Non-contact Infrared Thermometers Research Articles

Assessment of preferable site for temperature measurement using non-contact infra-red temperature among pediatric patients.

Accurate temperature measurement with little or no discomfort that is safe, without risk of hospital-acquired infections or perforations, is the preferred choice of medical professionals in pediatric settings. The objective was to discover the preferable site for body temperature measurement using non-contact infra-red thermometer (NCIT) among pediatric patients. NCIT measurement at mid forehead (F), right temporal region (T), right side of neck-over-carotid artery area (N), jugular notch (J), sternum (S), umbilical region and sublingual region (U) were compared with digital axillary temperature (DAT) in a single attempt in 500 patients, aged between 2 to 5 years with fever. Data was analyzed using Pearson's correlation, paired t-test and Bland-Altman plot to assess the correlation and agreement between the DAT and NCIT sites. The mean temperature of NCIT-T (38.42±0.64 °C) was more agreeable with DAT (38.42±0.63 °C) compared to other body sites. The minimum mean bias of -0.00480 °C was noted for NCIT-F with 95% CI of -0.164-0.15; however, NCIT-F revealed many outliers as compared to NCIT-J. A strong positive correlation existed between DAT and NCIT sites (r value: 0.99-0.98). However, significant difference was found between DAT and NCIT-N, NCIT-F and NCIT-U (P<0.0001). NCIT-J is the most preferable choice for measuring body temperature and can be interchanged with DAT. It will help to deliver fast results with enhanced patient comfort due to its non-invasive nature.

Evaluation of Non-Contact Device to Measure Body Temperature in Sheep.

Non-contact devices have been used in the measurement of body temperature in livestock production as a tool for testing disease in different species. However, there are few studies about the variation and correlations in body temperature between rectal temperature (RT) and non-contact devices such as non-contact infrared thermometers (NCIT) and thermal imaging/infrared thermography (IRT). The objective of this work was to evaluate the accuracy of non-contact devices to measure the body temperature in sheep, considering six body regions and the possibility of implementing these systems in herd management. The experiment was carried out at the experimental farm of the Catholic University of Valencia, located in the municipality of Massanassa in July of 2021, with 72 dry manchega ewes, and we compared the rectal temperature with two types of non-contact infrared devices for the assessment of body temperature in healthy sheep. Except for the temperature taken by NCIT at the muzzle, the correlation between RT vs. NCIT or IRT showed a low significance or was difficult to use for practical flock management purposes. In addition, the variability between devices was high, which implies that measurements should be interpreted with caution in warm climates and open pens, such as most sheep farms in the Spanish Mediterranean area. The use of infrared cameras devices to assess body temperature may have a promising future, but in order to be widely applied as a routine management method on farms, the system needs to become cheaper, simpler in terms of measurements and quicker in terms of analyzing results.

Development of an IoT Embedded Wearable Device with Non-Contact Temperature Detector for Early Detection of Fever

One of the most common and early symptoms of any viral infections is fever which is the reaction to a disease-specific stimulus causing the increase of human body temperature. The current common method of monitoring the human body temperature uses the application of non-contact infrared thermometer (NCIT) and is only limited for stationary conditions within short distances and mostly suitable for indoor premises. The available technology to detect human body temperature for longer distances uses the thermal camera which is costly and large. Thus, it is challenging to detect anyone with high body temperature innon-stationary conditions, at longer distances, especially outdoor. The paper proposes an innovation to the current practice, for a wearable non-contact temperature detector device which is portable. The wearable non-contact temperature detector embeds a thermal sensor and a microcontroller to a normal hat. It is able to detect objects with higher temperature (37.5 C)within 1 meter radius of 60° angle viewin stationary and non-stationary conditions. The wearable device communicates via Bluetooth to a mobile device to display the detected temperature and notifies the user via alert message and alarm for high temperature detection. Display of the object’s thermal image is also available with a resolution of 8 8 pixel. The wearable non-contact temperature detector is able to achieve 99% accuracy of temperature measurement for detection distance of up to 70 cm for indoor and within 20 cm for outdoor when tested with normal temperature subject and high temperature objectsand compared with the actual temperature detected via a commercial NCIT device.

Temperature Monitoring in Children: An Agreement Study

Background: Noncontact infrared thermometer (NCIT) measures temperature rapidly and noninvasively. It is commonly used at forehead, but other potential sites such as axilla and abdomen are yet to be explored. We assessed agreement of temperature recordings of axillary temperature by glass mercury thermometer (the “gold standard”) with axillary temperature by the digital thermometer as well as with NCIT at forehead, axilla, mid abdomen, and at right hypochondriac areas. Methods: Neonates and children below 5 years admitted in neonatal and pediatrics wards were enrolled in the study through convenience sampling. For each participant, temperature was measured using NCIT at forehead, mid abdomen, right hypochondrium, and right axilla as well as using digital thermometer at right axilla and using glass mercury thermometer at right axilla. The agreement between methods was presented as mean difference (95% limits of agreement) using Bland-Altman analysis. Results: Total 400 temperature readings were taken for each method from 132 participants. There was a good agreement between mercury axillary with digital axillary in both the groups, that is, neonates and children (&gt;1 month to 5 years) (Mean difference [95% limits of agreement] = –0.046 [–0.26 to 0.169]°C and –0.028 [–0.183 to 0.128]°C, respectively). While for all the methods using NCIT, there was a poor agreement with mercury axillary temperature in both the groups. Conclusion: Agreement between axillary temperatures using digital and glass mercury thermometers was good, while agreements between the axillary temperature using glass mercury thermometer with NCIT readings at different sites were poor in neonates and children below 5 years.

Agreement of Temperatures Measured Using a Non-Contact Infrared Thermometer With a Rectal Digital Thermometer in Horses.

Evaluating the body temperature of horses is an essential tool for monitoring horse health and biosecurity in groups of horses. Temperatures of horses and foals are determined most often using rectal thermometry. Rectal thermometry has limitations that include safety considerations for horses and humans. Thus, we investigated the agreement between a noncontact infrared thermometer (NCIT) and a rectal digital thermometer in 142 horses and 34 foals. For each horse and foal, measurements using the NCIT were collected from the forehead (n=2) or neck (n=1) and with a rectal digital thermometer (n=1). Although the NCIT demonstrated good reliability (i.e. repeatability of measurements), a large negative bias (nearly 2°F (-16.7°C) in adult horses and >3°F (-16.1°C) in foals) was observed between readings from the NCIT and the rectal thermometer in healthy horses. Although horses with febrile illness were not included in the study, our results indicate that the large and inconsistent bias observed with the NCIT indicates that these devices will not be a suitable substitute for rectal thermometry for obtaining valid estimates of core body temperature in horses.

Optimal diagnostic fever thresholds using non-contact infrared thermometers under COVID-19.

Fever screening is an effective method to detect infectors associated with different variants of coronavirus disease 2019 (COVID-19) based on the fact that most infectors with COVID-19 have fever symptoms. Non-contact infrared thermometers (NCITs) are widely used in fever screening. Nevertheless, authoritative data is lacking in defining "fever" at different body surface sites when using NCITs. The purpose of this study was to determine the optimal diagnostic threshold for fever screening using NICTs at different body surface sites, to improve the accuracy of fever screening and provide theoretical reference for healthcare policy. Participants (n = 1860) who were outpatients or emergency patients at Chengdu Women's and Children's Central Hospital were recruited for this prospective investigation from March 1 to June 30, 2021. NCITs and mercury axillary thermometers were used to measure neck, temple, forehead and wrist temperatures of all participants. Receiver operating characteristic curves were used to reflect the accuracy of NCITs. Linear correlation analysis was used to show the effect of age on body temperature. Multilinear regression analysis was used to explore the association between non-febrile participant's covariates and neck temperature. The mean age of participants was 3.45 ± 2.85 years for children and 28.56 ± 7.25 years for adults. In addition 1,304 (70.1%) participants were children (≤12), and 683 (36.7%) were male. The neck temperature exhibited the highest accuracy among the four sites. Further the optimal fever diagnostic thresholds of NCITs at the four body surface measurement sites were neck (36.75 °C, sensitivity: 0.993, specificity: 0.858); temple (36.55 °C, sensitivity: 0.974, specificity: 0.874); forehead (36.45 °C, sensitivity: 0.961, specificity: 0.813); and wrist (36.15 °C, sensitivity: 0.951, specificity: 0.434). Based on the findings of our study, we recommend 36.15, 36.45, 36.55, and 36.75 °C as the diagnostic thresholds of fever at the wrist, forehead, temple and neck, respectively. Among the four surface sites, neck temperature exhibited the highest accuracy.

Technologies for Fever Screening in the Time of COVID-19: A Review

During the COVID-19 pandemic, there has been an increasing rollout of non-contact fever screening solutions to assist in curbing the spread of disease. This study begins by describing how screening for disease has historically been performed. It proposes four measurement characteristics of an ideal screening solution: non-contact, effective, rapid and low-cost measurements. Next, it reviews the existing literature on fever-screening using non-contact infrared thermometer (NCIT) devices as well as infrared thermography (IRT) devices, as these are two technologies which have experienced increasing use. For this review, 185 research papers were identified, 21 research studies were included after inclusion and exclusion criteria were applied. A total of 35 experiments were identified for analysis and their results tabulated. Of these studies, 66% are IRT and 34% are NCIT, with a median sample size of 430 subjects. 26 experiments involve febrile participants, with a median febrile percentage of 11.22 % of population. The reported sensitivity of febrile detection using NCIT varies from 3.7% to 97% and when using IRT it varies from 15% to 100%. Both indoor and outdoor studies are investigated, as well as those conducted in acute and non-acute settings. The results of this review show a clear lack of consensus on the effectiveness of these systems. Overall, these results indicate that sensitivity and specificity are reduced when using IRT and NCIT technologies compared to other thermometers used in medical practice. Their use should be carefully assessed based on the risks present in each particular measurement scenario.

A noninvasive method of temperature measurement using a noncontact handheld infrared thermometer fails to correlate with rectal temperature in dogs and cats.

To perform a retrospective, multicenter observational study that compares the agreement of rectal temperature with the temperature measured with noncontact infrared thermometer (NCIT) in a population of dogs and cats. 168 dogs and 61 cats. NCIT readings were taken in triplicate from the medial pinna, then rectal temperature was taken with a standard digital rectal thermometer (RT). Ambient room temperature, signalment, presence of icterus, skin and coat color, reason for presentation, and final diagnosis were recorded. In dogs, median (range) body temperature reflected by RT and NCIT measurements was 38.4 °C (33.4 to 40.3 °C) and 36.3 °C (30.8 to 40.0 °C), respectively. In cats, median (range) body temperature reflected by RT and NCIT measurements was 38.3 °C (36.2 to 40.0 °C) and 35.7 °C (31.8 to 38.0 °C), respectively. There was a weak positive correlation between body temperatures measured by NCIT and RT in dogs (Kendall tau = 0.154), but there was no correlation in cats (Kendall tau = -0.01). A significant, albeit weak, agreement was seen between temperature measured by NCIT and RT in dogs (Kappa value, 0.05), but not cats (Kappa value, -0.08). In both species, NCIT tended to underread body temperature, compared with RT (dogs: mean ± SD bias -2.2 ± 1.51 °C; cats: mean bias -2.7 ± 1.44 °C), with the degree of low measurements lessening as body temperature increased. Given both poor correlation and agreement in body temperature measured by NCIT and rectal thermometer, NCIT measurements cannot be recommended at the current time as a means to determine body temperature in dogs and cats.

Reliability of Non-Contact Infrared Thermometers for Fever Screening Under COVID-19.

PurposeFever is one of the most typical clinical symptoms of coronavirus disease 2019 (COVID-19), and non-contact infrared thermometers (NCITs) are commonly used to screen for fever. However, there is a lack of authoritative data to define a “fever” when an NCIT is used and previous studies have shown that NCIT readings fluctuate widely depending on ambient temperatures and the body surface site screened. The aim of this study was to establish cut-off points for normal temperatures of different body sites (neck, forehead, temples, and wrist) and investigate the accuracy of NCITs at various ambient temperatures to improve the standardization and accuracy of fever screening.Patients and MethodsA prospective investigation was conducted among 904 participants in the outpatient and emergency departments of Chengdu Women’s and Children’s Central Hospital. Body temperature was measured using NCITs and mercury axillary thermometers. A receiver operating characteristic curve was used to determine the accuracy of body temperature detection at the four body surface sites. Data on participant characteristics were also collected.ResultsAmong the four surface sites, the neck temperature detection group had the highest accuracy. When the neck temperature was 37.35°C as the optimum fever diagnostic threshold, the sensitivity was 0.866. The optimum fever diagnostic thresholds for forehead, temporal, and wrist temperature were 36.65°C, 36.65°C, and 36.75°C, respectively. Moreover, triple neck temperature detection had the highest sensitivity, up to 0.998, whereas the sensitivity of triple wrist temperature detections was 0.949. Notably, the accuracy of NCITs significantly reduced when the temperature was lower than 18°C.ConclusionNeck temperature had the highest accuracy among the four NCIT temperature measurement sites, with an optimum fever diagnostic threshold of 37.35°C. Considering the findings reported in our study, we recommend triple neck temperature detection with NCITs as the fever screening standard for COVID-19.

Infrared Thermography for Measuring Elevated Body Temperature: Clinical Accuracy, Calibration, and Evaluation.

Infrared thermographs (IRTs) implemented according to standardized best practices have shown strong potential for detecting elevated body temperatures (EBT), which may be useful in clinical settings and during infectious disease epidemics. However, optimal IRT calibration methods have not been established and the clinical performance of these devices relative to the more common non-contact infrared thermometers (NCITs) remains unclear. In addition to confirming the findings of our preliminary analysis of clinical study results, the primary intent of this study was to compare methods for IRT calibration and identify best practices for assessing the performance of IRTs intended to detect EBT. A key secondary aim was to compare IRT clinical accuracy to that of NCITs. We performed a clinical thermographic imaging study of more than 1000 subjects, acquiring temperature data from several facial locations that, along with reference oral temperatures, were used to calibrate two IRT systems based on seven different regression methods. Oral temperatures imputed from facial data were used to evaluate IRT clinical accuracy based on metrics such as clinical bias (), repeatability, root-mean-square difference, and sensitivity/specificity. We proposed several calibration approaches designed to account for the non-uniform data density across the temperature range and a constant offset approach tended to show better ability to detect EBT. As in our prior study, inner canthi or full-face maximum temperatures provided the highest clinical accuracy. With an optimal calibration approach, these methods achieved a between ±0.03 °C with standard deviation () less than 0.3 °C, and sensitivity/specificity between 84% and 94%. Results of forehead-center measurements with NCITs or IRTs indicated reduced performance. An analysis of the complete clinical data set confirms the essential findings of our preliminary evaluation, with minor differences. Our findings provide novel insights into methods and metrics for the clinical accuracy assessment of IRTs. Furthermore, our results indicate that calibration approaches providing the highest clinical accuracy in the 37–38.5 °C range may be most effective for measuring EBT. While device performance depends on many factors, IRTs can provide superior performance to NCITs.

Clinical evaluation of non-contact infrared thermometers

Non-contact infrared thermometers (NCITs) are being widely used during the COVID-19 pandemic as a temperature-measurement tool for screening and isolating patients in healthcare settings, travelers at ports of entry, and the general public. To understand the accuracy of NCITs, a clinical study was conducted with 1113 adult subjects using six different commercially available NCIT models. A total of 60 NCITs were tested with 10 units for each model. The NCIT-measured temperature was compared with the oral temperature obtained using a reference oral thermometer. The mean difference between the reference thermometer and NCIT measurement (clinical bias) was different for each NCIT model. The clinical bias ranged from just under − 0.9 °C (under-reporting) to just over 0.2 °C (over-reporting). The individual differences ranged from − 3 to + 2 °C in extreme cases, with the majority of the differences between − 2 and + 1 °C. Depending upon the NCIT model, 48% to 88% of the individual temperature measurements were outside the labeled accuracy stated by the manufacturers. The sensitivity of the NCIT models for detecting subject’s temperature above 38 °C ranged from 0 to 0.69. Overall, our results indicate that some NCIT devices may not be consistently accurate enough to determine if subject’s temperature exceeds a specific threshold of 38 °C. Model-to-model variability and individual model accuracy in the displayed temperature were found to be outside of acceptable limits. Accuracy and credibility of the NCITs should be thoroughly evaluated before using them as an effective screening tool.

Modeling digital terrestrial television signal strength with atmospheric parameters and noise temperature: a case study of North-Central Nigeria

The modeling of DTTV signal strength (AIT, NTA, ETV and Channels TV) in Abuja and Unity TV, Jos, Plateau State, with atmospheric parameters (temperature, pressure, relative humidity, wind speed and rainfall) as well as noise temperature, from April 2019 to December 2020 have been carried out using the atmospheric parameters measured with an automatic weather station and noise temperature measured with a non-contact infra-red thermometer, with TV signal strength measured with a CATV signal strength meter from 5.00 am – 9.00 pm daily, at 30 minutes interval. The results show that atmospheric temperature (58%), noise temperature (60%) and atmospheric pressure (100%) affect the Received Signal Strength (RSS) negatively, while the wind speed (60%), relative humidity (80%), and rainfall (100%) affect the signal strength positively. The RSS measured in Jos on altitude 1,400m was higher than that in Abuja on altitude 470m which may likely be due to an increase in altitude resulting in a decrease in atmospheric pressure and air density which implies less signal attenuation. It can be inferred that atmospheric parameters and noise temperature have a great impact on the RSS in the study areas. Consequently, the higher signal received in the rainy season compared to the dry season may be due to less dust in the atmosphere as well as the enhanced digitalized television signal and its robustness to interference and signal attenuation compared to the analogue signal. The developed models have low RMSE values; hence will be able to predict the influence of atmospheric parameters on TV RSS in the areas. Generally, the result will be useful to the Nigeria Broadcasting Commission to improve the quality of the signal transmission of digital television broadcasting for the future digital switchover in other parts of the country especially on the choice of antennas on their transmitters. The findings will also be useful to spectrum users such as mobile telecommunication, wireless internet, and radio broadcasting in managing and improving the quality of their services.

Real-World Evidence: The Low Validity of Temperature Screening for COVID-19 Triage.

Background: The COVID-19 pandemic forced health-related organizations to rapidly launch country-wide procedures that were easy to use and inexpensive. Body temperature measurement with non-contact infrared thermometers (NCITs) is among the most common procedures, both in hospital settings and in many other entities. However, practical hospital experiences have raised great doubts about the procedure's validity.Aim: This study aimed to evaluate the validity of the body temperature measured using NCITs among oncological and transplant patients who took the polymerase chain reaction test for SARS-Cov-2 PCR+ and PCR- in a Romanian Hospital.Methods: Body temperature was measured for 5,231 inpatients using NCITs. The cutoff point for fever was equal to or above 37.3°C. Patients then completed a questionnaire about their symptoms, contact, and travel history.Findings: Fever was detected in five of 53 persons with PCR+, resulting in a sensitivity of 9.43% (95% CI, 3.13–20.66%). No fever was verified in 5,131 of 5,171 persons with PCR-, resulting in a specificity of 99.15% (95% CI, 98.86–99.38%). A defensive vision of NCIT procedure (maximum standard error only in favor) had a sensitivity of 15.09% (95% CI, 6.75–27.59%).Conclusions: The use of NCITs in a triage provides little value for detection of COVID-19. Moreover, it provides a false sense of protection against the disease while possibly discriminating individuals that could present fever due to other reasons, such as oncologic treatments, where fever is a common therapeutical consequence. The consumption of qualified human resources should be considered, especially in the context of the shortage of healthcare professionals worldwide.

Performance characterization of non-contact infrared thermometers (NCITs) for forehead temperature measurement

The ability to assess the performance of a non-contact infrared thermometer (NCIT) may be limited due to the algorithms necessary to predict a reference site temperature (e.g., oral) from a measurement of the forehead skin temperature. The algorithm not only adjusts for the difference between the reference site temperature and forehead temperature, but may also account for hardware corrections, bias adjustments and emissivity settings. These algorithms are proprietary to the manufacturer and can be unique for each device. ASTM E1965-98 (2016) is a standard test method for the evaluation of NCITs. It includes forehead thermometers; however, the algorithm must be known or an unadjusted calibration mode must be accessible. This study evaluates 6 NCIT models (10 units of each) against the ASTM standard error criterion using a blackbody source. Units were tested within the manufacturer's operating and temperature measurement range specification. A method to evaluate measurement outliers and characterize each model's performance when the adjustment algorithm is unknown is proposed. Using this method, 5 of the 6 models had a predicted error > 0.3°C.

Clinical Efficiency of Non-Contact Infrared Thermometer over Axillary Digital Thermometer and Mercury in Glass Thermometer with Paracetamol

Fever is defined as rise in normal body temperature above 98.6°F. Clinical thermometer is a medical instrument for measuring human body temperature. The traditionally used mercury in glass thermometer was replaced by digital thermometer due to mercury toxicity. Non-contact infra-red thermometer is a non-invasive thermometer used for un-cooperative pediatric patients. The objective of this study is to determine the clinical efficiency of non-contact infrared thermometer over axillary digital thermometer and mercury in glass thermometer over a range of body temperature by using paracetamol in febrile patients. This descriptive hospital based cross sectional study was conducted from 5th December 2019 till 23rd August 2020 after ethical approval from Institutional Review Committee of Nepal Medical College and Teaching Hospital. Mercury in glass thermometer, axillary digital thermometer and non-contact infrared thermometer were used to measure body temperature in febrile patient. Body temperature was re-measured one hour after administration of paracetamol. Data was entered and analyzed with statistical package for social sciences version 16. Axillary digital thermometer has high predictability in the upper body temperature range (in febrile state) but its predictability is low in lower body temperature range (our normal body temperature). Non-contact infrared thermometer in comparison with axillary digital thermometer has lower predictability in both upper and lower body temperature range. Clinical efficiency of non-contact infrared thermometer is less than that of axillary digital thermometer and mercury in glass thermometer in febrile patients.

Use of non-contact infrared thermometers in rehabilitation patients: a randomized controlled study.

ObjectiveIn this randomized controlled study, we aimed to determine whether non-contact infrared thermometers (NCITs) are more time-efficient and create less patient distress than mercury axillary thermometers (MATs) and infrared tympanic thermometers (ITTs).MethodsForty-five rehabilitation inpatients were randomly assigned to one of three groups (NCIT, MAT, and ITT). Time required to measure body temperature with an NCIT, MAT, and ITT was recorded. We examined associations between time required to take patients’ temperature and measuring device used. Patient distress experienced during temperature measurement using the three thermometers was recorded.ResultsA significantly longer average time was required to measure temperatures using the MAT (mean 43.17, standard deviation [SD] 8.39) than the ITT (mean 13.74, SD 1.63) and NCIT (mean 12.13, SD 1.18). The thermometer used influenced the time required to measure body temperature (t = 33.99). There were significant differences among groups (NCIT vs. ITT, NCIT vs. MAT, and ITT vs. MAT) regarding patient distress among the different thermometers. Most distress arose owing to needing help from others, sleep disruption, and boredom.ConclusionThe NCIT has clinically relevant advantages over the ITT and MAT in measuring body temperature among rehabilitation patients, including saving nurses’ time and avoiding unnecessary patient distress.Clinical trial registration number (http://www.chictr.org.cn): ChiCTR1800019756.

Diagnostic accuracy of non-contact infrared thermometers and thermal scanners: a systematic review and meta-analysis.

Infrared thermal screening, via the use of handheld non-contact infrared thermometers (NCITs) and thermal scanners, has been widely implemented all over the world. We performed a systematic review and meta-analysis to investigate its diagnostic accuracy for the detection of fever. We searched PubMed, Embase, the Cochrane Library, medRxiv, bioRxiv, ClinicalTrials.gov, COVID-19 Open Research Dataset, COVID-19 research database, Epistemonikos, EPPI-Centre, World Health Organization International Clinical Trials Registry Platform, Scopus and Web of Science databases for studies where a non-contact infrared device was used to detect fever against a reference standard of conventional thermometers. Forest plots and Hierarchical Summary Receiver Operating Characteristics curves were used to describe the pooled summary estimates of sensitivity, specificity and diagnostic odds ratio. From a total of 1063 results, 30 studies were included in the qualitative synthesis, of which 19 were included in the meta-analysis. The pooled sensitivity and specificity were 0.808 (95%CI 0.656-0.903) and 0.920 (95%CI 0.769-0.975), respectively, for the NCITs (using forehead as the site of measurement), and 0.818 (95%CI 0.758-0.866) and 0.923 (95%CI 0.823-0.969), respectively, for thermal scanners. The sensitivity of NCITs increased on use of rectal temperature as the reference. The sensitivity of thermal scanners decreased in a disease outbreak/pandemic setting. Changes approaching statistical significance were also observed on the exclusion of neonates from the analysis. Thermal screening had a low positive predictive value, especially at the initial stage of an outbreak, while the negative predictive value (NPV) continued to be high even at later stages. Thermal screening has reasonable diagnostic accuracy in the detection of fever, although it may vary with changes in subject characteristics, setting, index test, and the reference standard used. Thermal screening has a good NPV even during a pandemic. The policymakers must take into consideration the factors surrounding the screening strategy while forming ad-hoc guidelines.

Comparative accuracy testing of non-contact infrared thermometers and temporal artery thermometers in an adult hospital setting

BackgroundNCIT are non-invasive devices for fever screening in children. However, evidence of their accuracy for fever screening in adults is lacking. This study aimed to compare the accuracy of non-contact infrared thermometers (NCIT) with temporal artery thermometers (TAT) in an adult hospital.MethodsA prospective observational study was conducted on a convenience sample of non-infectious inpatients in 2 Australian hospitals. NCIT and TAT devices were used to collect body temperature recordings. Participant characteristics included age, gender, skin color, highest temperature, and antipyretic medications recorded in last 24-hour.ResultsIn 265 patients, a mean difference of ± 0.26°C was recorded between the NCIT (36.64°C) and the reference TAT (36.90°C) temperature devices. Bland-Altman analysis showed that NCIT and TAT temperatures were closely aligned at temperatures <37.5°C, but not at temperatures >37.5°C. NCIT had low sensitivity (16.13%) at temperatures ≥37.5°C. An AUROC score of 0.67 (SD 0.05) demonstrated poor accuracy of the NCIT device at temperatures ≥37.5°C.ConclusionThis is the first study to compare accuracy of NCIT thermometers to TAT in adult patients. Although mass fever screening is currently underway using NCIT, these results indicate that the NCIT may not be the most accurate device for fever mass screening during a pandemic.

Validity of the Use of Wrist and Forehead Temperatures in Screening the General Population for COVID-19: A Prospective Real-World Study.

Background:We aimed to compare the accuracy of individuals’ wrist and forehead temperatures with their tympanic temperature under different circumstances.Methods:We performed a prospective observational study in a real-life population in Ningbo First Hospital in China. We consecutively recorded individuals’ wrist and forehead temperatures in Celsius (°C) using a non-contact infrared thermometer (NCIT). We also measured individuals’ tympanic temperature using a tympanic thermometer (IRTT) and defined fever as a tympanic temperature of ≥37.3 °C.Results:We enrolled 528 participants, including 261 indoor and 267 outdoor participants. We grouped the outdoor participants into four groups according to their means of transportation to the hospital: by foot, by bicycle/electric vehicle, by car, or as a passenger in a car. Under different circumstances, the mean difference in the forehead measurement ranged from −1.72 to −0.56 °C across groups, and that in the wrist measurement ranged from −0.96 to −0.61°C. Both measurements had high fever screening abilities in indoor patients. (Wrist: AUC 0.790; 95% CI: 0.725–0.854, P<0.001; forehead: AUC 0.816; 95% CI: 0.757–0.876, P <0.001). The cut-off value of the wrist measurement for detecting a tympanic temperature of ≥37.3 °C was 36.2 °C, with 86.4% sensitivity and 67.0% specificity, and the best threshold for the forehead measurement was 36.2 °C, with 93.2% sensitivity and 60.0% specificity.Conclusion:Wrist measurements are more stable than forehead measurements under different circumstances. Both measurements have favorable fever screening abilities in indoor patients. The cut-off values were both 36.2 °C.

Assessment of preferable site for temperature measurement using non contact infra-red temperature among pediatric patients.

Accurate temperature measurement with little or no discomfort that is safe, without risk of hospital-acquired infections or perforations, is the preferred choice of medical professionals in pediatric settings. The objective was to discover the preferable site for body temperature measurement using non-contact infra-red thermometer (NCIT) among pediatric patients. NCIT measurement at mid forehead (F), right temporal region (T), right side of neck- over-carotid artery area (N), jugular notch (J), sternum (S), umbilical region and sublingual region (U) were compared with digital axillary temperature (DAT) in a single attempt in 500 patients, aged between 2 to 5 years with fever. Data was analyzed using Pearson's correlation, paired T-test and Bland-Altman plot to assess the correlation and agreement between the DAT and NCIT sites. The mean temperature of NCIT-T (38.42 ± 0.64 °C) was more agreeable with DAT (38.42 ± 0.63 °C) compared to other body sites. The minimum mean bias of -0.00480 °C was noted for NCIT-F with 95% CI of -0.164-0.15; however, NCIT-F revealed many outliers as compared to NCIT-J. A strong positive correlation existed between DAT and NCIT sites (r value: 0.99-0.98). However, significant difference was found between DAT and NCIT-N, NCIT-F and NCIT-U (p value < 0.0001). NCIT-J is the most preferable choice for measuring body temperature and can be interchanged with DAT. It will help to deliver fast results with enhanced patient comfort due to its non-invasive nature.