

Urine Studies I: Urinalysis

Urinalysis is a widely used diagnostic test that analyzes urine's physical, chemical, and microscopic characteristics. Healthcare providers use it to detect and monitor various health conditions, including renal disease, urinary tract infections (UTIs), diabetes, and metabolic or systemic disorders.Components of UrinalysisUrinalysis consists of three primary components: physical, chemical, and microscopic examination. Each provides unique insights into the urine sample and, by extension, the...
628
Urodynamic Studies: Uroflowmetry01:19

Urodynamic Studies: Uroflowmetry

Uroflowmetry is a non-invasive urodynamic test designed to measure various aspects of urination, including volume, flow rate, and the time to void. This test is crucial for diagnosing and assessing conditions such as bladder outlet obstruction, bladder dysfunction, incomplete bladder emptying, incontinence, and urinary tract blockages caused by benign prostatic hyperplasia (BPH) and urethral strictures.Pre-Test Instructions:Before a uroflowmetry test, patients are typically advised to drink...
1.6K
Physiology of the Genitourinary System III: Urine Concentration and Dilution01:20

Physiology of the Genitourinary System III: Urine Concentration and Dilution

The kidneys concentrate or dilute urine to maintain water and electrolyte balance. Nephrons, particularly the loop of Henle, play a crucial role in this process through the countercurrent multiplication system. This system establishes a high osmolarity in the renal medulla, which is essential for water reabsorption. In the loop of Henle’s descending limb, water is reabsorbed into the surrounding medulla due to its permeability to water. In contrast, the ascending limb actively transports...
283
Urine: Physical and Chemical Properties01:18

Urine: Physical and Chemical Properties

Urine comprises approximately 95% water and 5% solutes. The primary ingredient, apart from water, is urea - a byproduct of the breakdown of amino acids. Other notable components include uric acid, a residue from nucleic acid metabolism, and creatinine, a metabolite from creatine phosphate breakdown in skeletal muscle tissue.
The concentration of these solutes varies, with urea being the most abundant nitrogenous waste product. Other solutes include sodium, chloride, potassium, phosphate,...
2.6K
Serum Studies: Renal Function Tests01:24

Serum Studies: Renal Function Tests

Renal function tests are crucial for assessing kidney health, monitoring disease progression, and evaluating the kidneys' efficiency in waste elimination, fluid balance, and electrolyte regulation. These tests offer critical insights into kidney function, even though routine measurements may appear normal until there is a significant decline in the glomerular filtration rate or GFR. Typically, signs of kidney impairment only become evident when the GFR falls to about 50% of its normal level.
188
Imaging Studies VI: Voiding Cystourethrography and Cystography01:22

Imaging Studies VI: Voiding Cystourethrography and Cystography

Voiding Cystourethrography (VCUG) and Cystography are specialized radiographic procedures used to examine the structure and function of the bladder and urethra.Voiding Cystourethrography (VCUG)A Voiding Cystourethrogram (VCUG) is a diagnostic imaging procedure that assesses the anatomy and function of the lower urinary tract. It focuses on the bladder, bladder neck, and urethra, helping detect abnormalities such as vesicoureteral reflux (VUR)—the backward or reverse flow of urine into the...
486