A good thermometer is your first line of alert against fever, a sign of many communicable diseases. For obvious reasons it has to be, above all else, highly accurate.
But it does not necessarily have to be highly priced. On the contrary, the reverse is true.
As shown in a Consumer Council test on 25 models of home electronic (digital/infrared) thermometers, the more traditional digital stick thermometers measuring oral, armpit or rectal temperature clearly stood out among the other types in overall test performance.
All the 7 samples in this category were awarded, without exception, the top rating of 5 points; rating of test performance was based on accuracy (50%), repeatability (40%), and mechanical strength (10%).
Ironically, these top performers were also among the least expensive available from $43 to $179. The other types of thermometers tested were in the higher price bracket ranging from $229 to $850.
In general, the 18 samples of the more costly types performed reasonably well, with variations in overall test performance from 3 points (1 sample) to 5 points (3 samples). Most were between 4.5 points (8 samples) and 4 points (4 samples). Relatively minor deficiencies found included:
- 3 samples were less than satisfactory in laboratory accuracy test with an average deviation of more than 0.2℃.
- The thermometers were used to measure test objects with temperatures of 37.0℃, 38.5℃ and 40.0℃ each for three times to assess whether they could repeat the same reading every time. One sample, however, was found to have a maximum difference (deviation) of 0.3℃ among its measurements of 37.0℃.
- The stringent tumbling test had uncovered relative weaknesses in the mechanical strength of some samples, including detached cover and broken clip, some permanent black spots in the temperature reading display, and permanent damage to the battery compartment cover, although ordinary mechanical shocks occurring in everyday life should not affect performance in any way serious.
In terms of convenience of use, understandably, inexpensive traditional stick thermometers were less favourably rated relative to the types measuring body temperature through ear, forehead, temporal and a spot behind the ear lobe.
Convenience of use was based on trial user feedback on such aspects as the product user instructions, suitability to infants and young children, preparation needs for measurements and ease of taking measurements. Users generally found the digital oral/armpit/rectal type took a relatively longer time to obtain a body temperature reading.
When selecting a thermometer, one should consider the user's age, health condition and the method of temperature measurement, and see whether it is suitable and convenient to use, particularly with infants and young children.
It is important that consumers should study the user instructions carefully, in particular with the forehead type thermometers - the exact location of where the probe should be placed; the distance between the probe and the forehead; and the movement of the probe during measurement could all vary among different models.
Moreover, users should always clean and disinfect the thermometer according to the instructions, and those with communicable diseases should use personal thermometers to avoid cross-infection.
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