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Hello,
the LME model accounts for dependencies between timepoints, but does so in a flexible way: it does not require the same number of observations for each participant, nor does it require identical intervals between observations. Also including a single timepoints for some cases is fine.
In general, one can think of it as a regression problem: sometimes more data/timepoints are available to model the slopes across time, sometimes less. This probably affects the precision of the estimates, but apart from that, varying numbers of timepoints and variable intervals are not a fundamental problem for LME models.
Best regards,
Kersten
Am 10.07.2023 um 22:11 schrieb Lara Foland-Ross <lfoland@stanford.edumailto:lfoland@stanford.edu>:
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Hi there,
We have a longitudinal structural neuroimaging dataset with anywhere between 1 and 4 timepoints collected for each participant. How does LME handle missing data when analyzing longitudinal trends?
Thanks, Lara
Lara Foland-Ross, Ph.D. Senior Research Associate and Imaging Lab Manager Center for Interdisciplinary Brain Sciences Research Stanford University School of Medicine 401 Quarry Road, Room 1356 Stanford, CA 94305-5795 _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edumailto:Freesurfer@nmr.mgh.harvard.edu https://secure-web.cisco.com/1YFT6sc5KEjTJ6SNF0Zj5pYIJjLHLEjKyN57OOschlwEAG-... The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Mass General Brigham Compliance HelpLine at https://secure-web.cisco.com/18As-1tcAkt__g7AZ6AIuQSJbyECIdUxWskHXBLN5HautSt... https://secure-web.cisco.com/18As-1tcAkt__g7AZ6AIuQSJbyECIdUxWskHXBLN5HautStMmfOUMs_fYThi-fFHETa1ayQuqSYNMxrxkbVGgEzJYNuhZjveUTXGXBfsUszePv25b5vkskZJRV8RbnmtKTolBmQ5NkLq-nkbYGR2vwv7r1kqyxbTIOdWY0UC90ygC4WKmlIUpEmVZRJ-xHotto0ilyQbRQsoKwmMcAPtkDKktdnY_slMqTaWfRGNE4z50cyKHpGAcko_AXpeSwENWFNGdimVCepMxMngmSmwYg2X2w8dtxKbg1O6clmmfid7ntQt1i4zPV7m511pfDyPpYuku2Bf-_DIburmjbcy9tg/https%3A%2F%2Fwww.massgeneralbrigham.org%2Fcomplianceline . Please note that this e-mail is not secure (encrypted). If you do not wish to continue communication over unencrypted e-mail, please notify the sender of this message immediately. Continuing to send or respond to e-mail after receiving this message means you understand and accept this risk and wish to continue to communicate over unencrypted e-mail.
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