Introduction

This concept describes how to identify a list of drug identification numbers (DINs) relating to a specific drug or class of drugs. Using Health Canada's Drug Product Database (DPD) as the main source of information on DINs, plus supplemental information from Manitoba Health's Drug Product Information Network (DPIN) (specifically the DIN Master File) comprehensive DIN lists are created so that further analysis (i.e. cohort identification, variable creation, drug utilization measures) may be done on a specific drug or class of drugs.

Methods

Health Canada's Drug Product Database (DPD) is used as the main source of drug information for products approved for use in Canada. At MCHP, a SAS file of the DPD called the Updated DIN Master (UDM) file has been created and is updated annually. Additional products are identified from the Manitoba Health Drug Product Information Network's (DPIN) DIN Master file (limited to DINs which appear on the DIN Master File, but do not appear on the DPD).

DIN selection requires the user to have at least one of the following:


• Anatomical Therapeutic Classification (ATC) Code from the Anatomical Therapeutic Classification (ATC) Drug Classification System
  
• Generic Name of the Drug(s)
  
• Brand Name of the Drug(s)
  
• Actual DIN(s)

All records from the most recent UDM are queried based on the ATC code(s) and/or generic name(s) and/or brand name(s). Some DINs may be selected that either had a different ATC code in the past, or based on the generic name may have a different ATC code than what was initially queried on. Thus, additional DINs are identified based on all of the ATC codes that could have occurred for the initial DIN selection over time. A review of these DINs is required to confirm inclusion/exclusion. Additionally, a similar process is applied for the generic names and the ingredient names. If a generic name (or ingredient) has been identified (by ATC code selection) that was not provided in the initial selection (or no generic names and/or ingredient names were provided at all), then selection of additional DINs are made based on similar generic names and ingredient names. Review of the selected DINs is required again. Once all the DINs from the UDM have been confirmed as ones to be included in the DIN list then the most recent record on the UDM for each DIN is kept.

The most recent record for each DIN from the DIN Master File (which was not found on the UDM File) is then queried using the same ATC code selection, and same similar generic name selection. Review of these additional DINs is required. Once these DINs have been confirmed for inclusion they are combined with the DINs selected from the UDM. This completes the DIN list. Final review by the researcher or a pharmacist may be necessary.

Limitations/Cautions

The following limitations/cautions are provided for working with the DIN data:


• Specific projects may have certain exclusion/inclusion criteria for their DIN list. If your project wants to use a DIN list from a different project for the same drug category, then confirm the exclusions/inclusions are relevant to that project.
  
• Any DIN list code should be reviewed again if a new year of the UDM has been added to avoid missing any new products.
  
• When using the ingredients variable for identifying additional DINs for possible inclusion it is important to know that this variable lists all ingredients for a product in alphabetical order. Thus, products with more than one medicinal ingredient may not have ingredient of your selection listed first and products not relevant to your project will be identified. Review of DINs throughout the selection process is required to catch these.
  
• Depending on the project, the project's timeframe, how the prescription drug information is to be used, and the drug or drug class being looked at a simplified version of creating a DIN list can be used by selecting on ATC code alone. Approximately 99.7% of all prescriptions in the data are for products for which there is an ATC code available on the Updated DIN Master File.

Examples of Medication Lists using ATC Code and Drug Identification Numbers (DINs)

The following lists provide examples of medications that have been used in the identification of certain diseases/conditions in the How Are Manitoba's Children Doing? (2012) deliverable. These lists include the ATC codes and/or the DINs that have been used in the identification.


• Asthma Medication List
  
• Attention-Deficit Hyperactivity Disorder (ADHD) Medication List
  
• Diabetes Medication List
  
• Mood and Anxiety Disorders Medication List

SAS Code

An example SAS program that provides a template for creating DIN lists is available in the SAS code and formats section below (internal access only).