Easy access and navigation of historical measurement data stored in central laboratory software systems is important to support the documentation and, in particular, the traceability of measurement results. But it is also useful for some instruments to grant users access to past measurement data.

The need to work with centralized measurement data poses some unique challenges for developing the user interface (UI) of the instruments involved. It is important to achieve optimal usability so as to make working as easy as possible for users.

The usability or user friendliness of a measurement instrument or, generally speaking, of any product encompasses different aspects. Software systems, for example, are often judged by the findability of features and stored data and also by how much efficiency they provide, relative to the number of required navigational steps. Improving them during product development can be achieved by methodological procedures, also termed as usability engineering (for more details see info box).

Generalizing measurement data: a special challenge for lab workflows

When you compare the display sizes of measurement instruments with computer screens, it becomes clear that instrument users cannot be shown the same amount of data over the same time. Lab devices are optimized to take up as little space in the lab as possible. Therefore, users have to put more effort into navigating around. The exemplary lab application underlying our work posed the particular challenge of generalizing the data that the instrumentation generates. This needs to be done to make available the data originating from different instrument types (e.g. balances, titrators, spectrometers, pH meters) in a uniform way by a central laboratory software system, such as LabX. Enough flexibility should also be provided to search for the results either in relation to a sample or, alternatively, to a task.

If a user interface is evaluated only after the software has been made functional during product development, considerable effort would have been be wasted, should it be found at this late stage that the interface does not behave like a typical user would wish. Finding the right design solution can be harder than expected. A user interface design cannot simply be derived from functional requirements. Qualitative considerations have to be taken into account, such as findability, consistency in behaviour or user-friendly terminology.

User-centered product development

For these and other reasons many companies that develop products nowadays create interaction designs or prototypes to be evaluated and refined with the help of stakeholders in iterative processes [1, 2]. In addition to lab users, these stakeholders include domain experts, market specialists and development departments. To iteratively evaluate a product at an early stage, usability testing [1, 2] is often performed (for more details, see the info box).

Optimizing the user interface to navigate the measurement results

In our application case, optimal operability was always at the center. User-centered approaches enabled us to achieve substantial structural improvements in addition to smaller optimizations of many details.

full-screen

Fig. 1 Simplest structure / specialization (left) and most complex structure / generalization (right): Exemplary structures are compared using the same number of samples. Depending on the instrument type and application, a short and simple list of samples and measured values can be sufficient (left). Also depending on the instrument type and application, a flexible search system is required and measurement values can be further calculated into statistics and specific results (right).

Faster navigation through the measurement data

In addition to the generally useful performance features that were added, such as configurable screen views as well as storable and re-usable searches, the approach to the generalization of the measurement data is particularly interesting. During product development, particular effort was put into allowing the navigation depth of the standard view to be reduced in order to increase efficiency and/or user friendliness. This was achieved by introducing refined presentation rules and a unique configuration. Users can now determine for themselves how they want to balance navigation speed and displayed information abundance, allowing them to take into account the application area and personal preferences (Fig. 1).

Better orientation in the measurement data

Another interesting observation made with early prototypes is that users sometimes lost sight of where they were positioned in the navigational structure.The problem was not so much down to the terms selected for the menu items but probably more due to the fact that many interconnecting, net-like links were enabled whereas the basic navigation system was purely hierarchical. It is therefore possible that a breach in the direction of navigational movement was experienced or that control elements originally designed for hierarchical navigation were not optimized for this other purpose. In the subsequently improved prototype, hardly any non-hierarchical links were allowed. After it was tested, the orientation problem was gone. Unfortunately, due to lack of comparability, this route to a solution cannot be regarded as universally valid (Fig. 2).

full-screen

Fig. 2 (A) Early design phase – Cross-linked and cyclic navigation structures were integrated into a hierarchical overall system. The illustration shows this as a foreign body in the direction of movement. (B) Final design phase – Harmonization towards an almost purely hierarchical navigation structure was put into place. Only by changing certain configuration options can some data objects be reached by alternative routes.

Significant optimizations thanks to early involvement of stakeholders

Decisive for the above-mentioned optimizations was, above all, the flexibility given to product development to change these fundamental properties at all. If the interaction design can be presented as a flowchart or, better still, be experienced via a simulation on an interactive prototype at an early stage, the need for improvements and how to implement these becomes apparent earlier.

It’s all down to teamwork

Thanks only to the entire product development team working together was it possible to enable the implementation of these user-centered procedures in our project. It includes the management, which set the key strategic priorities, the committed and attentive team members as well as the professional implementation of the system.

___________________________________________________________________________________________

Infobox

• Usability Engineering
  Usability engineering is a methodical approach for achieving user friendliness of products by defining, measuring and ensuring usability in the product development process [1, 2, 3].

• Usability and User Experience
  The term “usability” itself has been somewhat soberly defined as the result of effectiveness, efficiency and user satisfaction [4] but many more other evaluation criteria have been suggested [5]. Perhaps it is easier to comprehend that the quality of the product is measured in usability tests using appropriate metrics. The term “user experience” is currently used very often. This, however, covers all of a person’s perceptions and reactions that result from using a product, system or service [1].

• Interaction Design
  Interaction design is a targeted design approach aimed at developing the format and, in particular, the behavior of an interactive product or system for appropriate use. This is done by visualizing suggested solutions [1, 6, 7].

• Usability Tests
  In usability tests, test persons are observed while performing a task defined in advance by a test scenario which, in turn, is based on setting measurement criteria and measurement targets. In essence, the usability tests show how many, if any, users can successfully complete the steps of their task when using the application, typically without support [1, 3].

___________________________________________________________________________________________

Category: Laboratory Management | Usability

Literature:
[1] DIN EN ISO 9241-210 (2011) Prozess zur Gestaltung interaktiver Systeme
[2] Mayhew, D. (1999) The Usability Engineering Lifecycle, 1st, Morgan Kaufmann
[3] Nielsen, J. (1993) Usability Engineering, 1st, Morgan Kaufmann
[4] DIN EN ISO 9241-11 (2011) Anforderungen an die Gebrauchstauglichkeit
[5] DIN EN ISO 9241-110 (2011) Grundsätze der Dialoggestaltung
[6] Cooper, A., Reimann, R., Cronin, D. (2007). About Face 3: The Essentials of Interaction Design, 1st, Wiley
[7] Kim Goodwin (2009). Designing for the Digital Age: How to Create Human-Centered Products and Services, 1st, Wiley