Reliability of noncontact infrared thermometry for temperature measurement in newborns: A prospective and observational study

Introduction: Accurate temperature measurement is critical for neonatal care. Traditional methods such as digital axillary thermometry (DAT) are reliable but invasive, posing risks of discomfort and infection. Noncontact infrared thermometers (NCIT) offer a noninvasive alternative, but their reliability compared to DAT in newborns remains under scrutiny. Objectives: To assess the reliability and agreement of NCIT compared to DAT for temperature measurement in newborns, and to determine the most reliable anatomical site for NCIT readings. Methodology: This prospective study was conducted in the postnatal wards of Father Muller Medical College Hospital, Mangalore, from July to August 2024. Sixty-three neonates were included, with 744 temperature readings taken at the axilla (using DAT) and three NCIT sites: Forehead, sternum, and interscapular region. Data were analyzed using Pearson correlation and Bland–Altman methods to assess agreement between methods. Intraclass correlation was used to identify the best NCIT site. Results: The mean axillary temperature was 98.2°F, while NCIT readings averaged 98.1°F (forehead), 99.5°F (sternum), and 99.9°F (interscapular). Intraclass correlation revealed the forehead as the most reliable NCIT site (intraclass correlation coefficient = 0.655) compared to the axilla. Strong agreement was noted in neonates of all gestational ages (≥37 weeks) and birth weights, with better results for term neonates and low-birth-weight (LBW) infants. NCIT readings over the forehead showed minimal mean difference (−0.15°F) compared to axillary readings. Conclusion: NCIT at the forehead demonstrated good reliability and clinical reproducibility, making it a viable alternative to DAT for routine temperature monitoring in healthy term and LBW neonates. Its nonintrusiveness and reduced risk of infection make it suitable for neonatal care.