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Check whether ClinicalTrials.gov registrations were prospective

Source: R/rt_registration.R
rt_registration_timing.Rd

Looks up trials in the ClinicalTrials.gov registry (API version 2) and compares the date the registration was first submitted with the study start date. A registration is prospective when it was submitted no later than the start date (plus an optional grace period).

Usage

rt_registration_timing(nct_ids, grace_days = 0)

Arguments

nct_ids

A character vector of NCT numbers, for example from [rt_trial_ids()]. Other identifiers are returned with `NA` dates.

grace_days

Days after the start date within which a registration still counts as prospective (default `0`). Some studies allow 30 days.

Value

A tibble with one row per unique identifier: `nct_id`, `first_submitted` and `first_posted` (the registration dates), `start_date`, `start_date_precision` (`"day"` or `"month"`), `start_date_type` (`"ACTUAL"` or `"ESTIMATED"`), `days_after_start` (submission date minus start date; negative when registered before the start) and `is_prospective`. Trials the registry does not know have `NA` dates.

Details

When the registry gives the start date to the month only, a registration submitted within that month cannot be classified and `is_prospective` is `NA`; one submitted before the month is prospective and one after it is retrospective. The start date the registry holds may be an estimate for trials not yet started (`start_date_type`).

See also

[rt_trial_ids()], [rt_register_pmc()]

Examples

# \donttest{
# Needs internet access and the jsonlite package.
if (requireNamespace("jsonlite", quietly = TRUE)) {
  try(rt_registration_timing(c("NCT04368728", "NCT00000102")))
}
#> # A tibble: 2 × 8
#>   nct_id      first_submitted first_posted start_date start_date_precision
#>   <chr>       <date>          <date>       <date>     <chr>               
#> 1 NCT04368728 2020-04-27      2020-04-30   2020-04-29 day                 
#> 2 NCT00000102 1999-11-03      1999-11-04   NA         NA                  
#> # ℹ 3 more variables: start_date_type <chr>, days_after_start <int>,
#> #   is_prospective <lgl>
# }