How Accessible is Psychology Data?

In a slightly depressing new paper, two researchers describe how they tried to get access to the data behind 111 of the most cited psychology and psychiatry papers published in the past decade. The researchers, Tom E. Hardwicke and John P. A. Ioannidis of Stanford, wanted to place the data into a 'Data Ark' to ensure its continued preservation for science. Unfortunately, in most cases, the data was not made available. The paper is called Populating the Data Ark and it's out now in PLoS ONE. Hardwicke and Ioannidis wrote to the authors of each of the highly-cited articles, explaining the idea behind the Data Ark and requesting the raw data - including the option to give the data to the researchers but with restrictions on who could access it. In about 40% of cases, Hardwicke and Ioannidis received no meaningful response whatsoever. Another 30% of authors declined to share the data in any way. Only 14% of the datasets were made available with no restrictions on who could access them (either made available in Data Ark, or already freely available.)