The best way to find the EXAMDATE

[kostas ioannou]

Hello everyone,

I was looking for the best way to find the EXAMDATE for the subjects that does no exist.

Firstly, I thought to use the USERDATE instead. What do you think about that? I read, at ADNI's site, that the USERDATE may be quite different from the EXAMDATE but in cases that both of them have been recorded I see that the difference is usually some months or some days. So I thought that the USERDATE could be used instead of the EXAMDATE for the cases that the last has not been recorded. However I also read that  best way to extract the EXAMDATE is by using the RID, the PHASE and the VISCODE and VIDCODE2 from the REGISTRY.csv! Which of the two ways would you recommend?  And a second question, as I am not sure if I have understood that well, what is the difference between VISCODE and VISCODE2?  Thank you in advance !

[Danielle J Harvey]

Hi there,

 

REGISTRY is the best place to find the EXAMDATE. My understanding of USERDATE is that it captures when changes have been made to the data…in some phases of ADNI, the first USERDATE might reflect when the data were first entered for that participant and visit, but I don’t think that is always the case. For that reason, the Clinical Core recommends using EXAMDATE from REGISTRY.csv (it should be fine to merge using RID and VISCODE2).

 

VISCODE is the visit code used in the tracking system. In ADNI-1, those codes were easily interpretable, but starting in ADNI-GO, they became less clear. To have more meaningful codes that researchers could follow, the Clinical Core created VISCODE2 and incorporated it into the various files, translating the VISCODE into the more meaningful month visit for each participant.

 

Hope this helps!

Danielle

--
You received this message because you are subscribed to the Google Groups "Alzheimer's Disease Neuroimaging Initiative (ADNI) Data" group.
To unsubscribe from this group and stop receiving emails from it, send an email to adni-data+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/adni-data/6692397f-b246-4448-9112-3b790ac6ac28n%40googlegroups.com.

**CONFIDENTIALITY NOTICE** This e-mail communication and any attachments are for the sole use of the intended recipient and may contain information that is confidential and privileged under state and federal privacy laws. If you received this e-mail in error, be aware that any unauthorized use, disclosure, copying, or distribution is strictly prohibited. If you received this e-mail in error, please contact the sender immediately and destroy/delete all copies of this message.

[kostas ioannou]

Thank you very much for the immediate response! 

Best regards,

Konstantinos

To view this discussion on the web visit https://groups.google.com/d/msgid/adni-data/BYAPR08MB487236EF4A9B7281FA3B0653C05A9%40BYAPR08MB4872.namprd08.prod.outlook.com.