What unit should we use? Metric or imperial?

Question

Example question: Can being cold or wet be a significant influence in getting the common cold?

When I read that question, the "coldest" temperature in that question is 60 degree, while in my knowledge, the human temperature is 37 :)

Should we:

• convert all imperial units to metric because most place of the world use metric?
• show both number so that everyone can easily understand?
• just use the units which we are familiar with because converting units is not a big deal?

By the way, to type the degree symbol (°), use Alt+0176 or Alt+248 on PC, option shift 8 on Mac, or hold down in number zero in iPhone or iPad.

Answer 1

Think about it like writing a recipe. If I say that you should preheat your oven to 200 degrees, I should really specify what kind of degrees. 200 Degrees F would barely slow-roast a chicken, while 200 Degrees C would surely put some brisk in your brisket.

When talking about temperature, just note the scale. It's pretty obvious what I'm using if I say "Anything close to 40 degrees is a high fever and should have you hunting for some paracetamol", but it's nice to note. I also don't recommend strictly enforcing this in cases where it's just obvious what is meant.

Everything else is pretty straight forward for conversion.

While the world is advanced, some folks still have to try and fill 60% of a tablespoon, while the rest of us just pour out 10 ml and be done with it. Let's not badger anyone unless there really is ambiguity.

And as it's currently a balmy 313.15 degrees Kelvin where I am, I'm off to get something cold and lemon-y.

Answer 2

Note that you won't be able to force the users to write the units you want. On Cooking, we're glad when they at least think of writing down which scale they are using, C or F, but they frequently don't do that.

We have made the experience that they don't complain when their post is edited to show both units, so we frequently do this. But it is based on a guess what they meant. Luckily, it's frequently visible from context from us (we hope nobody's fridge went to 45 C), I don't know how it will be on Health.

If Health decides to enforce a single unit, the consequences will be

• the majority of users will disregard the guidelines
• people will have to take the time to edit lots of others' posts. If only a few editors do it, it may feel like a Sisyphean task after time.
• if there is one unit chosen, people will grumble when the post they wrote and understood is changed to a unit they can't understand or relate to. So the only way to not disgruntle them is to edit posts to contain both units.

See also the old Cooking discussion on enforcing standard units (despite the accepted answer, almost nobody bothers with edits - maybe C to F are a bit more common, because there are more Americans around) and this request which resulted in a user script. I don't use it, but I hear some of the regular users are happy with it.

Answer 3

If you really want to have a default, that should be metric. There is a clear consensus in favor of metric in the sciences. I have never seen imperial units used in peer-reviewed papers.

Both biological and medical journals will insist on using metric and won't allow imperial. At least, none of the ones I have published in or read in my ~15 years as a biologist do.

So, if you're going for a standard, use metric. Whether or not this site really needs a rigorous standard for this is another question. This is not a peer-reviewed journal, it's a site for "medical specialists, students, dietitians, and anyone with health-related questions". However, if a standard is to be decided I would recommend it is the standard already adopted in the broader field of the health sciences: metric.