A Single-Screen EHR Design for the Patient Encounter
The benchmark . . . for all navigation techniques should be the saccadic [rapid] eye movement. This allows us to acquire a new set of informative visual objects in 100-200 [milliseconds]. Moreover, information acquired in this way will be integrated readily with other information that we have recently acquired from the same space. Thus, the ideal visualization is one in which all the information for visualization is available on a single high-resolution screen. – Colin Ware, Information Visualization: Perception for Design
I would like to bring together some of the user interface designs we have been considering and propose for discussion a single-screen EHR design for a patient encounter. Before presenting the design itself, it is useful to recall the design concepts covered in previous posts:
- The human visual system is very good at organizing data spatially (Why T-Sheets Work; Pane Management – Part 2).
- We excel at grasping patterns and seeing relationships among data elements when they are presented in a single view, but have limited capacity to remember these elements when they are distributed across multiple screens (Humans Have Limited Working Memory).
- The most efficient way to navigate visual space is by using rapid (saccadic) eye movements (Fitts’ Law).
- Using a large, high-resolution screen supports navigation by saccadic eye movement (Pane Management – Part 1).
- When we do need to navigate using a mouse or other input device, we can reduce the cognitive costs by making the targets large and reasonably close (Fitts’ Law).
- It is often easier to grasp patterns visually than mathematically or verbally (Computer-Centered versus User-Centered Design).
- It’s easier to find patterns and solve problems with data presented compactly and grouped visually – using columns, rows, and formatting – than with data presented as free text (Pane Management – Part 1).
- Using vertical and horizontal scrollbars to navigate small panes requires cognitive effort and doesn’t solve the working memory problem (The Problem with Scrolling). It is preferable to display an overview of the data and use mouse hovers or clicks to display details as needed (Overview with Details on Demand).
A large single screen with high resolution, for instance 1920 x 1080 pixels (full HD), is used to display all the categories of data for a patient encounter on a particular date. Each category of data is assigned to a pane of fixed size and location on the screen:
Because humans are able retain about nine spatial locations in visual working memory (although we can only remember simple visual objects or patterns contained in about three to five of them), a set of nine panes arranged in a 3×3 grid was chosen for the high-level design.
The figure below shows this same screen design populated with data from a patient encounter:
Click on the thumbnail below to see the design at higher (but not full) resolution:
The figure below shows the Problem List pane:
A marker (for instance, an asterisk) indicates that more detail is available for a data field. Detail can be displayed by hovering or clicking, as shown below for Diabetes Mellitus:
and for transient ischemic attack (TIA):
The same high-level design is used for all panes, as in the Exam pane below (size slightly reduced):
Again, hovering over or clicking on a line with an asterisk brings up more detail for that data field:
The design allows default or normal findings to be summarized:
while still making the full default text available on demand:
As an alternative to expanding individual data fields, all the data fields within a pane can be simultaneously expanded by hovering or clicking on the pane’s title bar, as shown below for the Problem List:
An expanded pane will necessarily obscure adjacent panes, as below:
Even in this case, context is at least partially preserved because of the large high-resolution screen.
Expanded data fields:
- In order to maintain as much context as possible, data fields within an individual pane expand only to the minimum size required.
- More than one data field within a pane can be expanded at the same time, provided that the expanded fields don’t overlap.
- In order to maintain as much context as possible, panes expand only to the minimum size required.
- More than one pane can be expanded at the same time, provided that the expanded panes don’t overlap.
- The same single-screen design is used both for data entry and subsequent data review. Any pane can expand for data entry and then contract to its original size.
I would propose that this kind of single-screen design for a patient encounter, with all its interactive capability both within panes and among panes, should be thought of as the chart note. In this design, there is no separate text-based or PDF "completed note," except as needed for use outside the EHR.
The design above is a sketch – a design being considered, reformulated, and reworked. I tried to design it based on an understanding of how the human brain best takes in, processes, and organizes information. Its purpose is to generate discussion and debate. I look forward to your comments and suggestions.
Finally, there is a major caveat that comes along with the single-screen design presented here. A patient’s electronic health record is a longitudinal record, while the design above represents a snapshot in time. More on this in coming posts.
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.