I would be cautious using WebMD for scholarly pursuits as the site is commercial in nature. If there is any doubt about this, look at the advertisements prominently featured on their site.
For alternatives, consider some of our allied health databases:
- Health and Wellness
- Health Source - Consumer Edition
- Health Source: Nursing/Academic Edition
- CINAHL - of the four, this is the most scholarly
To answer your question about discerning the credibilty of a source take a look at our guide about evaluating information. There are six criteria to consider:
- Authority/Credibility
- Accuracy
- Scope/Relevance
- Currency/Date
- Objectivity/Bias/Reliability
- Style/Functionality
Matt Bejune
Coordinator of Library Reference and Instruction