Oral and Rectal Temperatures of Man

The so-called normal body temperature of a healthy person has been stated categorically to be 98.6 F. (37.0 C.). Another clinically accepted truism is that the rectal temperature is 1 degree Fahrenheit higher than the oral, or approximately 99.6 F. (37.6 C.). These values are, of course, merely approximations and can, therefore, be highly misleading. The origin of these figures is somewhat obscure. The following review of the literature is an indication that even the value 98.6 F. for the oral temperature is undoubtedly incorrect. Schaefer¹summarized the oral temperatures obtained by a group of eight authors who published their material between 1848 and 1898 and found it to be 98.3 F. Davy²in 1845 reported a mean value of 98.4 F. for the oral temperature obtained during the working day, while Pembrey and Nicol³found it to be 97.2 F. Allbutt,⁴who introduced the present