When you define group mappings based on specialty, body part, and patient location, each mapping is assigned a rule number. Rule numbers come into play when a study description matches two or more wildcard source patterns. The source pattern with the lowest number is the one whose mapping is applied to the study.
For example, the site has one specialty mapping rule for chest studies based on source pattern %CHEST%, and another for pediatric studies based on %-PED%. A study with description CHEST-PED matches both of these rules. To ensure that all pediatric studies are grouped under that specialty, the Pediatric mapping is assigned a lower rule number. The chest grouping therefore includes pediatric chest studies.
| Study description | Radiology specialty | Specialty mapping | Rule |
|---|---|---|---|
| CHEST-PED | Pediatrics | %-PED% | 10 |
| CHEST SINGLE VIEW | Chest | %CHEST% | 20 |
 | Tip: When you establish the initial rule numbers, leave numbers open. For example, create your rule numbers in increments of 10 (110, 120, 130, and so on). Then, as you refine your mappings, or if new study descriptions are created at the site, rule numbers remain to assign to the new items. |
Here is more extended example of rule number usage.
| Rule number | Source pattern | Map all matching descriptions to |
|---|---|---|
| 10 | %NM% | NM |
| 20 | %VITRUS% | GASTRO |
| 30 | %US% | US |
| 40 | %GAS% | GASTRO |
| 50 | %CT%HEAD% | CT_HEAD |
| 60 | %CT% | CT_OTHER |
| 1000000 | % | BODY (all other rules fail) |