I’m always amazed at how happy the voice on TV commercials sounds when describing a litany of horrible-sounding side-effects from a prescription medication. I was just watching the nice cartoon lady telling me about Abilify when I overheard this:

<queue birds chirping> <nice music playing> Contact your doctor if you have uncontrollable muscle movements, as these could become permanent. Other risks include decreases in white blood cells, which can be serious, dizziness upon standing, seizures –

Errr, wait, what the fuck? Can we not have the nice guitar strumming along with a quaint melody in the background while you tell me that if I take this pill I might not be able to control my muscles and might start having seizures? Your soothing, monotonous tone is both putting me to sleep and freaking me out at the same time.

We’ve all heard these side-effect warnings in commercials, or seen them on packaging in the tiniest tiny print. It’s not uncommon to hear some soothing voice say something like “Side effects include headache, drowsiness, sore throat, and death.” Uhhhh. I’m ok with most of those, but one of these things is not like the other.

And yet the commercials or fine print don’t really tell you what’s likely to be a side effect versus what’s unlikely. Turns out, though, that if you do some research, the significance of the side effects of various prescription pills are available online. You just have to dig. For example, here’s the product sheet for Zoloft. And it has a section about side effects that looks like this:

Now we’re getting some real numbers. If only there was a way to quickly see what the most common side effects of various drugs were at a glance.

Here’s my take on redesigning the information presentation. We’ll start off with a fun one, which is the popular anti-depressant Zoloft:

Ain’t that a bitch? I guess the good news is if you’re nauseous, then ejaculation failure might not be that big a concern. The side-effects are sized by computing the difference in the percentages between the placebo group and the group taking the medication. In this case 14% of patients taking Zoloft experienced ejaculation failure, versus only 1% in the control group.

Here’s another anti-depressant, Abilify (source data):

And now of course we have other drugs to counteract some of these side-effects, so why not trying to counteract the negative Zoloft effects by popping a Viagra? Here are the new side effects you get to enjoy (source data):

And once that Viagra’s worn off you might be looking for a cigarette. But try Nicotrol (details) instead, you’ll get to take your chances with the following side effects:

Now at a glance you can see what you need to worry about and what you don’t. I imagine these beautiful labels on the side of the prescription boxes Well, at least I can dream.

This is another experiment in visualizing 24-hour cyclical data. My last post explored a method of linear representation (the Double Time Bar Chart). Linear representations have problems when it comes to showing the cyclical nature of time data (ie there is no start or end of a 24 hour cycle).

Inspiration

When trying to think of visual representations of never-ending cycles I was inspired by the infinity symbol. It’s a great symbol to show a continuous cycle, while at the same time being more visually interesting than a simple circle (fun fact: the infinity symbol dates back to 1655). The other iconography that came to mind when thinking about infinity is the hour glass. An hour glass not only represents time, but it also looks similar to a vertical infinity symbol.

My thought was that maybe I could combine the two to create a vertical infinity symbol that evokes the metaphor of an hour glass.

Back of the napkin

My original sketch of this concept was done on the back of a napkin. This is the first sketch, which shows how I was originally working with a horizontal infinity symbol.

I experimented with a few different options for how to show the data using fills. One of the sketches (if turned vertically) looks like an hour glass filling up with water on the bottom, reminiscent of the Wikileaks logo.

Drawing Infinity

The mathematical name for the infinity symbol is lemniscate, and more specifically the lemniscate of Bernoulli. With some good Googling you can find algorithms to draw the lemniscate of Bernoulli, which is what I did.

To start I divided the lemniscate into 24 segments, one for each of the hours of the day. My initial plot of the lemniscate in 24 parts looked like this:

I mapped the hours of the day onto this form, with 12pm noon at the very top and the infinity symbol crossing itself at 6pm/6am.

You follow the time by working your way around the infinity. If you start at the top of the symbol at noon, you would start moving around clockwise to 1pm, then 2pm, etc. You’ll reach the center at 6pm, at which point the symbol crosses itself and you then read it counter-clockwise around the bottom.

What you end up with is a way of dividing up the times of day into quadrants. The top-left quarter of the image is the morning, from 6am-12pm. Then the top-right is the afternoon, from 12pm-6pm. Then you have the evening in the botom left (6pm-midnight) and then late-night is in the bottom-right (12am-6am). These quarters match well with how I mentally categorize times of day.

Because the form crosses over itself you can actually read the chart almost in a left-to-right way for both the day (top) and night (bottom).

Drawing Data

The next step is to try to use this form to represent real data. Here’s an example that shows the distribution of driving under the influence arrests in San Francisco:

We can see that this particular crime is primarily a night-time activity that surges around midnight and starts falling off after about 2am. I’ve colored the range of 6am-6pm in orange to show day-time and the range of 6pm-6am in blue to indicate night-time.

For comparison here’s apartment burglary, which is mostly a day-time activity:

Once the viewer understands how to read the chart we can remove the labels and simply show the pattern. Here’s a comparison of a few night-time crimes:

Here’s a comparison of different types of burglary, some of which occur mostly during the daytime (residential burglary) and some of which occur in the afternoon and late at night (burglary of a store).

Small Multiples

Here’s a final example of many different crime types represented side by side to try to see how this chart works for comparisons.

Discussion

I’m not very happy with this chart in terms of the viewer’s ability to accurately read the chart. I also don’t think it highlights changes between hours enough. Often there are changes and trends that are easy to spot in the linear charts of my last post, but that are very difficult to see in these charts. Each hour is at quite a different angle than the hours on either side, which makes it difficult to compare two hours. You still get the big picture trends, like if a crime is a night-time or day-time crime, but the smaller trends are much harder to spot.

On the flip side, I really like the metaphors of the infinity symbol and the hourglass. On an artistic and philosophical level I think those metaphors make this a really beautiful visualization. Too bad it’s not also effective