R/data.R

In rsmatch: Matching Methods for Time-Varying Observational Studies

#' Longitudinal MRI data in nondemented and demented older adults.
#'
#' A dataset containing baseline and time-varying information relating to
#' Alzheimer's disease (AD) based on the [Open Access Series of Imaging
#' Studies](https://www.oasis-brains.org/) (OASIS). This set consists of a
#' longitudinal collection of 51 subjects aged 62 to 92. Each subject was
#' scanned on two or more visits, separated by at least one year for a total of
#' 115 imaging sessions. For each subject, 3 or 4 individual T1-weighted MRI
#' scans obtained in single scan sessions are included.
#'
#' The data was originally hosted in this Kaggle repository:
#' [https://www.kaggle.com/jboysen/mri-and-alzheimers?select=oasis_longitudinal.csv](https://www.kaggle.com/jboysen/mri-and-alzheimers?select=oasis_longitudinal.csv).
#' It has been harmonized for an example analysis for risk set matching based on
#' a reduced sample including patients who go from mild cognitive impairment
#' (MCI) to AD and those patients with MCI throughout.
#'
#' @format A data frame with 115 rows and 11 variables:
#' \describe{
#'   \item{subject_id}{unique subject identifier}
#'   \item{visit}{visit order}
#'   \item{time_of_ad}{visit in which a patient first had AD diagnosis}
#'   \item{m_f}{male or female}
#'   \item{educ}{years of education}
#'   \item{ses}{socioeconomic status (-1 for missing)}
#'   \item{age}{age of patient at visit}
#'   \item{mr_delay}{MR delay time (contrast)}
#'   \item{e_tiv}{estimated total intracranial volume}
#'   \item{n_wbv}{normalized whole brain volume}
#'   \item{asf}{atlas scaling factor}
#' }
#' @source
#'   \url{https://www.kaggle.com/jboysen/mri-and-alzheimers?select=oasis_longitudinal.csv}
#'
"oasis"