Clinical Dehydration Scale (CDS) Calculator for Children

The CDS organizes four observed findings into a 0–8 observational scale for children with acute gastroenteritis. It is an adjunct to a complete assessment, not a universal dehydration diagnosis or an exact measurement of fluid loss.

Sources: [1, 6]

General appearance, eyes, mucous membranes (tongue), and tears are each scored 0, 1, or 2 and added for a total of 0–8. Pulse, capillary refill, urine output, breathing, skin turgor, and blood pressure remain clinically important but are not CDS arithmetic items.

Sources: [1]

The CDS was developed in children 1–36 months with acute gastroenteritis, and later validation included children from 1 month through 5 years. This calculator does not diagnose gastroenteritis; use outside the studied population requires a different clinical assessment.

Sources: [1, 2, 3]

The formal categories are score 0, ‘No dehydration detected by the scale’; scores 1–4, ‘Some dehydration’; and scores 5–8, ‘Moderate/severe dehydration.’ They are research categories and do not replace a full assessment.

Sources: [2, 3]

No. Historical bands of <3%, 3% to <6%, and ≥6% are study-category context, not an individual measured deficit. They must not be multiplied by body weight to calculate a rehydration volume.

Sources: [2, 3]

No. A score of 0 means that dehydration was not detected by these four scale items. It cannot rule out clinically important dehydration, shock, deterioration, or another serious diagnosis.

Sources: [6]

A systematic review found limited rule-in value for ≥6% dehydration in some high-income settings, but the CDS could not reliably rule dehydration out. Accuracy was limited for lower percentage categories and in other settings, so clinical judgment remains essential.

Sources: [6]

Change between a reliable pre-illness or admission weight and a completed post-rehydration weight is a commonly used research reference. In practice the earlier weight may be unreliable and the later weight incomplete or affected by continuing losses.

Sources: [10]

Shock, altered consciousness, deterioration, reduced urine output, abnormal heart rate or breathing, weak pulses, prolonged capillary refill, hypotension, poor skin turgor, inability to drink, bilious vomiting, bloody stool, severe abdominal pain, sepsis, and neurological or respiratory illness require assessment independent of the CDS total.

Sources: [7, 10]

No. It does not select oral rehydration solution, nasogastric or intravenous routes, volume, rate, monitoring, or another treatment. Those decisions require complete assessment and the applicable local guideline.

Sources: [4, 7, 9]

The original CDS evidence does not establish this calculator for neonates, children older than 5 years, adults, or illnesses outside the acute-gastroenteritis context. Those situations require a different clinical assessment rather than an age or context gate inside the four-item score.

Sources: [1, 2, 3]

No. The score cannot determine safe home observation, laboratory testing, referral, admission, or discharge. Red flags, shock, severe disease, alternative diagnoses, losses, intake, examination findings, and local pathways take priority.

Sources: [7, 9, 10]