Bastien and Scapin's ergonomic criteria


The Guidance criterion correspond all the means employed to assist, guide, inform, and direct the user during their interaction with the system.


This refers to the techniques used to make the user aware of their current situation and the actions they can take.

In practice:

  • Is a title given to each page?
  • Are the titles concise and relevant to the content?
  • Is the navigation menu present on every page?
  • Are action elements (links, call-to-action buttons, tabs, etc.) easily identifiable?
  • Do action elements change appearance when hovered over or when they are active?
  • Are key elements placed above the fold?
  • Are back buttons/icons available for easy navigation?
  • Are unavailable functions visually deactivated (e.g., grayed out) and non-clickable?
  • Etc...


This relates to the organization of elements in relation to each other. Two sub-criteria contribute to this:

  • Grouping/Distinction by Location: Separating or clustering elements to signify their differences or membership in a class by varying their spatial placement.
  • Grouping/Distinction by Format: Distinguishing or associating elements by assigning them different or similar graphic characteristics.

In practice:

  • Is it easy for the user to distinguish between elements and identify information of the same type?
  • Are pieces of information of the same type graphically similar?
  • Are pieces of information of the same type grouped and located in the same place?
  • Are distinct pieces of information presented differently?
  • Do distinct pieces of information have a different placement?
  • Do navigation menus include separators to visually distinguish different elements?
  • Etc...


This involves informing the user that their actions have been acknowledged. The system's responses should be as fast, clear, and relevant as possible.

In practice:

  • Do user actions result in a visible and understandable system response (e.g., confirmation message)?
  • Are user inputs always visible?
  • Is information displayed during the loading of an action, file, or page (e.g., hourglass, loading wheel)?
  • Do clickable elements exhibit a "hover" effect upon mouseover (e.g., color change)?
  • Is the delay between the action performed and the feedback reasonable?
  • Are long processes indicated by a waiting indication (e.g., progress bar, remaining time)?
  • Is the failure of computer processes clearly indicated and understandable?
  • Etc...


It involves making elements easily readable to enhance the user's understanding of the system and its content.

In practice:

  • Does the text adhere to WCAG or RGAA accessibility guidelines?
  • Is the font readable and of an adequate size (e.g., avoiding italics and all caps)?
  • Is there sufficient contrast between text and background colors?
  • Are clickable elements visually prominent?
  • Are line spacing and line height sufficient?
  • Is the use of colors harmonious?
  • Do colors and shapes serve as visual cues for different page elements (e.g., sections, menus, text, headings)?
  • Etc...


The Workload criterion corresponds to elements that facilitate the user's activity. The goal is to minimize the user's cognitive and memory load as much as possible during their interactions with the system.


It consists of minimizing reading, inputs, and the steps the user must go through to achieve their goal as much as possible. Two sub-criteria contribute to this:

  • Concision: Reducing the effort required for each element of the system;
  • Minimal actions: Limiting the number of steps to follow.

In practice:

  • Is memorization minimized?
  • Is the amount of information to enter reduced to a minimum?
  • Are the mandatory steps for the user brief?
  • Is the number of steps in a procedure minimized?
  • Are shortcuts provided?
  • Does the system anticipate user needs by highlighting the most frequent or relevant choices?
  • On long pages, is there an anchor to return to the top of the page?
  • Is the page width adapted to different devices?
  • Etc...


This involves simplifying the interface and reducing the perceptual and memory load on the user to provide only useful information for their experience.

In practice:

  • Are the perceptual efforts required of the user acceptable?
  • Are the animations discreet, limited in number, and controllable?
  • Is the quantity of information displayed simultaneously and the number of choices available acceptable?
  • Are the different information blocks sufficiently spaced apart?
  • Are filtering and sorting features provided?
  • Do illustrations and icons serve a purpose for the user or their experience?
  • Is the span of attention considered (average short-term memory storage of 5±2 items)?
  • Do text lines contain an average of 55-75 characters (including spaces) on the computer and 30-40 on mobile devices?
  • Etc...


The Explicit Control criterion corresponds to the system's consideration of any explicit action by the user, as well as the control the user has over their own actions.


This corresponds to the explicit relationship between the system's operation and the user's actions. The system should only perform the operations requested by the user, at the moment they request it.

In practice:

  • Do operations trigger with explicit consent from the user?
  • Does processing start immediately after the user's action?
  • When an operation doesn't start immediately after the user's action, is it indicated that it will be delayed or cannot be performed?
  • Do actions with significant and/or irreversible consequences require explicit confirmation from the user?
  • Etc...


This corresponds to the control that the user must always be able to exercise over ongoing computer processes.

In practice:

  • Can reversible actions be canceled at any time by the user?
  • Can an ongoing operation (e.g., filling out a form) be paused and resumed by the user?
  • Is it easy for the user to go back?
  • Is the opening of new windows explicitly controllable by the user?
  • Do multimedia elements leave control to the user (play, rewind, volume, pause, etc.)?
  • Etc...


The Adaptability criterion corresponds to the system's ability to adapt to the context, characteristics, preferences, and needs of the user.


This concerns the means that allow the user to customize the interface according to their needs. It involves offering different ways to accomplish the same task.

In practice:

  • Are different means provided to trigger the same command (e.g., icon, keyboard shortcut)?
  • Can primary actions be performed both with the keyboard and the mouse?
  • Is the system configurable according to the user's preferences?
  • Are displays that are not useful to the user deactivatable?
  • Is it possible for the user to create custom shortcuts?
  • Are means provided for visually impaired and blind individuals?
  • Etc...


This concerns the methods employed to adapt to the user's level of experience (from novice to expert).

In practice:

  • Are the contents adapted to all users (e.g., explanation of technical terms)?
  • Do search functions offer basic and advanced options?
  • Is task completion guided for the user?
  • Is access to shortcuts for quickly achieving goals available to the user?
  • Do error messages provide a more in-depth version for experts?
  • Etc...


The error management criterion corresponds to the means implemented to reduce errors, anticipate problems, and facilitate their correction when they occur.


Corresponds to the means for detecting and preventing input or command errors, as well as any actions with adverse consequences.

In practice:

  • Are measures in place to prevent user errors (e.g., indicating data format to input)?
  • Does the system provide a help section (e.g., assistance, chat, tooltips)?
  • Are manual inputs minimized to the bare essentials?
  • Is confirmation requested from the user before triggering an irreversible action?
  • Are mandatory or optional input fields clearly marked?
  • Are input fields accompanied by clear labels and, if necessary, examples of content?
  • Etc...


This corresponds to the readability, relevance, and accuracy of the message presented regarding the reasons and nature of errors, as well as the expected actions to correct them.

In practice:

  • Are error messages understandable, self-contained, and explicit?
  • Are error messages concise, readable, and placed in a suitable location?
  • Do error messages indicate the origin and nature of the error?
  • Do error messages provide guidance on how to correct the issue?
  • Are error messages non-blaming?
  • Do error messages remain displayed until the issue is resolved or corrected?
  • Are error messages accompanied by elements to resume navigation (e.g., a call-to-action to return to the homepage)?
  • Etc...


Corresponds to the information and means made available to the user to allow them to correct their errors.

In practice:

  • Does the system correctly detect user input errors?
  • Is an error promptly communicated to the user?
  • Do error messages provide guidance on how to correct the error?
  • In the case of a form, is an error easily noticeable by the user?
  • Can users easily undo input errors or unintended actions?
  • Are means available for reporting a system error (e.g., a reporting call-to-action)?
  • Does the system offer alternatives (e.g., alternative search) in case of errors?
  • Etc...


The Homogeneity/Consistency criterion relates to the overall harmony of the system, adherence to design choices, and the existence of a stable framework. In other words, what should be different is effectively different, and what should be identical is indeed identical.

In practice:

  • Is the interface visually stable from one page to another?
  • Are typography, colors, alignments, spacing, and call-to-action elements consistent from one page to another?
  • Is the placement of key elements the same on all pages (e.g., the menu)?
  • Are state changes and click consequences consistent for identical elements?
  • Does the same word have the same meaning throughout the interface?
  • Do the same sequences of actions have the same effects from one page to another?
  • Etc...


The criterion of Significance of Codes and Designations corresponds to the system's ability to use understandable terms and codes that are adapted to the user's habits.

In practice:

  • Do the labels of clickable links reflect the content of the destination page?
  • Are button labels explicit about the consequences of clicking?
  • Are the icons used understandable and appropriate?
  • Are abbreviations limited and explained?
  • Is the language used understandable to the user?
  • Are technical terms specific to your company/domain defined?
  • Are the colors, symbols, and terms used adapted to the cultural codes of the target audience (e.g., green for validation and red for errors)?
  • etc...


The Compatibility criterion corresponds to the system's ability to adapt to the user's characteristics, operating mode, the device being used, and the context of use.

In practice:

  • Is the interface adapted to the target user?
  • Is the language of the interface understandable?
  • Is the vocabulary relevant to the target audience?
  • Is access to commands adapted to the context of task completion?
  • Is the interface compatible across different devices, browsers, and screen sizes without distortion or loss of content?
  • Is the target interface consistent with the primary context and device of use (mobile-first, responsive, or adaptive)?
  • Is data input in forms done in a logical order for the user?
  • Can the user choose their own display and sorting criteria?
  • Etc...