Forehead thermometers, sometimes called temporal thermometers or classified in the more general category of infrared thermometers, which also includes ear thermometers, offer rapid, non-invasive temperature readings. Some temporal thermometers draw criticism for being hard to use properly, but once you master the basic swipe-and-read technique -- and learn to compensate for variables like a sweaty forehead -- a temporal thermometer is so unintrusive that you can even use it on a sleeping child.
The temporal thermometer with the best reviews we saw is the Exergen Temporal Artery Thermometer (Est. $30), which draws excellent accuracy scores from a leading consumer research lab, and very good scores for its repeatability and features. Many of the users who review this product are nurses who use the professional version at work, or parents who've seen their pediatricians using the professional version of this thermometer and wanted the home version for themselves.
The big caveat is that poor technique can lead to inaccurate results. However, the Exergen temporal thermometer's accuracy has been proven in a number of clinical studies, including a study published in the journal Pediatric Emergency Care positing that temporal scanning might displace rectal temperatures as the preferred temperature-taking method in a pediatric emergency room.
Once you've conquered the learning curve, reviewers say the Exergen is quick, efficient and easy to use: Just push the button, swipe the thermometer across your child's forehead, and release the button. The TAT-2000C returns results in just a couple of seconds, and parents love being able to take a sleeping child's temperature without waking him up. A beep and flashing light let you know the reading is ready, or can be turned off so as not to wake your child.
The Exergen Temporal Thermometer also draws praise from experts like Jennifer Wolf, About.com's expert on single parenting, who says it's just as easy to use on yourself as on a child. She also appreciates that this thermometer doesn't provoke any anxiety in her child, unlike trying to hold an oral thermometer in the right place can. The only real problem is that if your child wiggles too much, it's hard to get an accurate temperature. The Exergen stores the last eight readings in its memory and uses a widely available 9V battery.
Most parents -- and quite a few medical professionals -- feel the Exergen Temporal Artery Thermometer is an excellent investment for monitoring their child's temperature or their other family members. However, if you can't get your hands on the Exergen, or just want to save a few dollars, you may want to consider the Braun Forehead Thermometer (Est. $25). User reviews are a little more mixed for this thermometer than for the Exergen, but still mostly positive.
As with the Exergen thermometer (and really, any temporal thermometer), you should definitely read the user manual before using the Braun Forehead Thermometer. It has many of the same features as the Exergen model we just discussed, including quick results in just a couple seconds, a color-coded, illuminated display, and a beep to let you know the reading is complete; and it's equally useful for unobtrusively checking the temperature of a sleeping child.
However, international users may be upset that the thermometer only displays its readings in Fahrenheit -- it can't be switched to Celsius -- and the power/scan button for the Braun is located on the top of the unit, which makes it harder to use on yourself. The Exergen's power/scan button is on the underside.
Ultimately, although the Braun a good option, we still declare the Exergen TAT-2000C as top of the heap for temporal thermometers, thanks to the many clinical studies backing its performance and the many endorsements from healthcare professionals.