The article reviewed here is a brief report – original research by Mark Boschen who is based at the School of Psychology, Griffith University, Southport, Australia.
The idea is a neat one and fairly easy to replicate – as it involves looking at research articles on Medline. Indeed Boschen has submitted or published a number of other articles using this approach. Boschen cites various pieces of research which suggest a trend towards a greater coverage of anxiety disorders in the psychiatric literature.
Boschen selects a number of terms related to anxiety including agoraphobia, OCD, acute stress disorder and of course PTSD before entering these as search queries into the medline database. The number of articles obtained each year are counted and also retrieved to ensure they are relevant. Boschen found that there was a trend to a linear increase in the number of articles produced per year (linear regression analysis showed r = 0.97 with p < 0.001). PTSD articles increased from 16.3% of the total number of ‘anxiety articles’ to 38% in 2001-2005.
However there are a few cautions in interpreting these results. I’ve been interested in this area myself and have been involved in some preliminary research. The first point is that the software for accessing Medline was not mentioned. There are numerous interfaces for searching the Medline database and the software itself is important in determining the results. It is difficult to anticipate how the different interfaces might bias the results.
The next point is that a small number of anxiety disorders are explicitly mentioned and these do not include terms such as neurasthenia, dissociative disorder or specific phobias such as acrophobia or arachnophobia. Thus it is more than likely that the proportion of articles represented by PTSD was overestimated.
Another point is that there are numerous publications that are not cited in the Index Medicus which forms the basis for the medline database. Thus there is a substantial amount of literature on PTSD and anxiety disorders which will not have been identified from this search. If there is a trend towards increasing PTSD research in established journals then perhaps research bucking this trend will find a home elsewhere and PTSD research will have been overestimated as a proportion!
A more tricky issue is that of nomenclature. Thus within the MeSH headings of medline abstracts – tags which help to identify articles more easily – there are occasional changes in categorisation. This means that PTSD may have been ‘filed’ with anxiety disorders initially. There is no mention in the paper of the year in which PTSD was created as a MeSH heading. This means that PTSD research could have been underestimated in the earlier years examined in the study. It would have been nice to see some graphs of the other anxiety disorders mentioned to (superficially) examine some of these issues.
Nonetheless, it is difficult to argue with the conclusion that the number of PTSD studies has increased. Regardless of whether all articles are included, the results most likely represent a trend in the overall literature. Boschen has clearly put a lot of hard work into this study and done so single-handedly and the results are valuable.
What is remarkable is that if these trends continue, by 2010 there will be over 400 articles per year. This is an exciting area for research as it points to the overall process of doing research from a strategic perspective.
The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.