
DESCRIPTION OF ALL VARIABLE NAMES

Every row contains the data for a single trial.

main_id: A unique ID for a combination of records from the registries as assigned by ReAD-StuD
nct_id: Primary ID from clinicaltrials.gov
drks_id: Primary ID from DRKS
ictrp_id: The primary ID from ICTRP (the primary ID of the partner registry from which the trial was imported)
created_at: The registration dates from the different registries
des_q: Rating of the registration quality of the study design
des_a: Rating of the adherence of the published article to the registered study design
des_c: Comments on the study design
inc_q: Rating of the registration quality of the inclusion criteria
inc_a: Rating of the adherence of the published article to the registered inclusion criteria
inc_a_errtype: Whether the registration (r) or the published article (a) had more specific inclusion criteria (NA if identical)
inc_c: Comments on the inclusion criteria
int_q: Rating of the registration quality of the intervention
int_a: Rating of the adherence of the published article to the registered intervention
int_c: Comments on the intervention
pri_q: Rating of the registration quality of the primary outcome
pri_a: Rating of the adherence of the published article to the registered primary outcome
pri_c: Comments on the primary outcome
sec_q: Rating of the registration quality of the secondary outcome
sec_a: Rating of the adherence of the published article to the registered secondary outcome
sec_c: Comments on the secondary outcome
samp_register: The registered sample size from the different registries
samp_artikel: Reported sample size according to the published article
samp_q: Rating of the registration quality of the sample size
bli_q: Rating of the registration quality of the blinding
bli_a_old: Rating of the adherence of the published article to the registered blinding using the 'relaxed' rating criteria, meaning that double, triple, and quadruple blinding are regarded as equivalent
bli_a: Rating of the adherence of the published article to the registered blinding using more strict rating criteria, meaning that we do not automatically assume equivalence between double, triple and quadruple blinding unless the study details point to that
bli_register: The registered blinding
bli_article: The blinding from the accompanying publication
bli_errortype: If the blinding in the article was better, worse, or identical (ok) to the register. no_info if the information in the publication was insufficient.
bli_c: Comments on the blinding
tit_q: Quality rating of the title
tit_c: Comment on the title
link_desc: The type of the found publication ("ganzer Artikel" = full article; "kein Artikel" = no published article; "Poster" = poster; "Studienprotokoll" = study protocol; "Review" = review)
url: Link to the published material
article_earliest_date: The earliest known date at which the article was submitted or published
study_first_posted_date.aact: Date when a submission was made public on clinicaltrials.gov. The study_first_posted_date from the studies table of AACT
results_first_posted_date.aact: Date that a submission was made public on clinicaltrials.gov. The results_first_posted_date variable from the studies table of AACT
start_date.aact: study start date. The start_date variable from the studies table of AACT
completion_date.aact: study completion date. The completion_date variable from the studies table of AACT
study_type.aact: The study type, e.g. Interventional, from AACT
title.aact: The brief_title variable from the studies table of AACT
official_title.aact: The official_title variable from the studies table of AACT
overall_status.aact: The overall_status variable from the studies table of AACT, e.g. completed
phase.aact: The phase variable from the studies table of AACT
n.aact: The enrollment variable from AACT giving the number of patients
enrollment_type.aact: The enrollment_type variable from AACT, e.g. actual
source.aact: source variable from AACT. Similar to Lead sponsor, but may indicate who the data was submitted on behalf of, or a subsidiary of the sponsor.
prim_outcome.aact: The primary outcomes from the design_outcomes table of AACT, concatenated using ";"
sec_outcome.aact: The secondary outcomes from the design_outcomes table of AACT, concatenated using ";"
sec_id_ictrp: Secondary IDs from ICTRP
title.ictrp: The public_title variable from ICTRP
official_title.ictrp: The Scientific_title variable from ICTRP
email_scientific.ictrp: The Scientific_Contact_Email variable from ICTRP
email_public.ictrp: The Public_Contact_Email variable from ICTRP
study_type.ictrp: The study_type variable from ICTRP, e.g. Observational
study_design.ictrp: The study_design variable from ICTRP giving details on allocation, masking etc.
phase.ictrp: The study phase variable from ICTRP, e.g. IV
created_at.ictrp: The registration date from ICTRP
start_date.ictrp: The Date_enrollment variable from ICTRP
n.ictrp: The Target_size variable from ICTRP
overall_status.ictrp: The Recruitment_status variable from ICTRP, e.g. Recruiting
name.ictrp: The Primary_sponsor variable from ICTRP. Name of the primary sponsor
secondary_sponsors.ictrp: The Secondary_sponsors variable from ICTRP. Names are concatenated using ";"
countries.ictrp: The recruiting countries from ICTRP, all lower case and concatenated using ";"
interventions.ictrp: The Interventions variable from ICTRP, giving descriptions of the interventions. Concatenated using ";"
inclusion_criteria.ictrp: The Inclusion_criteria variable from ICTRP, giving descriptions of the inclusion criteria as free text. Note that some trials combined exclusion and inclusion criteria in this field.
exclusion_criteria.ictrp: The Exclusion_criteria variable from ICTRP, giving descriptions of the exclusion criteria as free text
prim_outcome.ictrp: The primary outcome descriptions from ICTRP, concatenated using ";"
sec_outcome.ictrp: The rimary outcome descriptions from ICTRP, concatenated using ";"
sec_id_drks: Secondary IDs from DRKS, concatenated using ";"
created_at.drks: Variable firstDrksPublishDate from DRKS
investorInitiated.drks: Variable investorInitiated from DRKS
indication.drks: Variable indication from DRKS, concatenated using ";"
intervention.drks: Variable intervention from DRKS, giving descriptions of the individual arms, concatenated using ";"
study_type.drks: Variable type from DRKS, e.g. Interventional
allocation.drks: Variable allocation from DRKS, e.g. Randomized controlled trial
masking.drks: Variable masking from DRKS, e.g. Blinded
control.drks: Variable control from DRKS, e.g. Placebo
assignment.drks: Variable assignment from DRKS, e.g. Parallel
phase.drks: Variable phase from DRKS, e.g. II
prim_outcome.drks: Variable primaryEndpoint from DRKS, giving the description of the primary outcome variable
sec_outcome.drks: Variable secondaryEndpoints from DRKS, giving descriptions of the secondary outcome variables, concatenated using ";"
countries.drks: Countries of recruitment from the countries variable of DRKS, concatenated using ";"
recruit_locations.drks: Recruitment locations, e.g. University Medical Center Bochum, from the recruit_location variable of DRKS, concatenated using ";"
start_date.drks: Study start date from the variable startDate of DRKS
plannedActual.drks: Variable plannedActual from DRKS, whether start_date.drks is planned or the actual start date
n.drks: targetSize variable from DRKS, giving the target sample size
studyEnd.drks: studyEnd variable from DRKS
inclusion.drks: inclusion variable from DRKS, giving the inclusion criteria as free text
exclusion.drks: exclusion variable from DRKS, giving the exclusion criteria as free text
official_title.drks: Variable title from DRKS, usually corresponds to official_title from AACT
recruitmentStatus.drks: Variable recruitmentStatus from DRKS, e.g. Recruiting ongoing
name.drks: Variable affiliation from DRKS, concatenated using ";"
email_central.drks: Variable email from DRKS, concatenated using ";"
publications.drks: Variable publications from DRKS, concatenated using ";"
summarized_start_date: A start date variable that summarizes all start_date fields by first looking for a start date in start_date.aact, then in start_date.drks, then in start_date.ictrp and returning the one that was found first
study_first_submitted_date.aact: The _submitted suffix indicates the date that the responsible party pressed the release button in the ClinicalTrials.gov data submission system, thereby submitting the data for review prior to posting.
summarized_first_posted: A variable that summarizes study_first_submitted_date.aact, created_at.drks, and created_at.ictrp by taking the earliest date from these variables
summarized_n: A sample size variable that summarizes all sample size fields from AACT, DRKS, and ICTRP by ordering study_first_submitted_date.aact, created_at.drks, and created_at.ictrp and returning the sample size from the register where the study was registered first
summarized_study_type: A study type variable that summarizes all study type fields from AACT, DRKS, and ICTRP by ordering study_first_submitted_date.aact, created_at.drks, and created_at.ictrp and returning the study type from the register where the study was registered first
is_exz: Binary variable for whether involvement of a University of Excellence was detected
is_koor: Binary variable for whether involvement of a Coordinating Center for Clinical Trials was detected
pre_nct: Binary variable for whether the study was pre-registered according to the dates in AACT
pre_drks: Binary variable for whether the study was pre-registered according to the dates in DRKS
pre_ictrp: Binary variable for whether the study was pre-registered according to the dates in ICTRP
summarized_pre: Combination of the previous three variables as TRUE / FALSE
has_univ_aact: Binary variable for whether any type of university was involved in the study according to AACT
has_univ_ictrp: Binary variable for whether any type of university was involved in the study according to ICTRP
has_univ_drks: Binary variable for whether any type of university was involved in the study according to DRKS
has_univ: TRUE if any of the previous three variables is TRUE
start_year: The year from summarized_start_date
has_nct: Binary variable for whether the study was registered on ClinicalTrials.gov
has_drks: Binary variable for whether the study was registered on the DRKS
has_euctr: Binary variable for whether the study was registered on clinicaltrialsregister.eu

