The purpose of an HTA is to create a hierarchy of steps that must be followed to complete a high-level activity. Breaking down a business into distinct milestones and having plans to complete those milestones is key to Hierarchical Task Analysis. Create a plan that describes how a hierarchical activity analysis combines sub-activities that allow users to achieve a specific goal and all the conditions under which sub-activities must correspond to sub-tasks that allow users to achieve a specific goal.

That a task is performed only under certain circumstances is information about the dynamic aspect of the analysis; plan that the user will have to complete. The analysis begins with identifying the main task that the user performs. At the end of the task analysis, the analyst understands all the different tasks that users can perform to achieve their goals, the different tasks that users can perform to achieve their goals and the nature of such tasks.

The information obtained from performance analysis can then be used for many purposes such as recruitment and training of personnel, development of tools or equipment, development of procedures (e.g. development of checklists or decision support systems) and automation. An activity analysis diagram or Hierarchical Task Analysis is often the product of an activity analysis; An Hierarchical Task Analysis can inform others about the process users are following and a starting point for further evaluation. Hierarchical activity analyzes can be used as a basis for subsequent analyzes such as SHERPA error analysis and/or critical path analysis. HTAs provide information about higher- and lower-level user goals, plans—the conditions required to perform specific actions and operations—and what people do as part of an activity.

Observational methods can provide information for hierarchical analysis of existing system activity, while surveys and similar qualitative approaches can help you understand how users think about the activity when designing new systems, ensuring that the proposed approach is consistent with existing user thinking patterns. The combination of different approaches to the description of user interaction provides a broad and deep understanding of the activity. A more subtle workflow approach may be more appropriate for analyzing tasks performed in particularly complex contexts. Critical performance review, for example, is an analysis of human performance requirements that, if not performed in accordance with system requirements, may adversely affect the system’s cost, reliability, efficiency, effectiveness, or safety.

In hierarchical analysis, the instruction designer breaks down the task from top to bottom, thereby showing the hierarchical relationship between tasks, and then the instruction is built from the bottom up.

Share This