what’s the right amount of detail to include in a single visualization?
Through virtual and in-person workshops around the globe, we have taught tens of thousands of people how to communicate effectively with data. This series captures some of the noteworthy questions we hear during those sessions—and our answers.
How do I know how much detail to include in my slides? I want to make sure the context of the communication is clear, but I don’t want my visuals to feel cluttered, or to have so much explanation that my audience thinks I’m talking down to them.
Our workshops emphasize the importance of simplifying our communications without OVER-simplifying them. We want to get rid of anything that gets in the way of understanding—removing unnecessary lines, digits, data labels, and so on—but we also don’t want to remove SO much information that we leave our audiences guessing about what they’re even viewing.
How much context, then, is necessary to include, so that we have an understandable (but un-cluttered) visual, presented with enough background information for the viewer to grasp its meaning, with the key insights and recommended actions emphasized?
When we’ve addressed this question in the past, we’ve relied on the always-true, if sometimes unsatisfying, response of, “It depends.” Every situation is unique, and there’s no checklist or scorecard you can use in every circumstance to ensure that you’ve hit the perfect amount of detail.
However, there are a couple of considerations that will help you zero in on just the right amount of context to provide in your particular communication, and those are: the method of delivery you’ll be using; and the relationship you have with your audience.
Delivery: live vs. written
When you present something in a live or a virtual setting, you have tremendous flexibility. You can respond to audience cues and questions; you can add or skip over details and background information on the fly, based on the reactions you’re getting; and you can (and should!) prepare more slides, to visually support your step-by-step explanations and keep viewers’ attention (particularly in an online communication). You can get away with having less context and detail physically written down or shown because you are there, live, to fill in any blanks.
This is not the case in written communication, where the level of explicit detail must be higher. Without you present to facilitate the flow of information, your words and visuals must paint the full picture (and address at least first-order questions) on their own. In addition, people have a higher tolerance for detail on a slide, or on a single page of a report, if they can consume it privately at their own pace versus in a live group setting. Because of this, the level of detail necessary for written communication is much higher than for a presentation.
To see what these differences look like when we start from the same data, try your hand at the “optimize your output” exercise in the storytelling with data community.
Relationship: who are you to the audience (and vice versa)?
Even when we take care to identify our intended audience—as we should, whenever we communicate with data—we should also think how they will perceive us. Perhaps we have worked with this group before, or with mutual acquaintances; and as a result, will begin the presentation having already established our bona fides. If you have an established, trusting relationship with your audience, you can get away with showing less detail without your audience questioning it.
On the other hand, we might be a completely unknown quantity…or we might have had to deliver unwelcome news in prior presentations to this same group. If you haven't established a basis of trust with your audience, or if they harbor negativity from prior communications, you may need to show more detail explicitly. That way, your audience is less likely to feel that you are trying to mislead by only showing the parts that back up your story and selectively discarding the rest.
You can test out different structures and levels of detail in your presentation early in the creative process, by employing the decidedly low-tech but incredibly effective technique of storyboarding. If you don’t storyboard on a regular basis but would like to see how it can be put into action, our exercise “storyboard your project” can give you some guidelines for getting started.