# Tiered access

In the past, which elements of the UKB data a research project can access has been controlled by the use of "baskets", where a selection of particular Data-Fields is made, and then, once the basket is approved, access is granted to those particular Data-Fields.

For many older projects, which remain on the old-style Material Transfer Agreement (MTA), this will continue to be the way that access to data is determined.

For new applications, and those which have reached the point where they need to move onto the new MTA, access will instead be controlled by researchers selecting one of three "tiers", with different types of data being available at each tier, and with different costs associated with these as described [here](https://www.ukbiobank.ac.uk/enable-your-research/costs).

Each Data-Field on Showcase has a "Cost Tier" associated with it, indicating which methods of access are available for that Data-Field and what tier the application must be in order to access the Data-Field by each method. For example, for Data-Field 20158 the Cost Tier is shown below:

<figure><img src="/files/QMmoVWdakOm4CbtKJ8dS" alt=""><figcaption><p>Figure 1.2: The Cost Tier information for Data-Field 20158</p></figcaption></figure>

This Cost Tier is given in a coded form as: dN1 oN2 sN3, where each Ni is a number from 1 to 3 or the letter X. In this code:

* d refers to download from the RAP
* o refers to accessing data online on the RAP
* s refers to downloading data from Showcase, either in a main dataset, via the download utilities, or via the Data Portal.

The numbers give the minimum tier that a project must be in order to access that Data-Field via that method. So for example, d1 o1 s1 means that any Tier 1, Tier 2 or Tier 3 project can access that Data-Field, whereas dX o3 sX means that the data for the Data-Field cannot be downloaded from the RAP or using the Showcase download utilities, and is only available to Tier 3 projects online on the RAP.&#x20;

In the case of Data-Field 20158 given in Figure 1.2 above, the Cost Tier of d3 o2 s3 indicates that the DXA images can be viewed online on the RAP by Tier 2 or Tier 3 projects, but that only Tier 3 projects are permitted to download the data from the RAP or download the data using the Showcase download utilities (ukbfetch in this case).


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