Men aren’t the only ones who don’t read the instructions, part 1: The importance of headings and illustrations

Core Human Factors recently completed a usability study of a new injection device and ran into a phenomenon that stresses the importance of clearly conveying headings and illustrations in a product’s instructions for use (IFU). During this study, numerous users stated that they performed a certain step a particular way because of what they read in the heading and/or saw in the illustration; oftentimes users said that they did not bother to read the instruction’s captions. If captions contain additional important information on how to properly use a product (as these captions did), then only viewing an instruction’s heading and/or illustration  can lead to product misuse and potential safety risks.

The purpose of the study we conducted was to learn about the usability of an injection pen and its accompanying IFU, while the product was still in development. Sixty-nine representative users participated in the study; some participants had experience with similar devices currently on the market, while others were inexperienced. The study took place in a room with a one-way mirror that was set up to look like a living room, including a couch, rug, coffee table, and artwork. Although real needles were used (they attach to the top of the injection device), participants were given an injection pad meant to mimic skin and were told to strap the injection pad on their body where they would like to give the injection.

Study sessions were 1-on-1 with the participant and me, the moderator. I gave the participants a “prescription,” handed them the device and IFU, and asked them to use the product however they would in real life. After participants used the product the first time, they were asked to use the product again, this time following the IFU step-by-step, “reading a step and then doing a step, reading a step and then doing a step.”

Participant performance was observed (and captured on 2 video cameras: 1 close-up shot and 1 wide angle shot), and all use errors were recorded. A use error (i.e., Incomplete/Incorrect) was defined as “an act or omission of an act that results in a different medical device response than intended by the manufacturer or expected by the user.” At the end of the session, I probed the participant about every use error that occurred, with the intent of revealing the “root cause” (i.e., the underlying reason the use error occurred).

An interesting pattern I noticed emerging during the study was that participants were attributing their use errors to the fact that they did not read the full text for a particular instruction step, and instead only read the step’s heading or viewed the step’s illustration.  Three specific examples of this occurring are provided below. Note that the wording of the IFU text in these examples has been altered to protect the confidentiality of the product and the IFU.

Example #1

The heading said, “Select a spot,” but only the figure caption instructed users to select a spot AND clean the spot. As a result, several users, including females :o), did not clean the spot because they never saw the instruction to do so.

Furthermore, users reported not cleaning the spot because nothing in the step’s illustration indicated to them that they were supposed to clean the spot.  This particular illustration showed two large images of the front and back of a person’s body with appropriate spots that could be selected highlighted in blue, as well as a relatively tiny circle at the top-right corner of the diagram that contained a small picture of 2 overlapping squares with the top square labeled “Alcohol.” The body images stood out to the user but they did not even notice the small alcohol swab pictures.

A potential simple fix for this problem could involve changing the heading to “Select a spot and clean it” or “Select and clean a spot.” Furthermore, the image of alcohol swab could be enlarged or provided in a separate illustration than the ‘select a spot’ body images. Additionally, it may be useful for the alcohol swab image to depict a picture of a hand wiping the alcohol swab on a body part rather than just showing an alcohol swab.

Example #2

The heading said, “Press and twist,” but the figure caption instructed users to screw (instead of twist). As a result, some users attempted to just press the needle onto the device and give it a single twist, rather than pressing and screwing until there was a snug attachment.

A potential simple fix for this problem could be to change the heading to “Press and screw.”

Example #3

The heading said, “Testing,” but only the figure caption instructed users to actually do a test procedure. As a result, some users did not engage in any testing process and instead skipped right to the actual procedure.

Furthermore, the illustration for the ‘Testing’ step was very similar, nearly identical, to the illustration for the subsequent step, which was not a test but was the “actual” procedure.  Users reported not performing the test because the illustration appeared to be of the actual procedure. Additionally, while other headings were phrased to instruct the user, this heading was vague and provided no direction.

A potential simple fix for this problem could be to change the heading to “Perform a test procedure.” Additionally, it may be useful to add the text “test procedure” underneath the illustration for the test procedure.

To summarize, when reading a product’s instructions for use (i.e., quick guide), users may rely on just the heading and/or picture of an instructional step to know what to do. As such, headings and pictures need to be articulately worded and appropriately illustrated to convey all pertinent information, yet at the same time not overwhelm the user with too much information. Iteratively testing the headings and pictures for comprehension, especially without the accompanying subtext, can aid designers in creating instructions that lead to optimal performance and increased safety.

To cite: N Fink & M Egeth (2014, January 8). The Importance of Headings and Illustrations in Instructions [Blog Post]. Retrieved from: http://blog.corehf.com