The rate and extent to which chemical reactions occur

Costly. The forehead thermometer is among the most expensive thermometers in the market.

Varying Readings You may need to take 2-3 readings and use the average to identify your baby’s real temperature. This is because the temperature readings may vary depending on how you swipe the thermometer. For most parents, it takes some getting used to before they can master the art of picking an accurate temperature.

Heat Sensitive The forehead thermometer is sensitive to heat. Changes in the environment may, therefore, affect its accuracy. Also, if your baby is sweaty, this may also alter the accuracy of the reading.

Ear Thermometer

The ear thermometer is also known as the tympanic thermometer. Like the forehead thermometer, it also uses infrared technology to read the temperature inside your baby’s ear canal. To use it, you insert the tip of the thermometer inside your baby’s ear canal and press the button.

Advantages of the Ear Thermometer

1. 
   Fast Many brands merely take seconds to get a reading using the ear thermometer. It, therefore, saves parents their time. And although it is intrusive, it doesn't need to be in the ear for long.
   
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    Accurate If inserted correctly in the ear canal, the ear thermometer gives a very accurate reading and is, therefore, a reliable way of picking your baby's temperature.
   

Disadvantages of the Ear Thermometer

1. 
   Invasive The ear thermometer has to be placed inside your baby’s ear canal for an accurate reading. Parents often have to pull their babies ears and tilt their little heads to access the ear canal, a process most babies find downright uncomfortable and if they squirm around it can effect the reliability of the reading.
   
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