Comparison of rectal, axillary, and forehead temperatures

Area of Science:

• Pediatric Thermometry
• Clinical Temperature Measurement

Background:

• Accurate core body temperature assessment is crucial for patient management.
• Previous studies on non-rectal thermometers have yielded conflicting results.
• Methodological differences in previous analyses may explain discrepancies.

Purpose of the Study:

• To evaluate the accuracy of axillary and forehead temperatures against rectal temperature.
• To determine reliable methods for non-invasive temperature monitoring in diverse age groups.

Main Methods:

• Prospective study involving 120 patients across six age groups.
• Calculation of paired differences and standard deviations (SDs) between axillary-rectal and forehead-rectal temperatures.
• Analysis using appropriate statistical methods (paired differences and SDs).

Main Results:

• Axillary temperature plus 1°C accurately estimated rectal temperature in patients >1 month old (mean difference 1.04°C, SD 0.45°C).
• Forehead strip thermometers showed less accuracy (mean difference 0.14°C, SD 0.60°C), with 10 readings differing by >1°C.
• In newborns, forehead thermometers were inaccurate; axillary temperature correlated with rectal temperature based on age.

Conclusions:

• Axillary temperature measurement is a safe and reliable indicator of rectal temperature in patients over 1 month when adjusted by +1°C.
• Forehead strip thermometers are less accurate than adjusted axillary measurements.
• Appropriate statistical analysis of paired differences is essential for evaluating thermometry accuracy.