About.com states that it is not necessary to add a degree to temperatures taken with ear or temporal thermometers. It's recommended to take a temperature two or three times and average the results when using ear or temporal thermometers.
WebMD explains that ear, or tympanic, temperatures and rectal temperatures typically run 0.5 to 1 degree Fahrenheit higher than the oral temperature. Armpit, or axillary, temperatures and forehead, or temporal, temperatures are usually 0.5 to 1 degree lower than an oral temperature.
About.com suggests that rather than adding or subtracting degrees from a recorded temperature, it is best to report the actual thermometer reading to a doctor and tell him what type of thermometer was used.