Table 1A

List of variables to be included in the analysis

VITAL-DEP*Claims†Variable assessment period
Vital study
Randomisation groupVITAL data measurement point closest to index depression diagnosis date
 Vitamin D3 X
 Placebo X
Pill compliance X VITAL data measurement point closest to index depression diagnosis date
 Past month—days missed X
Side effects X VITAL data measurement point closest to index depression diagnosis date
 Stomach upset or pain X
 Nausea X
 Constipation X
 Diarrhoea X
 Skin rash X
 Colds or URI X
 Influenza-like symptoms X
 Frequent nosebleeds X
 Easy bruising X
 Blood in urine X
 GI bleeding X
 Bad taste in mouth X
Patient-level characteristics
DemographicsVITAL data measurement point closest to index depression diagnosis date
 Race/ethnicity X
 Age X
 Sex X
 Level of education X
 Marital status X
 Employment status X
 Household income X VITAL data measurement point closest to index depression diagnosis date
 Geographic region/state X VITAL data measurement point closest to index depression diagnosis date
Lifestyle and psychosocial factorsVITAL data measurement point closest to index depression diagnosis date
 Smoking status X
 Alcohol use X
 Diet (Healthy Eating Index) X
 Physical activity X
 Lost 5 lbs. or more in past 2 years X
 Body mass index X
 Limitation in daily activity X
 Independence in living X
Dietary supplement intakeVITAL data measurement point closest to index depression diagnosis date
 Vitamin D X
 Fish oil (incl. krill, cod liver at YR 2) X
 Other supplmt. Containing Omega-3 X
 Calcium X
 Multivitamins X
 Vitamin A X
 Any other supplements X
Depression diagnosis-related factorsVITAL data measurement point closest to index depression diagnosis date
Mood and depression scores (PHQ-8) X
Self-reported depression diagnosis X
Self-reported core depressive symptoms, 2 weeks X
Self-reported depression treatment, medications and/or counselling X
Depression diagnoses, in CMSRefer to online supplementary file for codesFrom V3 date to end* of claims data
Date of depression diagnosis, in CMSRefer to online supplementary file for codes
Other mental health disordersRefer to online supplementary file for codes180 days prior to index depression diagnosis date (inclusive)
 DementiaRefer to online supplementary file for codes
 Delirium/psychotic disorderRefer to online supplementary file for codes
 Mood and anxietyRefer to online supplementary file for codes
 SchizophreniaRefer to online supplementary file for codes
 Manic disorderRefer to online supplementary file for codes
 Bipolar disorderRefer to online supplementary file for codes
 Attention deficit disorderRefer to online supplementary file for codes
 Intellectual disabilitiesRefer to online supplementary file for codes
Chronic comorbiditiesRefer to online supplementary file for codes180 days prior to index depression diagnosis date (inclusive)
 Coronary artery diseases X Refer to online supplementary file for codes
 Myocardial infarction X Refer to online supplementary file for codes
 Valvular heart disease X Refer to online supplementary file for codes
 Heart failure X Refer to online supplementary file for codes
 Stroke X Refer to online supplementary file for codes
 Peripheral artery disease X Refer to online supplementary file for codes
 Chronic obstructive pulmonary disease X Refer to online supplementary file for codes
 Asthma X Refer to online supplementary file for codes
 Hypertension X Refer to online supplementary file for codes
 Diabetes mellitus X Refer to online supplementary file for codes
 End-stage renal disease X Refer to online supplementary file for codes
 Macular degeneration X Refer to online supplementary file for codes
 Parkinson disease X Refer to online supplementary file for codes
 Dementia X Refer to online supplementary file for codes
 Cancer X Refer to online supplementary file for codes
 AIDS X Refer to online supplementary file for codes
 Traumatic brain injuryRefer to online supplementary file for codes
 Combined comorbidity score (mean)
Prior medication use (please provide flags (1/0) for each class of medication listed below and the unique drug names (character variable) as a separate variable)180 days prior to index depression diagnosis date (inclusive)
Psychiatric medicationsRefer to online supplementary appendix B for codes
 AntidepressantsRefer to online supplementary appendix B for codes
 1. First-generation agentsRefer to online supplementary appendix B for codes
 2. Second-generation agentsRefer to online supplementary appendix B for codes
 3. Third-generation agentsRefer to online supplementary appendix B for codes
 StimulantsRefer to online supplementary appendix B for codes
 AntipsychoticsRefer to online supplementary appendix B for codes
 Mood stabilisersRefer to online supplementary appendix B for codes
 Antianxiety agentsRefer to online supplementary appendix B for codes
 First-generation (typical) antipsychoticsRefer to online supplementary appendix B for codes
 Second-generation (atypical) antipsychoticsRefer to online supplementary appendix B for codes
 Other psychotropicRefer to online supplementary appendix B for codes
Number of unique psychiatric medications (mean)Total counts of unique psychiatric medications filled
Index prescription filled
AntidepressantsRefer to online supplementary appendix B for codesDuring follow-up‡
 1. First-generation agentsRefer to online supplementary appendix B for codes
 2. Second-generation agentsRefer to online supplementary appendix B for codes
 3. Third-generation agentsRefer to online supplementary appendix B for codes
StimulantsRefer to online supplementary appendix B for codes
AntipsychoticsRefer to online supplementary appendix B for codes
Mood stabilisersRefer to online supplementary appendix B for codes
Antianxiety agentsRefer to online supplementary appendix B for codes
First-generation (typical) antipsychoticsRefer to online supplementary appendix B for codes
Second-generation (atypical) antipsychoticsRefer to online supplementary appendix B for codes
Other psychotropicRefer to online supplementary appendix B for codes
Characteristics of index prescription filledOn index prescription filled date
Prescription type—brand vs genericFrom Medicare Part D files
Days’ supplyFrom Medicare Part D files
Quantity dispensedFrom Medicare Part D files
Patient out-of-pocket spending on index fillFrom Medicare Part D files
Dispensed as writtenFrom Medicare Part D files
Low-income subsidy for index drugFrom Medicare Part D files
Drug coverage statusFrom Medicare Part D files
Healthcare utilisation and healthcare system-relatedFrom MedPAR, Inpatient, Outpatient, Carrier files180 days prior to index depression diagnosis date (inclusive)
Visit with psychiatrist in the pastFrom MedPAR, Inpatient, Outpatient, Carrier files
Use of psychotherapy servicesFrom MedPAR, Inpatient, Outpatient, Carrier files
Number of physician office visits (unique counts)From MedPAR, Inpatient, Outpatient, Carrier files
Number of hospitalisations (mean)From MedPAR, Inpatient, Outpatient, Carrier files
 Psychiatric relatedFrom MedPAR, Inpatient, Outpatient, Carrier files
Number of unique prescribersCounts of number of unique prescribers who wrote any prescription for participants in the study cohort. Each prescriber with a unique ID is counted once from Medicare Part D files
Number of unique providersCounts of number of unique providers who wrote any prescription for participants in the study cohort. Each provider with a unique ID is counted once from MedPAR, Inpatient, Outpatient, Carrier files
Visit with both psychiatrist and PCP in prior 180 daysFlag for patients who had at least one visit with both a psychiatrist and PCP in prior 180 days. This information will be assessed from MedPAR, Inpatient, Outpatient, Carrier files
Copay/coinsurance associated with office visit during depression diagnosisThe sum of the copay and coinsurance associated with the depression diagnosis. This information will be assessed from MedPAR, Inpatient, Outpatient, Carrier files
Number of unique pharmaciesCounts of different unique pharmacies where patient filled any medication. Each pharmacy with a unique ID is counted once. This information will be assessed from Medicare Part D files
Provider characteristicsIndex depression diagnosis date
Provider type and place of serviceFrom MedPAR, Inpatient, Outpatient, Carrier files
 Psychiatrist-OfficeFrom MedPAR, Inpatient, Outpatient, Carrier files
 Psychiatrist-OtherFrom MedPAR, Inpatient, Outpatient, Carrier files
 Nurse practitionerFrom MedPAR, Inpatient, Outpatient, Carrier files
 HospitalFrom MedPAR, Inpatient, Outpatient, Carrier files
 PCP-OfficeFrom MedPAR, Inpatient, Outpatient, Carrier files
 PCP-OtherFrom MedPAR, Inpatient, Outpatient, Carrier files
Geographic location of providerFrom MedPAR, Inpatient, Outpatient, Carrier filesIndex depression diagnosis date
 NortheastFrom MedPAR, Inpatient, Outpatient, Carrier files
 SouthFrom MedPAR, Inpatient, Outpatient, Carrier files
 MidwestFrom MedPAR, Inpatient, Outpatient, Carrier files
 WestFrom MedPAR, Inpatient, Outpatient, Carrier files
  • *VITAL-DEP variables will be assessed at the closest study visit prior to date of index depression diagnosis.

  • †Claims-based covariates will be assessed during the 6-month period prior to date of index depression diagnosis.

  • ‡Follow-up duration (in days)=index date–first of (date of death, disenrolment, or end of available data).

  • CMS, Centers for Medicare and Medicaid Services; PCP, primary care physician; PHQ, Patient Health Questionnaire; VITAL-DEP, Vitamin D and Omega-3 Trial-Depression Endpoint Prevention.