Castor API R Package

The intent of this package is to provide convenient access to study data in Castor via R.

Package Structure

Access to data in the API comes in three forms:

1. Access to individual items (getStudyDataPoint, getStudy, getRecord, etc.)
2. Access to pages of items in a list (getStudyDataPoints, getStudies, getRecords, etc.)
3. Processed into a data frame for straightforward analysis (getStudyData)

Installation

# install.packages("remotes")
remotes::install_github("castoredc/castoRedc")

Missing data

In the package, user missing data is handled in the following way. For date variables, they are represented by 31-12-29XX, where XX (95-99) indicates the type of missing data. For numeric variables, they are represented by the values -99 to -95, where 95 to 99 represent the type of missing data in Castor. For non-numeric variables, they are represented by ##_USER_MISSING_XX## where XX (95-99) indicates the type of missing data.

Testing

If you want to test the package, for example when developing, please fill in create_testing_credentials.R.
You should supply an example for each of the study, report, etc. Please make sure that the record has a value in the field. And that the report step is a child of the report.

Usage

See https://helpdesk.castoredc.com/article/124-application-programming-interface-api about generating your credentials.

Note: It is recommended that you read https://cran.r-project.org/web/packages/httr/vignettes/secrets.html about managing your credentials.

library(castoRedc)

castor_api <- CastorData$new(key = credentials$client_id, 
                             secret = credentials$client_secret, 
                             base_url = "https://data.castoredc.com")

studies <- castor_api$getStudies()

(example_study_id <- studies[["study_id"]][1])
#> [1] "15E88A04-9CB8-4B30-9A3C-B1DBFC96CD88"

study <- castor_api$getStudyData(example_study_id)

fields <- castor_api$getFields(example_study_id)

forms <- castor_api$getForms(example_study_id)

visits <- castor_api$getVisits(example_study_id)