Department of the Interior Bison fenced in angle bracketsOpen data, design, & development at the Office of Natural Resources Revenue

Tree testing using a clickable prototype

December 18, 2020

As we’ve approached the redesign of, we’ve done several rounds of user testing, including open and closed card sorting. Card sorting helped us determine the categories and subcategories that users expect to see on the website. We wanted to further confirm that we were placing the subcategories into the correct main categories and that users would be able to find the needed information, so we turned to tree testing. Tree testing was a new type of user research to our program analysts so we read a few articles to get up to speed.

Getting started

Our first step in the process was to figure out how to use our existing or free software to conduct the tree testing. After some investigation, our UX expert determined that a clickable prototype would serve our needs. We used the software that she already uses for prototyping so she could quickly create the testing materials. You could use any software that allows clickable interfaces to do the same thing.

Planning the study

In planning the study, our goals were to validate the structure that came out of tree testing, determine whether users could find items that were hard to categorize in the card sort, and determine if we needed to change any category labels. We wanted to have common tasks that would direct users to each main category so we could really get a feel for how users search for information on our site. We limited the list to 10 tasks, since users learn the categories quickly in tree testing. We dug into past research to help us determine the user tasks and had our teammates peer review to make sure that our tasks were realistic and encompassed common user needs. Our UX expert also created 3 different versions of the prototype with the tasks randomly organized in different orders to remove some bias in the task order.

Version 1 of the clickable prototype

Clickable prototype, version 1 with numbered task on the left top side and the main categories on the right side

We also decided to show a wireframe of the homepage using the categories after the tree test tasks, so users could see where we were headed with the site using the categories and get some feedback on the categories in context.

While we were planning the study, we concurrently recruited as many external (capped at 9) and industry users as possible to survey a wide user audience.

Conducting the study

We scheduled 30-minute moderated virtual interview sessions with all 11 participants – 4 external and 7 internal. We had one moderator and tried to have two notetakers since this was a new way of doing user research for our team. After the initial explanation we had them work through all tasks and talk through their category decisions.

We initially tried to record their responses right in a spreadsheet to make it easier to analyze our findings, but in the first interview we found that it was too difficult to work quickly within the spreadsheet and we decided to use a document to take our notes instead. Despite it being our first time conducting tree testing using this process, we were able to easily communicate the instructions to the participants.

Spreadsheet notes: User interview notes in a spreadsheet Document notes: User interview notes in a word document


After summarizing the findings, we used Sankey diagrams to show how users navigated from the task to the subcategory. The visualization helped to illustrate which tasks were straightforward and which ones were confusing. We had several tasks that made us feel confident that we had the right structure in place, including leading participants to report production, find contacts, file appeals, and make rent payments. The Sankey diagram below illustrates how all participants agreed on where to report production.

Sankey diagram of user task 3

Then we had several tasks where participant responses diverged significantly. These tasks included how to set up a new team member, how to find information on the site, and how to find help with ONRR reporting and paying systems. The Sankey diagram below shows that participants were divided on whether to go to the Getting Started category or Reporting Resources main categories to add a new team member as a contact. The responses further diverged within the subcategories as some participants were looking for a specific form and some thought it would be in Getting Started. Our solution to this and similar issues will be to include the needed resource in more than one category.

Sankey diagram of user task 7

We also made some major changes to the categories. We found that participants had to think about where to look for the regulation/valuation task and thought that valuation should be a separate category, so we added one for that. Participants unfamiliar with Indian reporting would navigate to the Indian Resources category for anything Indian related so we will cross post Indian pricing, regulations, and codes to the Indian Resources category. Participants were also divided on whether to look for similar information in the Reporting or Reporting Resources category. We determined that it would be better to use only the Reporting category and add the Reporting Resources as sub-categories to each reporting section.

Overall, participants wanted more information about how the entire reporting and paying process works, especially those that are newer to their positions or need information on how to report and pay on more complex leases and agreements. People from within our agency who field contacts from industry also expressed this need, so we will be creating a visual showing the process.

To better illustrate the changes to the main and subcategories that we are proposing, the first table below shows the original tested categories and the second table shows the new proposed categories.

Tested categories

Getting Started Reporting Reporting Resources Paying Enforcement & Appeals Indian Resources About ONRR
New Reporter Checklists Production Reference Lists & Codes Rental Payments Compliance Authorities Cooperative Agreements Press Releases
System Access Royalty Reporting Contacts Royalty Payments Appeals Allottee Assistance Leadership
Solid Minerals Handbooks Late Payment Interest Bankruptcies Federal Indian Minerals Office Office Locations
Geothermal Forms Treasury Referrals Civil Penalties Indian Energy Service Center Employment
Pricing Tribal Assistance Committees
Unbundling Tribal Consultation Testimony
Reporter Letters Freedom of Information Act (FOIA)
Regulations Anti-Harassment Program
Training Videos Contact Us

Categories after testing

Getting Started Reporting Guidance & References Paying Enforcement & Appeals Indian Resources About ONRR
How Leasing Works Oil & Gas Production
- File Reports
- Forms
- References
-Reporter Setup
- Contacts
Valuation & Pricing Payment Options Compliance Authorities Assistance Public Affairs
New Reporter Setup Oil & Gas Revenue
- File Reports
- Forms
- References
-Reporter Setup
- Contacts
Reference Lists & Codes Jointly-Owned Lease Payments Appeals Cooperative Agreements Organization & Leadership
System Access Solid Minerals
- File Reports
- Forms
- References
-Reporter Setup
- Contacts
Reporter Training Late Payment Interest Bankruptcies Indian Guidance & References Office Locations
Reporter Training Geothermal
- File Reports
- Forms
- References
-Reporter Setup
- Contacts
Handbooks Unpaid Debt Civil Penalties Indian Payments Employment
Forms Contacts Cooperative Agreements Committees
Reporter Letters Testimony
Rules & Regulations Freedom of Information Act
Anti-Harassment Program
Contact Us

Lessons learned

The tree test was a valuable way to dig into our site reorganization and test our hypotheses and assumptions. We tried again to take notes in a spreadsheet rather than a document and it didn’t work out very well. We tried this about a year ago for user interviews with the same result, so we should avoid doing that in the future to save ourselves from having to duplicate the notes we take. We also found it was helpful to have more than one person observe and take notes because participants moved through the tasks very quickly and it was sometimes hard to record their responses. The moderator learned to ask questions and slow them down to give the note takers more time.

We also learned how quickly participants move through a tree study and learn the categories. None of us had ever observed one live because we had always used remote tools before and it really underscored the importance of having few tasks and randomizing the order. Some of our sessions only lasted 15 minutes even after troubleshooting technical issues getting started.

We also learned how to simplify some of our main categories in our site organization and to reorganize some of the sections where we needed more feedback.

Our next step is to use the content audit to place everything into the new categories, and refine the current subcategories to match the website content. We are also wireframing at the same time to make sure that we have content where we want it and a home for every piece of content. Finally, we will run another round of user interviews after we finish refining the subcategories to confirm that we’ve properly organized the content.

Note : Reference in this blog to any specific commercial product, process, or service, is for the information and convenience of the public, and does not constitute endorsement, recommendation, or favoring by the Department of the Interior.

Lindsay Goldstein profile image

Lindsay Goldstein: Digital Services Specialist at the Office of Natural Resources Revenue.

Shannon McHarg profile image

Shannon McHarg: User Experience Designer at the Office of Natural Resources Revenue.