by Vannesa Mosher and Steven Weintraub
In a online survey of the usability community, Whitney Quesenbery asked for opinions about two approaches to implementing a drop-down list box to allow the user to select a navigation option:
- A drop-down list box that requires the user to submit his/her selection via a Go button (or similar)
- A drop-down list box that automatically submits the selection immediately after it’s made
As you may expect, there is no single answer from the 30 respondents. A quick tour of some of today’s Web sites confirms the lack of a consensus on whether to use Go buttons with navigational drop-down lists. But arguments were compelling on both sides: those in favor of the Go button focused on error prevention, recovery, and accessibility for the visually impaired, and those against the use of Go cited issues relating to frequency and efficiency of use.
Several people working with blind users commented on problems both with screen readers and for those using keyboards. For example, one cited a usability test by Sarah Miller at the Open University. Sarah found drop-down lists without Go buttons were confusing because while the user had to inspect every item in the list, the action of reading an item meant that it was selected. She added that the user chose to use the keyboard instead of a mouse to scroll through the options to view (or hear) them: the first option was automatically selected—the user never got past the first item in the list.
A few respondents also commented that auto-submit drop-down menus may be counter productive when interpreted by screen reader software (often used by the visually impaired). It seems that the software automatically selects the first item in the menu when the user opens it using either a mouse or keyboard.
One strong voice for using a Go button was Larry Marinem. Larry suggested that users do not expect the drop-down list to be a navigation device. He stated that there are certain things that users expect a control to do, and sometimes it is common for designers to over-automate a step of the task by changing the normal expected behavior of a control. Drop-down lists are expected to display the selected object, not go somewhere. With drop-down lists, it’s not uncommon for users to mis-select something; the users are surprised when this type of control launches them off somewhere and more so when it launches them into a mis-selected area. Larry added that reducing the number of clicks does not make a site more usable; giving the users appropriate control of their navigation does.
Despite this strong argument, Dave Perkins and Ginny Redish presented usability evidence in favor of automatic actions.
Dave Perkins stated that employees at his company viewed the Go button as annoying. Users would select an option and nothing happened. Selecting the Go button was something that needed to be learned.
Ginny Redish conducted a usability test of a site that made extensive use of drop-down lists with Go buttons. The primary audiences were parents and health professionals, spanning the entire range of Web experience. Ginny reported that the Go button confused everyone, no matter what level of Web experience. Users assumed that they had made a selection after they clicked on their target item and saw no reason to have to also click a Go button. Even after several tasks, the users were still forgetting that they had to click the Go button. Based on Ginny’s test results, a recommendation of no Go buttons was implemented. Ginny re-tested the new (without Go buttons) version and stated that everyone was successfully using the drop-down lists.
Ginny notes that no one said “I expected to see a Go button” or looked for one.
What’s Best for Users
If you find yourself in the difficult situation of not knowing which approach to take or having to defend your choice to your client or supervisor, test the design with intended users: observe their behaviors and expectations, likes and dislikes. Consider the context of use.
Drop-down list box without Go button
If users are dedicated and frequent visitors to a site, users may enjoy the productivity gains of an automatic action on select. Some respondents indicated that a standalone drop-down list box without an accompanying Go button is more intuitive and efficient than one with a Go button, especially when the user works with the list frequently and is familiar with its auto-submit functionality. The STC Web site provides a good example of this instance of use:
Figure 1. Drop-down list box without Go button.
Drop-down list box with Go button
If users are casual or occasional in visiting a site and lists are long, error-free performance seems unlikely; a Go button accompanying a drop-down list box may be necessary. Figure 2 shows an example of a drop-down list box with Go button. Although the frequency of use may be high, the consequences of mis-selection may be relatively low.
Figure 2. Drop-down list box with Go button.