9. Sample Attributes

9.1. What are Sample Attributes?

Sample attributes are largely the same as project attributes, but they are attached to individual samples within the project rather than to the project as a whole. Where a project attribute records something about the entire case (for example, Diagnostic Status), a sample attribute records something about a specific sample in the project (for example, that sample's affected status or a quality metric for their sequencing data).

Many of these values are populated automatically when case data is loaded, and they appear as columns on the Samples page.

9.2. Public and Private Sample Attributes

As with project attributes, sample attributes can be public or private. Public sample attributes can be imported into other projects and are visible at the collection level, which makes them useful for comparing the same measurement across every individual in a cohort. Private sample attributes exist only in the project where they were created. The recommendation to create shared (public) attributes in a dedicated attributes project or template, rather than ad hoc in individual projects, applies to sample attributes just as it does to project attributes — see Where Should Project Attributes Be Created.

9.3. Viewing and Editing Sample Attributes

Sample attributes are displayed as columns on the Samples page in both projects and collections. Use the Edit Columns button to choose which sample attributes are shown. To edit a value, click the value in the table (provided the attribute is editable and you have permission). Because the Samples page in a collection aggregates samples from every constituent project, displaying a sample attribute as a column there is an efficient way to review that value across the whole cohort at once.

9.4. Attribute Types

Sample attributes support the same range of types and options as project attributes — text (optionally with predefined values), number, and time, and they may be longitudinal (holding multiple time-stamped values, useful for measurements that change over time). For full detail on attribute types, predefined values, importing, and pinning, see Project Attributes, which describes the same mechanics in depth.