From PubMed:

PubMed comprises over 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. PubMed citations and abstracts include the fields of biomedicine and health, covering portions of the life sciences, behavioral sciences, chemical sciences, and bioengineering.

Anyone can automatize searches with the Entrez programming utilities from any of the databases of the National Center for Biotechnology Information (NCBI). PubMed is one of the databases so I downloaded the amount of citations in the title or abstract of some terms related to refractive surgery from the year 2000 to 2014 (up to 21 November) and I graphed them.

First a timeline with all the terms:


There are much more articles for the terms "Lasik",  "PRK" and "Refractive surgery" than from the others. That makes the other terms relative differences harder to see. To solve that problem we can choose the same graphic without the three terms with highest number of articles:



Or we can do one graph for each term, like in the last graphic of the last post. I will do it this time with the y scales different, we can see the trends for each term easily but it´s harder to compare between them:



We can see that ReLEx, Wavefront guided, phakic IOL and multifocal IOL show an increasing trend, Lasik articles are decreasing after the 2005 peak although in absolute numbers still the highest and PRK shows also a decreasing trend in the number of articles with that term in the title or abstract. Remember that for 2014 the articles count is until 21 November and might end the year with some more.

You can find the code to replicate the graphics in R here. They might look different for 2014 if you execute it on a later date with updated data for 2014.


The website Vision problems in the U.S. from Prevent Blindness America has a very nice map of the U.S. where you can click on a state and will give you the estimated number of cases by vision problem for people over 40, over 50 in the case of age related macular degeneration (AMD), for 2010. By clicking on the top menu on each of the vision problems you get a graphic by age category, sex and race of the estimated prevalence rate for that vision problem, also there are submenus with tables for each visual problem.

In the news and resources tab you can download the data and that is what I did to play a bit with it. Although for many of the graphics I will do, a linechart is a better choice, I will make some barcharts without specifying state or race. So the barcharts are for all the U.S. and all the races.

I will start with a barchart of the estimate prevalence rate for all the population in the U.S. by visual problem:

Very colorful. Now lets get more details with a barchart of the estimated prevalence rate for every visual problem by age category:


You may have notice that diabetic retinopathy is not in that barchart, the reason is that it has another age category ranges. The ranges are larger so there are less categories, here is the graphic:



Now the same for sex with a slightly different look:


 I will make now one for the prevalence rate for every vision problem by sex and age category, with this style we can put all vision problems since every chart has it´s own x scale:



 You can find the R code to get the data, arrange it and make the plots here