Where is the description file for ADHD-200 data:
where could I download the description files?

I do not know who are healthy people and who are patients.
Also I still do not know the experiment designs such as TR, TE and the scan time.

Moreover, why some subjects contain two resting state functional data and some others only contain one functional data? Are all the data acquired under the same conditions (such as length of the scan, TR and Eyes closed or open)?

Hi,I met the same questions too.

I can find some of the MRI scan parameters in the web site " http://fcon_1000.projects.nitrc.org/indi... ", but some sites' scan parameters  are not available.
As for the labels of patients and healthy controls,you can download the pre-processed data (zip-file) from the dataset to find the information.
I think it's a time consuming job to reorganize the raw data and preprocessing by yourself instead of using the already pre-processed data available online.
If you can find all the sites' scan parameters of fMRI and 3DT1 , I would be very grateful to be shared with.