Your goal is to extract structured information from the user's input that matches the form described below. When extracting information please make sure it matches the type information exactly. Do not add any attributes that do not appear in the schema shown below.

```TypeScript

 { // Information on the clinical trial characteristics from the abstract
 conditions: string // The condition or disease being treated in the clinical trial
 drug_or_intervention: string // The drug or intervention used in the clinical trial
}
```


Please output the extracted information in JSON format. Do not output anything except for the extracted information. Do not add any clarifying information. Do not add any fields that are not in the schema. If the text contains attributes that do not appear in the schema, please ignore them. All output must be in JSON format and follow the schema specified above. Wrap the JSON in <json> tags.



Input:Effects of singing classes on pulmonary function and quality of life of COPD patients.  This study aimed to investigate the effects of weekly singing classes on pulmonary function parameters and quality of life (QoL) of COPD patients. Forty-three patients were randomized to weekly classes of singing practice, or handcraft work. They performed spirometry and completed maximal respiratory pressure measurements, evaluations of dyspnea, and the Saint George's Respiratory Questionnaire, before and after 24 training classes. A functional evaluation, immediately after 10 minutes of singing practice, was also performed at the end of the study. Fifteen subjects completed the study in each group. In comparison to controls the singing group exhibited transitory elevations on the dyspnea Borg scale (p = 0.02), and inspiratory capacity (p = 0.01), and decreases of expiratory reserve volume (p = 0.03), just after a short session of singing. There was a significant difference on changes of maximal expiratory pressures in the comparison between groups at the end of training. While the control group showed deterioration of maximal expiratory pressure, the singing group exhibited a small improvement (p = 0.05). Both groups showed significant improvements of QoL in within group comparisons. We have concluded that singing classes are a well tolerated activity for selected subjects with COPD. Regular practice of singing may improve QoL, and preserve the maximal expiratory pressure of these patients. Output:
{'conditions': 'Chronic Obstructive Pulmonary Disease', 'interventions': 'Other: Singing practice|Other: Singing classes|Other: Hand craft classes'}