Determination of core body temperature during pre-shift medical examination

The purpose of the research  is to develop a method for  indirect assessment of core body temperature based on measurements of heart rate   and palm  temperature using a  technical  equipment kit during a complex visual-motor reaction test. 
Methods. During the development process, a series of examinations were conducted with sequential measurements of CBT using a medical  thermometer and  the TEK employed  in the proposed measurement method. The obtained measurement results were processed using regression analysis, and based on the derived generalizations, a dataset was synthesized for training a machine learning regression model using the "random forest" algorithm. The developed measurement method was verified in accordance with the requirements for CBT assessment during pre-shift medical examinations. 
Results. As a result of the conducted research and the identified parameters (data preprocessing, data synthesis and the regression model algorithm), a technique for indirect assessment of CTT was developed, and its accuracy characteristics were determined. 
Conclusion. The developed method complies with the regulatory requirements for CBT measurement during pre-shift medical examinations. The method is applicable within an ambient temperature range of 18 to 35°C, measures CBT in the range of 35 to 42°C, and has an absolute measurement error of ±0.1°C. The method has been certified and registered by the Federal Agency for Technical Regulation and Metrology (Rosstandart). The certification number for the measurement method  is  2207/2411-(RA.RU.310494)-2023,  and  the  registry  entry  number  is  FR.1.32.2024.47935. Based on this method, specialized software (SSW) "Functional State Assessment" was developed. The SSW is registered with the Federal Service for Intellectual Property (Rospatent) and included in the register of computer programs. The state registration number for the computer program is 2024612210. The SSW, developed in accordance with the proposed method, is used in a hardware-software complex designed for conducting pre-shift medical examinations. 

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