2581: Health Stats

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Health Stats
You will live on forever in our hearts, pushing a little extra blood toward our left hands now and then to give them a squeeze.
Title text: You will live on forever in our hearts, pushing a little extra blood toward our left hands now and then to give them a squeeze.


Cueball's has a smartwatch that tells him a new health statistic. It is a new watch or a newly discovered feature.

It seems to monitor the volume of blood currently in his left hand (specifically the one the watch is being worn on the wrist of, implying it tracks the inflow and outflow and maintains a running tally) and conveys this quantity in milliliters (ml). It also tracks other stats like his pulse, as seen later, but this is not what currently interests Cueball. Instead, he studies the blood volume information and finds it changing from moment to moment. This may be from a combination of his pulse (misaligned to the frequency of the updates) or the vertical position and attitude of his hand (he subtly changes the hand's position from panel to panel). It could just be inaccuracies in the data, an issue with all scientific instruments but more so for consumer devices used without practiced expertise - it is unlikely he has strapped the measuring device tight enough onto his wrist to give scientifically consistent results, even with such slight arm movements as he makes.

He reports his thoughts on this to someone off-panel, who is heard replying to all his comments. At first, Cueball just voices the assumption that the small change is normal and accepts the movement away from a number he had no reason to disbelieve as realistic. But then two measurements in a row both increases. Although all the changes are slight, compared to the magnitude of the numbers themselves, this freaks him out. He may be extrapolating these two data points into the future - if this rather selective trend continues, his hand may explode from its ever-increasing volume of blood. Either this, or Cueball noticed that the variation in the first three data points was ±0.025, but the final variation suddenly surpasses this level by ten times this range, massively redefining his evolving expectations.

For whatever reason he becomes anxious, a consequence of this is that his pulse also begins to rise, as also documented by the watch. This could simultaneously increase his blood pressure (not noted as being another monitored statistic) and in turn causing another rise in the volume of blood in his hand. Knowledge of the pulse increase makes him even more alarmed, which will cause a positive feedback loop at least in the short term.

The total difference between the maximum (22.09 ml) and minimum volume (21.81 ml) of blood in his hand is only 0.28 ml compared to an average of 21.9 ml, so less than 1.5% difference. This can realistically be assumed to be a normal fluctuation from heartbeat to heartbeat and/or with change of posture. For that matter, neither Cueball nor ourselves may have any idea what a normal volume of blood in his left hand would be. His comment in the first panel is that he's "not sure how to interpret" the initial measurement, and it might need rather uncommon medical knowledge to do so - even those who have learnt how much blood a typical human body should contain might be stumped by how much of that is just within a typical (or specific) human hand. However, he seems to have assumed that 21.83 ml was a normal measurement simply since it was the first one, he saw (a stereotypical preference for early information).

Just before his anxiety reaches breaking point, his off-panel friend begins to tell him to stop looking at the watch all the time but is interrupted mid-sentence by Cueball actually freaking out. This final outbreak causes his off-screen companion to tease him by saying that "We will treasure your memory", thus joking that Cueball will soon die from the blood loss when his hand explodes.

The title text continues with this teasing where the friend jokes that after his demise he will live on forever in his friends' hearts. From there he will thus also be responsible for pushing a bit more blood into his friends' left hands, now and again, so they can feel this as a squeeze to remind them of how they lost their friend to a left-handed blood explosion.

This is likely meant to parody the tendency of people to monitor minute details of their own health, pandered to by possibly misguided developments in personal meditech, without having a clear idea of what any of the data means. This is arguably much more common today with health devices readily available, which can give the average person data about their own body but often don't offer useful context. Cueball is apparently sufficiently fixated on data that apparent changes to any metric causes him to panic. He doesn't know what the blood volume of his hand means for his health, or even whether it's a useful metric, yet he obsesses over perceived trends in the data. The irony is that his very focus causes a more important metric (his pulse rate) to elevate. This may be intended to suggest that excessive fixation on one's own health can cause elevated anxiety. Ironically, this stress can potentially be more harmful than the things that the person has become upset about.


[Cueball is looking down and to the right at his bent arm, where a small device is radiating as shown with several small lines. Above him the message from the device is shown in a frame, which is divided in two by a line. The top part has one line of text, with a x at the end for closing the message. And below in the second half are two lines of text. Cueball is speaking to someone off-panel, who replies from a starburst at the panel's edge.]
Box title bar: New health stat!
Box: Left hand blood volume: 21.83 mL
Cueball: Oh. Cool. Not sure how to interpret that, but good to know, I guess.
Off-panel voice: I guess!
[Same setting but Cueball has turned to the left, still looking at his device on his bend arm. The message on the device is now only showing the message part, so it is no longer divided into two parts.]
Box: Left hand blood volume: 21.81 mL
Cueball: Huh, it's going down. I guess that happens.
Off-panel voice: Mhm.
[In a frame-less panel, Cueball now has both arms bent with his hands close together in front of him. He has once again turned toward the right, and is still looking at the device.]
Box: Left hand blood volume: 21.86 mL
Cueball: Oh weird, now it's going up higher than before.
Off-panel voice: Maybe you shouldn't look at-
[Cueball now holds his arm with the device outstretched towards the right, with his other arm bent in front of him a finger raised.]
Box: Left hand blood volume: 22.09 mL
Cueball: It's going way up! Is my hand exploding?!
Cueball: And now my pulse is rising! Aaaaa!!!!
Off-panel voice: So sorry. We will treasure your memory.

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Pretty late comic! GcGYSF(asterisk)P(vertical line)e (talk) 06:26, 15 February 2022 (UTC)

It's positive feedback, not negative. Negative feedback is when the response is in the opposite direction of the stimulus (e.g. Cueball becoming more relaxed as blood pressure goes up) and often results in an equilibrium state. A vicious circle (positive feedback) by contrast is when the response ends up increasing the stimulus further, as is the case in this comic. 11:19, 15 February 2022 (UTC) https://www.albert.io/blog/positive-negative-feedback-loops-biology/#:~:text=Positive%20feedback%20occurs%20to%20increase,back%20to%20a%20stable%20state. 11:50, 15 February 2022 (UTC)

I feel Cueball's pain. My employer has a checklist where we are supposed to take our temperature every day before coming to work. My problem is, I run hot. My "normal" temperature is usually 99.6ish, not 98.6ish. I knew this for years prior to the pandemic - I used to be a frequent blood donor and would get turned away about a third of the time because they won't take anyone above 99.5. Even though I knew all this, the paranoia induced by daily monitoring and a value that would be abnormal for others but totally typical for me got so bad that I don't do it. No one is enforcing it at the door - it is basically the honor system, and it was causing me more anxiety than actually solving anything. 18:54, 15 February 2022 (UTC)

A simple "solution" to this, at least for forehead thermometers, would be to engage in some moderate exercise shortly before having your temperature taken, such that you get some perspiration on your forehead. Then you can discontinue the exercise, and the sweat will evaporate soon afterwards, resulting in a particularly low skin temperature for a short while. Dansiman (talk) 21:30, 15 February 2022 (UTC)
No one is taking my temperature - like I said, it is the honor system and they are expecting you to do it before you show up. My point is that doing so was creating anxiety much like Cueball's, with not a lot of utility to the acquired data. 18:27, 16 February 2022 (UTC)
'Google: 99.6 f to c' -> '37.56' Hmm, that seems very close to average. Why are those people so concerned about such a small difference compared to average body temperature? Beanie talk 20:11, 16 February 2022 (UTC)

I see this as mainly a joke on how consumer devices often provide more precision than is actually needed, and users don't understand that the extra precision is usually not significant. The only reason "normal" human temperature is 98.6F, to the 10th of a degree, is because average temperature was first measured in Celsius then this was convered to Fahrenheit. But 37C was originally rounded off from an average, so it wasn't precise enough to warrant using an extra decimal place in the conversion. Barmar (talk) 19:23, 15 February 2022 (UTC)

Also a saultory lesson in the misunderstanding of the relationship (i.e. that there really isnt one, at least reliably) between precision and accuracy. Without proper calibration, even moment-to-moment consistency of measurement can be sullied by it being (consistently) wrong, or wrongly read out. Adding more decimals may seem to give a more persuasive estimate, but doesn't do a thing to stop inaccuracy. 19:51, 15 February 2022 (UTC)

I think we can assume that customer devices have a significant inaccuracy but have build-in time consistency to increase the trust in the device. Thus, I don't think the inconsistency between two measurements can explain the variation. Since the hand is moved around on the comic strip positioning is a more likely cause. -- 20:10, 15 February 2022 (UTC)

Saw an article a few weeks ago on the nocebo effect of fitness gadgets ... could be related. https://www.bloomberg.com/opinion/articles/2021-12-15/wrist-size-fitness-gadgets-make-for-great-gifts-but-beware-of-the-nocebo-effect Boatster (talk) 00:02, 16 February 2022 (UTC)

Just a side note: 72.961% of all readers trusts fictional data more if it has lots of decimals. 11:26, 16 February 2022 (UTC)

True fact: When the height of Mount Everest was first accurately calculated, the result was 29,000 ft. That was within a precision of one foot, but looked like it was rounded to the nearest 1,000, so they announced it to be 29,002 ft instead to actually look as accurate as it was (or had been!) precise.
Incidentally, that figure was established from measurements taken from no closer than 100 miles from the mountain (due to local politics and other difficulties) that had to account for atmospheric refraction, as well as the curvature of the Earth, etc. The current official measure, with 'hands on' access, is 29,031.7 ft. The difference (of 9.66m, to put it into modern units) is slight. If you assume it is changing directly in line with the average rise of the Himalayas, over the intervening 170 years, that's around 8.91m off. It's not possible to assess seasonal (snow-depth) changes, but that might cut another good fraction off again. Not bad for 1850s capabilities. 22:47, 16 February 2022 (UTC)

The explanation says that it is a new smartwatch, but the comic immediately made me think it was a new feature added by a software update. 15:55, 16 February 2022 (UTC)

how close is the volume of blood in a hand to a typical adult human? 20:16, 17 February 2022 (UTC)

This comic has me wondering if there is a fitness device that measures blood volume "down there"? That would introduce a hilarious new esports contest. These Are Not The Comments You Are Looking For (talk) 06:37, 20 February 2022 (UTC)

For the record, .28ml is approx 1/17th of a teaspoon JamesCurran (talk) 22:22, 17 March 2022 (UTC)