MedlinePlus and PubMed: reading the research yourself

The National Library of Medicine sits on the National Institutes of Health campus in Bethesda, Maryland. It was founded in 1836 and calls itself the world's largest biomedical library. It keeps a vast print collection and produces electronic information resources that are searched billions of times a year.

Two of those resources are the ones you are most likely to meet. MedlinePlus and PubMed.

They feel similar from the outside. They are not. Choosing the wrong one is the most common reason people come away from a search feeling stupid, when in fact they simply walked through the wrong door.

MedlinePlus describes itself as an online health information resource for patients and their families and friends. That is not a marketing line. It shapes everything about the site.

It is free, and it is free of advertising. The content is available in English and Spanish.

The site is organized into a handful of sections. Health topics, which are overview pages on conditions and concerns. Drugs and supplements. Genetics. Medical tests. And a medical encyclopedia.

That last group is quietly useful during cancer treatment. When a discharge sheet lists a lab test you have never heard of, or a new prescription arrives with a name you cannot pronounce, MedlinePlus is a reasonable first stop for a plain description.

MedlinePlus also points outward. Its clinical trials page, for example, describes clinical trials as research studies that test how well new medical approaches work in people, and links to ClinicalTrials.gov for searching and to its glossary for terminology.

PubMed comes from the same library, developed and maintained by the National Center for Biotechnology Information. It is a free resource supporting the search and retrieval of biomedical and life sciences literature, with the stated aim of improving health.

Its scale is the thing to understand. PubMed contains more than 40 million citations and abstracts of biomedical literature.

Notice the two words: citations and abstracts. A citation is the article's identifying information. An abstract is the authors' own short summary. PubMed does not include the complete journal articles in its own database. It frequently offers links to the full text when that is available from another source, such as the publisher's website or PubMed Central.

So a PubMed search can end in three ways. You find a free full article. You find an abstract with a paywall behind it. Or you find a citation and very little else.

MedlinePlus can give you a calm, ad-free explanation of a term, a test, a drug, or a condition, in two languages, at no cost. When a family member asks what something means and you do not want to send them into the open internet, this is a safe place to send them.

PubMed can tell you whether research on a question exists at all. If you have been told something is experimental, or you have heard a claim about a supplement, PubMed will show you whether there is published literature behind it and roughly how much.

PubMed can also give your appointment a spine. Bringing one specific paper, or even one specific title, changes the conversation from "I read something online" to "I read this, does it apply to me."

And both can be used in small doses. You are allowed to look up one word and stop.

Neither one knows anything about you. They hold no records, no scans, no pathology.

PubMed does not judge quality. It indexes what was published, including small studies, early findings, and papers later contradicted. The tool does not rank the literature by how much you should trust it.

PubMed also cannot hand you every full paper. Access depends on publishers and on what is deposited in PubMed Central.

MedlinePlus, for its part, is general by design. It is written for a wide audience, so it will not carry the detail of a subtype, a specific regimen, or a decision that hinges on your particular pathology.

And neither site can weigh a decision. A page or an abstract cannot tell you whether a treatment is right for your body, your goals, and your other conditions.

Start with MedlinePlus. Get the plain-language version of the topic in your head first. It makes anything you read afterward far less frightening.

Only move to PubMed with a specific question, and set a limit before you start. One question, a short block of time.

When you find something that matters, do not try to settle it alone. Save the title, write down what you want to ask, and take it to the person who knows your case. That is where a search should end.