Addressing Specific Audiences

As a scientist, you may find it challenging to present your work — or to explain scientific concepts in general — to a less specialized audience. More challenging still, however, is addressing a mixed audience of both specialists and nonspecialists. Here are specific tips for these two situations.

Whether you are addressing specialized or less specialized audience members, it is a good idea to convey early the motivation for the work you report so that they can relate to it — that is, you must bridge the gap between what they know or are interested in and what you will present. With nonspecialists, this gap is wider than with specialists. You might find it harder to convey the motivation for your work.

Nonspecialists lack comparison points. If you mention an absolute value, such as a power consumption of 5 mW, they might not know whether that is a small or a large amount for the device you describe, and they might not even know whether it is little or much in general. You can suggest that the power consumption is low or high by writing something like "as little as 5 mW" or "as much as 5 mW," but it is more helpful to provide the missing comparison point in the form of a relative value, as in "30 percent less than the most economical device to date" or "three times the average power consumption of devices of type X." Frequently, you can usefully combine an absolute value with a relative one, as in "5 mW, which is 30 percent less than . . . "

One type of comparison that is useful to all audiences but particularly to less specialized ones, including students, is the analogy. When you draw a parallel between a new concept you are trying to explain and one that is familiar to (or easily grasped by) the audience, you increase the probability that your audience will understand the concept and remember it. For example, you might say that the human genome encoded in DNA is like instructions stored in a library. The power of an analogy depends on how familiar the audience is with the comparison point (here, the library), and also on how consistently you can carry the analogy through your document or presentation. For example, if you can go on to meaningfully compare chromosomes to books in this library and genes to the pages in these books, then you have a more powerful analogy.

Nonspecialists also lack visual references; they cannot automatically picture what you are talking about. Visual material — appropriate for all audiences but crucial for nonspecialists — can include drawings and photographs. Drawings, which can abstract unnecessary details to focus on the essential idea, are best for conceptual explanations. In contrast, photographs, with their visual richness, give a better idea of what the "real thing" looks like. Thus, to explain a new chemical process, use a process flow diagram to discuss the flow of chemicals through the installation, but use a photograph of the pilot plant to provide a feel for size, appearance, and so on. Here, too, provide a comparison point for size, such as including a person in the photograph.

The essential strategy to addressing a mixed audience — from the unavoidable variation in expertise among peers to a mix of scientists and nonscientists — is structure, from the whole document or presentation to the individual sentence. You must distinguish between what everyone needs or wants to learn and what only some of them need or want to learn, and then structure your writing or speaking accordingly.

At the macroscopic level (the whole document or presentation), structure the content in levels of increasing specialization or decreasing interest. For a document such as a report or paper, place first what everyone needs or wants to know, typically in a summary or abstract (first level). Provide more detailed information in the report or paper itself (second level), possibly segregating in appendices what even fewer readers will need or want (third level). For a presentation to both specialists and nonspecialists, and especially when your time is limited, aim for the less specialized audience members in the presentation itself (first level), but foresee enough time afterwards for specialists to ask questions (second level) and perhaps create a companion document with more detailed information (third level). Feel free to include more specialized moments in the presentation itself, so you can hint at your deeper understanding, but make sure that these moments do not prevent less specialized attendees from understanding the remainder of the presentation.

At the microscopic level (the sentence), express in the main clause what is new or interesting to the majority of your audience members and relegate to a subordinate clause what fewer of them want or need to know. For example, consider the following sentences:

We have opted for connectors made of gold. Gold exhibits both high electrical conductivity and excellent resistance to corrosion.

Those who are well aware of the properties of gold might find the second sentence uninteresting or even patronizing, whereas the information is useful to less specialized readers. A better option is to subordinate the second clause, which is new to some audience members, to the first one, which is new to all members of the audience, in this way:

We have opted for connectors made of gold, given its high electrical conductivity and excellent resistance to corrosion.

In this revised version, the properties of gold are not presented independently but as a justification for the choice made. The new, compound sentence is more interesting for all readers, yet no information is lost for the less specialized ones.