Final answer:
An acceptable rectal temperature in children is typically 36.5-37.5 °C (97.7-99.5 °F). A temperature >37.5 or 38.3 °C (99.5 or 100.9 °F) is generally considered a fever. Accurate measurement with a reliable thermometer is critical to properly assess the child's health status.
Step-by-step explanation:
An acceptable rectal temperature in children varies slightly from the average adult body temperature. While the setpoint for human body temperature is around 37 °C (98.6 °F), the normal range for a child's body temperature is approximately 36.5-37.5 °C (97.7-99.5 °F). Considering the natural fluctuations around the setpoint, slight deviations within this range can be normal and not necessarily indicative of a fever or illness.
In clinical terms, a child is considered to have a fever if the rectal temperature is >37.5 or 38.3 °C (99.5 or 100.9 °F). It is important to use a thermometer with low uncertainty to ensure accurate measurement, as a large uncertainty could lead to misinterpretation of the child's health status. If the thermometer's uncertainty is too high, such as 3.0°C, it could render the measurement unreliable, potentially masking a fever or suggesting one where there is none.