1. What is the Proportion of Days Covered (PDC)?

The Proportion of Days Covered (PDC) is a medication adherence measure that calculates the percentage of days a patient has medication available over a specific period. It is commonly used in healthcare to assess medication compliance.

2. How Does the Calculator Work?

The calculator uses the PDC formula:

Where:

• \( \text{covered days} \) — Number of days medication was available
• \( \text{total days} \) — Total number of days in the measurement period

Explanation: The formula calculates the proportion of days covered as a percentage, providing a measure of medication adherence over time.

3. Importance of PDC Calculation

Details: PDC is a crucial metric for healthcare providers to assess patient adherence to medication regimens, identify compliance issues, and improve treatment outcomes.

4. Using the Calculator

Tips: Enter the number of covered days and total days in the measurement period. Both values must be valid (covered days ≥ 0, total days > 0, and covered days ≤ total days).

5. Frequently Asked Questions (FAQ)

Q1: What is considered a good PDC score?
A: Typically, a PDC of 80% or higher is considered good adherence for most chronic medications.

Q2: How is PDC different from MPR?
A: While both measure medication adherence, PDC is generally considered more accurate as it accounts for overlapping medication supplies and provides a more conservative estimate.

Q3: What time period should be used for PDC calculation?
A: PDC is typically calculated over a specific measurement period, often 6 or 12 months for chronic medication adherence assessment.

Q4: Can PDC be greater than 100%?
A: No, PDC cannot exceed 100% as it represents a percentage of days covered within the total measurement period.

Q5: How is PDC used in healthcare quality measures?
A: PDC is used in various quality metrics and star ratings to evaluate medication adherence for conditions like diabetes, hypertension, and cholesterol management.