Pane Management — Part 1
The quantity of detail is an issue completely separate from the difficulty of reading. Clutter and confusion are failures of design, not attributes of information.
– Edward Tufte, Envisioning Information
We’ve been considering a high-level EHR user interface design that employs multiple panes within a single screen to display all the categories of data in a patient encounter.
In my last post, I discussed how mouse hovers or clicks can be used to expand and contract panes as needed. Excellent reader comments by Dr. Gregg and Dr. Robert Lafsky have made it clear it would be helpful to explore the limits of how much EHR data can be effectively displayed within an unexpanded pane.
In other words, can a relatively small pane present information at a high data density without creating clutter and confusion? Can multiple panes on a single screen be used to display most of the relevant data for a patient encounter, even before expanding or moving panes?
In my T-Sheet post, we explored one advantage of a single page or single screen view of the data. Each category of data is assigned to a fixed location on the page, allowing us to organize abstract data using our highly-evolved capacity to remember things by their spatial location.
A second advantage of a single page or single screen view is that we can rapidly access information by simply redirecting our gaze toward any part of the display. These rapid eye movements, lasting about a tenth of a second, are so integral to the way we take in and process information that most of the time we are not even aware of them.
Because data anywhere on a single page or screen is immediately available by using these ‘saccadic’ eye movements, we can simply retrieve it rather than remember it. Thus, the single screen design largely eliminates both the working memory problem and the cognitive costs of navigation. It also reduces complexity by reducing the total number of EHR screens needed.
For a single screen design to work, however, the individual panes need to be thoughtfully designed. Each pane needs to present a high density of data without clutter. We have already seen one problematic pane design, based on scrolling, that does neither.
Let’s return to the medication data set we’ve been working with. Here is the first part of the medication screen:
This design has lots of problems:
- It uses hard-to-read, all upper-case lettering for the drug names and dosages.
- The numeric values in the dosage column are not right aligned.
- The instructions are written in a form more appropriate for the patient than the clinician.
- The instructions present different classes of data (number, route, frequency, and notations) as text rather than in separate columns.
- The horizontal lines separating the rows of data are distracting.
- There is no way to re-order the medications in the list by importance, class or physician preference.
- Other than using all upper-case letters, the names of the medications are not emphasized.
- Abbreviations are underutilized.
- No effort has been made to eliminate redundant or self-explanatory information.
Many of these problems are improved with the redesign below:
Surprisingly, this small pane display contains almost as much information as the larger display above. Not only is this redesigned pane easier to read, it requires only 30% of the screen area needed for the first design. The redesign also uses the same number of pixels as the problematic pane with scrollbars design. Here are all three designs shown at the same scale:
Many computers now support monitor resolutions of 2.1 megapixels (full HD) or higher. The redesigned pane, at 57K pixels, takes up less than 3% of a full HD display:
By taking advantage of the greater display resolution now available and by using multiple well-designed small panes, the amount of EHR information available in a single screen view can be significantly increased.
Well-designed small panes can present detailed EHR information accurately, efficiently and simply. Multiple high data density panes displayed on a single screen, with each pane assigned to a fixed location, is an extremely powerful design. It allows us to use two highly-developed components of our visual system — our capacity to organize data spatially and our ability to access that data using rapid eye movements — to make sense of complex EHR information.
The take-home lesson is that no matter how good a user interface is, less is better. Eye movements are by far the easiest and most efficient way for humans to access or retrieve visual information. They beat using a mouse or other device to navigate, scroll, or expand panes hands down.
There will still be times, however, when expanded panes are needed. I look forward to discussing this issue in my next post.
Pane Management — Part 2
Rick Weinhaus MD practices clinical ophthalmology in the Boston area. He trained at Harvard Medical School, The Massachusetts Eye and Ear Infirmary, and the Neuroscience Unit of the Schepens Eye Research Institute. He writes on how to design simple, powerful, elegant user interfaces for electronic health records (EHRs) by applying our understanding of human perception and cognition. He welcomes your comments and thoughts on this post and on EHR usability issues. E-mail Dr. Rick.