In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: Patients were rated monthly by parents on the Aberrant Behavior Checklist ( ABC ) and the Conners ' Parent Rating Scale - Revised , and by a physician using the Children ' s Psychiatric Rating Scale and the Clinical Global Impressions scale .
### Output Text:
Patients were rated monthly by parents on the Aberrant Behavior Checklist ( ABC ) and the Conners ' Parent Rating Scale - Revised , and by a physician using the Children ' s Psychiatric Rating Scale and the Clinical Global Impressions scale . 