Tag: pubmed

A major part of the intrigue surrounding nootropics has to do with the fact that many of these compounds have not been largely studied. In effect, we are gambling with our neurochemistry in order to gain some benefit in our mental functions. But we are not without resources which can improve our chances of using nootropics safely & effectively. While the body of evidence behind nootropic agents is not large, it is growing, & will likely continue to grow with increasing rapidity as public interest in nootropics increases. Drawing upon this background of research can help us understand how nootropic agents work, in whom they work, & what the risks are. To this end, I will be launching a multi-part tutorial on how to understand & interpret clinical trials, designed for both novices & more advanced users. Topics we’ll cover include:

• Validity & bias
• Types of studies & hierarchy of evidence
• Reading results (graphs & tables)
• Methodology
• Basic biostatistics

How to access clinical research

First of all, clinical research is generally accessible by online databases through universities or hospitals. If you have access to some of these databases through your institution, such as Medline or Ebscohost, I highly recommend familiarizing yourself with them. For those without institutional database access, Pubmed offers a large open-access catalog of many journal articles. Google Scholar is another option for finding studies, but does not offer advanced search functions.

Here are some other tips when searching for journal articles:

• I would generally recommend limiting one’s search to full text articles, as abstracts do not often reveal the full story of a study.
• Searching by MeSH terms (analogous to tags for topics) usually provides more relevant results than a basic keyword search. This involves searching for a MeSH term, selecting it, then running the search.
• More recent results (preferably within the last 5 years) are preferable, as scientific research can move fast. Depending on the topic area, however, you might find yourself stretching your search to include up to 10 years.
• Be aware of the country of origin of the article, as standards for publication may vary.
• Authors who write many articles on the same topic may be biased &/or highly knowledgeable.

Structure of a journal article

So you have located a journal article of interest. Fortunately, every journal article generally follows a similar structure. This organisation is designed to present the details of the study in an intuitive order.

• The abstract is a short summary of study’s methods & results.
• The background section reviews the current state of understanding in the topic area of interest. The investigators conducting the study also explain what they are trying to show.
• In the methods portion, key details of how the study works are defined:
  • Endpoints or outcomes are what is being measured, such as performance on a cognitive test
  • Experimental variables are what is being tested, such as the study drug & the control against which it is compared (placebo or standard treatment)
  • The type of individuals the investigators wanted to analyse in their study as test subjects
  • The allocation or assignment of enrolled individuals to either treatment groups (who receive the study drug) or control groups is typically visualized in a flowchart
  • Statistical tests used to analyse the data
• The results section is where authors list their findings only (without interpretation). These include:
  • Baseline characteristics– a description of the final sample. Most often, this is summarized in table labelled as Table 1. When reading this section, think about the age, race, geography, & health status of the sample, & whether they are similar to you.
  • Outcomes– how did people who took the drug do in comparison to those who took the control? These data will be presented in tables, charts, graphs, & text.
• Considered to be the most important section, the discussion area is where investigators interpret the results- what they mean, whether they are significant, where there could be error, the weaknesses of their study, & areas for further research. What is stated in this section can sometimes be highly contentious.

Some tips for reading an article:

• The background section is not usually necessary unless if the topic area is new to the reader- if you are extensively researching a drug by reading multiple articles, you will find that many of their background sections are similar. However, if you don’t understand what’s covered in the background section, bring yourself up to speed with other resources such as Wikipedia.
• Some prefer to read the abstract first to obtain a rapid summary of the study, then the discussion second for a detailed look at how the authors felt about the findings.
• Always compare the raw numbers from the results section against the authors’ interpretation in the discussion section. Never take what the authors state at face value. Do the numbers actually show what they claim is happening?
• Yes, the word «data» is plural.
• I personally prefer to print out the pdf article & write comments on the hard copy as I read.
• It’s not uncommon to read the same article several times. These subjects are quite advanced, & many details are important.
• Check the articles cited in the bibliography for other studies that might be related to your topic.

Summary

In review, using clinical data can provide a powerful edge when making decisions about nootropics. The informed nootropic user is better able to discern which nootropics are safe & effective.

• Clinical research is accessible within databases which are offered through institutions. The general public can access some research through resources such as Pubmed or Google Scholar.
• All journal articles follow the same general format consisting of an abstract, background, methods, results, & discussion sections. Knowing where to find what information you need within an article can make reading articles faster.