Open access journals have grown in leaps and bounds and will certainly continue to do so. With scholars and governments openly supporting open access to scientific research, it is obvious that momentum behind open access publishing is bound to pick up. Take for instances "Harvard University Council Memorandum on Journal Pricing" which was published in 2012 essentially stating that the institution can't afford to pay ever rising periodical subscription prices, and encourages its researchers and faculty members to publish on open access. Or look at two major government growth drivers of open access publishing: The US government is pushing to make freely available research results that have been entirely or partially funded with tax payer money (See: "White house delivers new open access policy"). The UK government and European Union commission are following similar steps (See: "Finch Report March 19th 2013"). In his paper "The Inevitability of Open Access" the Dean of IUPUI University Library Mr. David W. Lewis forecasts that Gold Open Access Journal Articles will account for 90% of all journal articles as soon as 2020 and more conservatively by 2025.
...Why is it hard to find them?
About 20% of Open Access Journals articles are easy to track down and research thanks to the Directory of Open Access Journals (DOAJ). Yet, the remaining 80% of articles or well over 7 million are out of sight and unresearchable as a whole. In other words, a researcher would have to pay a visit to over 8,000 websites one by one to perform his research. One of the main reasons why so many articles are out of reach is that there are thousands and thousands of open access journal publishers who follow their own formats and are incredibly passive or simply reluctant to provide their data to aggregators on a regular basis. There are also numerous subscription journals that have an embargo period after which they become open access, but this is really hard to track as such periods vary from one journal to another. Finally, there are the professional and corporate open access journals many of whom publish their articles online only (non downloadable) and without organizing them according to library standards. The later resulting in researchers having a hard time to research them. Not even Google Scholar has been able to provide acceptable visibility of the millions of open access articles.
The Global eJournal Library is the most complete discovery service of Open Access Journals articles with a scope of 7 million articles in all subject areas and intended to get to 10,000,000 in 2015. How do we do it? Short answer: people like you and us! We are the only company that employs professional individuals who visit open access journal publishers websites daily to manually gather Meta Data and organize it according to library standards. These "human web crawlers" search the publisher website inside out to find articles and their corresponding Meta Data, download links and full text links. In most cases, such information is not easily traceable at the publisher website. The result is that the Global eJournal Library reaches more journals and articles than any other solution in the world.
So...Why not to just focus on the 20% that is easily visible and forget about the rest?
20% of Open Access Journals articles are easily found and researchable on the web, why to bother at all about the remaining 80% if it is open access anyway and may not live up to the same standards of quality of closed access journals? This is a question that some librarians ask as they want to ensure that their libraries offer only quality information. The answer is two folds. Firstly, open access journals articles are accounting for one third of all journal articles, which means that they are already too big to be missed at a library. A library that is missing out on one third of scholarly research content is incomplete. Secondly, while in the past, the impact factor of open access journals was significantly behind that of closed access journals, that situation has changed altogether. Currently, impact factor of open access journals are closed access journals are similar in many fields and countries. Several studies have arrived at this conclusion: "Open access versus subscription journals: a comparison of scientific impact", "Scholarly impact of Open Access Journals". Regardless of the specifics, there is one thing that comes access as far as open access journals articles is concerned: they are already too big and important but it is hard or nearly impossible for researchers to easily research them as a whole.
Global eJournals Library