Temperature measured at the axilla compared with rectum in children and young people: systematic review

Abstract

Objective To evaluate the agreement between temperature measured at the axilla and rectum in children and young people. Design A systematic review of studies comparing temperature measured at the axilla (test site) with temperature measured at the rectum (reference site) using the same type of measuring device at both sites in each patient. Devices were mercury or electronic thermometers or indwelling thermocouple probes. Studies reviewed 40 studies including 5528 children and young people from birth to 18 years. Data extraction Difference in temperature readings at the axilla and rectum. Results 20 studies (n = 3201 (58%) participants) had sufficient data to be included in a meta-analysis. There was significant residual heterogeneity in both mean differences and sample standard deviations within the groups using different devices and within age groups. The pooled (random effects) mean temperature difference (rectal minus axillary temperature) for mercury thermometers was 0.25°C (95% limits of agreement − 0.15°C to 0.65°C) and for electronic thermometers was 0.85°C ( − 0.19°C to 1.90°C). The pooled (random effects) mean temperature difference (rectal minus axillary temperature) for neonates was 0.17°C ( − 0.15°C to 0.50°C) and for older children and young people was 0.92°C ( − 0.15°C to 1.98°C). Conclusions The difference between temperature readings at the axilla and rectum using either mercury or electronic thermometers showed wide variation across studies. This has implications for clinical situations where temperature needs to be measured with precision.

A Randomized Trial of Exothermic Mattresses for Preterm Newborns in Polyethylene Bags

“…Although correlation between rectal and axillary temperature in preterm infants is poorly studied, axillary temperature is considered to be less than rectal temperature by up to 0.5°C. 18 For this reason, studies reporting axillary temperature may have overestimated the occurrence of hypothermia. In this trial, mean rectal temperature was 0.1°C higher than axillary temperature.…”

Heart Rates in Hospitalized Children by Age and Body Temperature

“…We expected the HR for observations with noncore body temperatures to be higher because of the potential for axillary temperatures, the most common form of noncore temperature measurement, to underestimate true body temperature. 16 …”

“…Other temperature measurement methods have variable degrees of error when compared with core temperatures, and we were concerned that including these observations could lead to less accurate and precise percentiles. 16,17 The most common method of temperature measurement for young children in our sample was axillary, a method that, on average, underestimates body temperature. 16 For each observation we determined HR z scores by age (HRZ age ) using a reference for expected HR in hospitalized children previously developed by our team.…”

“…16,17 The most common method of temperature measurement for young children in our sample was axillary, a method that, on average, underestimates body temperature. 16 For each observation we determined HR z scores by age (HRZ age ) using a reference for expected HR in hospitalized children previously developed by our team. 18 We divided data at the patient level into derivation (60%) and validation (40%) data sets after using bootstrapped samples to determine the minimum sample size that would produce stable estimates of outer percentiles.…”

Surveillance for ocular hypertension: an evidence synthesis and economic evaluation

“…117 Each item was graded as 'yes' , 'no' , or 'unclear' . The quality assessment of diagnostic accuracy studies (QUADAS) tool 116 is a recently developed quality assessment tool for use in systematic reviews of diagnostic accuracy studies; however, for this review it was adapted to make it applicable to assessing the quality of reliability and agreement studies.…”