An Accuracy Study of Contact and Non-Contact Clinical Thermometers at Songklanagarind Hospital, Thailand

Objective: This study aimed to assess and validate the accuracy of contact clinical thermometers (CCTs), clinical digital thermometers (CDTs), temperature probes, and non-contact clinical infrared thermometers (NCCITs), which are commonly used at Songklanagarind Hospital.Material and Methods: The Medical Equipment and Maintenance Centre (MEMC) at Songklanagarind Hospital collected a total of 187 clinical thermometers, from various departments. This collection comprised of 45 temperature probes, 112 CDTs, and 30 infrared thermometers. All these thermometers underwent calibration at three distinct temperature points, via comparison with the secondary reference temperature standard (Pt100, SIKA). To assess the accuracy of the collected thermometers, an evaluation of the associated error and uncertainty was conducted. The maximum permissible errors (MPEs) were precisely defined as: ±0.2 °C and ±0.3 °C for CCT and ±0.5 °C for NCCIT.Results: The results revealed that all temperature probes, which represent 100% of the sample, demonstrated an average acceptable accuracy; determined by the average of the percentage of acceptable accuracy across three temperature calibration points, within the Maximum Permissible Error (MPE) range of ±0.2 °C. However, only 14% of the CDTs showed an average acceptable accuracy within the MPE of ±0.2 °C. Meanwhile, 51% of the CDTs met the MPE of ±0.3 °C. Additionally, 90% of the NCCIT demonstrated superior acceptable accuracy compared to the MPE of ±0.5 °C.Conclusion: This research emphasizes the significance of assessing the reliability and accuracy of clinical thermometers through calibration techniques; especially during the ongoing COVID-19 pandemic, which demands large-scale illness screening.