A recent review of the effectiveness of the different types of thermometers has found that those types that measure skin temperature are a little less accurate than those used internally, according to an article on npr,org.

Dr. Daniel Niven, an intensive care physician with the Peter Lougheed Center in Calgary and head of the review, said there was no reason to chunk your current thermometer and go out an buy a new one, adding oral and ear thermometers are reasonably accurate as well.

Niven and his team reviewed data from 75 studies across the globe, looking at measurements to see how the many types of thermometers compared to each other, checking data from measurements taken from the mouth, ear, armpit and on the forehead by devices identified as peripheral thermometers.

Comparing those results to data from devices known as central thermometers, those inserted into the rectum or into the bladder with a catheter, the team found that the peripheral thermometers were off by as much as 1.5 degrees.

The data analyzed included records from some 8,600 adults and children, but did not include infants or toddlers.

Noting that many Intensive Care Unit’s (ICU’s) prefer the armpit measurements for patients, he hopes this new data will encourage more hospitals to use the more invasive but more accurate central thermometers.  Niven added that an incorrect normal reading could result in an infection that would go undetected, and that would be especially worrisome in ICU’s, where “important opportunities to treat significant infections” could be overlooked.

Niven and his team also say that for parents of small children, it would be best to use the thermometer that measures the temperature in the mouth or the ear, especially for cases of runny noses and sore throats.  The team said these types of measurements were more accurate that the armpit or temple thermometers.

The American Academy of Pediatrics recommends using rectal thermometers for children under the age of three.

A body temperature of 98.6 is usually considered normal, but since many people’s “normal” is different, anywhere between 97 and 99 is acceptable.