The HOME Cell
The i2b2 Health Outcomes Monitoring and Evaluation (HOME) Cell allows users to evaluate health outcomes over time without direct programming. The HOME Cell uses the existing i2b2 framework (queries, ontologies, data) and drag-and-drop software components to allow users to model a vast number of exposures (including interventions such as medications or tests) against an equally large number of outcomes accounting for complex temporal relationships and stratified by sub-populations. The process typically follows the following 8 steps.
- Define a base query using the i2b2 Query Tool (not the HOME Cell). This query needs to include all possible patients but needs to include everyone who will ever be included in a denominator group. It should be the smallest possible number to improve query efficiency. For example, a base query of everyone who has ever had diabetes could be used to support all HOME Cell queries related to patients with diabetes.
- Open the i2b2 HOME Cell.
- Apply the base query to the new HOME Cell query within the denominator tab.
- Use Constraints (Age, Occurrence, Value) to define the denominator population.
- Use Constraints to define the numerator population (people from the denominator with the target outcome).
- Specify (optionally) sub-populations (strata) to evaluate the target outcomes which are, like the base query, a previously created i2b2 Query Tool.
- Define the reference interval and date range.
- Execute the query!
After a HOME Cell is successfully completed, the completed data can be found in the data tab which can be exported as a spreadsheet or copied. The data will also be presented in a graphical format in the Graph tab, which can easily be exported as a static file image. Each step is described in more detail within this section.