What size container is most appropriate for a school-aged child to collect a 24-hour urine specimen?

The choice of a 48-ounce jar for collecting a 24-hour urine specimen is appropriate due to the volume of urine that a school-aged child is likely to produce over a full day. In general, the average urine output for children can range from about 1 to 2 ml per kg of body weight per hour, which can accumulate significantly over a 24-hour period.

For instance, if a child weighs around 20 kg, the total urine output could range from approximately 480 ml to 960 ml in a day. This amount fits well within the capacity of a 48-ounce jar (which is roughly 1.5 liters or 1500 ml), making it a suitable option for ensuring that all urine can be collected without overflow or the need for frequent transfers to a larger container.

A smaller container, such as an 8-ounce or 16-ounce jar, would likely be insufficient for collecting all the urine, resulting in the potential for lost specimens and the need for additional containers or transfers throughout the collection period. The larger 128-ounce jar would be unnecessarily large for a school-aged child, likely leading to storage and handling challenges. Therefore, the 48-ounce jar balances capacity and manageability, making it the best choice