You do not need to provide the poster prior to presentation (ADNI Data and Publications Committee review is only required for manuscripts for peer review and publication). It'd be great if you can include "For the Alzheimer's Disease Neuroimaging Initiative" to acknowledge ADNI's contributions in your byline. And here is the link for other acknowledgment language - feel free to include whatever seems appropriate and can fit: http://adni.loni.usc.edu/wp-content/uploads/how_to_apply/ADNI_Manuscript_Citations.pdf.