| Code | Display | Definition |
| Rcm | Recommendation | The METRIC is a recommendation for the containment tree entries defined in ./pm:Relation/@Entries |
| PS | Presetting | Presetting. This METRIC is a presetting for the containment tree entries defined in ./pm:Relation/@Entries. |
| SST | Set of summary statistics | The METRIC is part of a set of summary statistics for a sample where other METRICs that belong to the summary statistics are defined in ./pm:Relation/@Entries. |
| ECE | Effect on containment tree entries | When changed, the METRIC has an effect on the containment tree entries defined in ./pm:Relation/@Entries. If Kind is ECE, ./pm:Relation/pm:Code SHOULD be set to classify the effect. |
| DCE | Derived from containment tree entries | The METRIC is derived from the containment tree entries defined in ./pm:Relation/@Entries. If Kind is DCE, ./pm:Relation/pm:Code MAY be set to classify the form of derivation. |
| Oth | Other | Relation is specified by other means, e.g., ./pm:Relation/pm:Code or extension element. |