No evidence comparing the following three methods of estimating fluid requirements is available:

1. Weight Method (Holliday-Segar Method)
2. RDA Method (Energy Method)
3. Fluid Balance Method.

In addition, there was no evidence found to establish or validate the equations. These three equations have however been cited extensively in many well respected documents and widely used in clinical practice.

Well designed studies are needed to determine and validate predictive equations to estimate fluid requirements in various populations. 

Historical background information not used in the evidence analysis on these three equations is provided in the evidence summary.

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.