Placing your hand lightly on your child's forehead often provides the first clue that there's a fever. Then you'll need a more reliable way to confirm your suspicion. That's when a good thermometer is necessary--meaning one that's highly accurate. For babies under 3 months old, temperatures should be taken rectally, and any fever in this age group is typically considered an emergency. When in doubt, call the doctor.
But what type of thermometer should you choose? Some digital stick thermometers can be used to take a rectal, oral, or armpit temperature. Check manufacturer instructions before use. Also available are infrared devices, which are either designed to be used on the forehead, in the ear, or without any bodily contact at all (non contact).
The American Academy of Pediatrics (AAP) recommends taking a rectal temperature in infants and children younger than 3, because it's the most accurate measurement. An armpit temperature may be preferred for screening, but it's the least accurate. If the armpit temperature is above 99 degrees F, check it with a rectal temperature.
In children older than 3, taking an oral temperature is acceptable. An ear thermometer is another option for older babies and children. It gives quick results, but placing it can be tricky and you may not get the same temperature in both ears. Temporal artery thermometers, which read the infrared heat waves released by the temporal artery in the forehead, are acceptable for use in babies 3 months and older but only as a screening device for younger babies. Ask your child's doctor for advice.
Whatever method you choose, the thermometer you purchase should be easy to use and comfortable for your child. With this in mind, our recent tests of 10 fever thermometers not only measured accuracy but also included comments from 19 children ages 4 and up about their comfort level with each thermometer.