Final answer:
The Lund and Browder method is the most accurate for assessing the total body surface area affected by burns in young children, as it accounts for changes in body proportion with age.
Step-by-step explanation:
The most accurate method of assessing the total body surface area affected by a burn in a young child is through the use of the Lund and Browder method.
Unlike the Rule of Nines, which is more suitable for adults and provides an estimation by associating specific anatomical areas with a percentage that is a factor of nine, the Lund and Browder method takes into account the changes in body proportion with age and provides a more detailed assessment which is particularly important in pediatric patients.
The Hand Method is considered a quick estimate, using the size of the patient's hand to represent approximately 1% of their total body surface area.
The Parkland Formula is not a tool for measuring the burn size but rather for calculating fluid resuscitation requirements after a burn.