Related Experiment Video
Updated: Jun 25, 2026
09:42
Using Continuous Data Tracking Technology to Study Exercise Adherence in Pulmonary Rehabilitation
Published on: November 8, 2013
Comparison of methods to assess medication adherence and classify nonadherence
Richard A Hansen1, Mimi M Kim, Liping Song
1Division of Pharmaceutical Outcomes and Policy, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Campus Box 7360, 2205 Kerr Hall, Chapel Hill, NC 27599, USA. rahansen@unc.edu
The Annals of Pharmacotherapy
|March 6, 2009
Summary
Patient self-report, pharmacy refill, and electronic monitoring show similar medication adherence estimates. Refill and electronic measures had the highest agreement, with an 80% threshold balancing sensitivity and specificity.
Area of Science:
- Pharmacoeconomics and Health Outcomes Research
- Clinical Pharmacy and Practice
- Patient Adherence Studies
Background:
- Suboptimal medication adherence presents challenges for clinicians and researchers in identifying nonadherent patients.
- Existing adherence measures lack consensus regarding data acceptability and definitions of nonadherence.
Purpose of the Study:
- To evaluate agreement between patient self-report, pharmacy refill, and electronic adherence measures.
- To compare the sensitivity and specificity of various cut-points for defining medication nonadherence.
Main Methods:
- Analysis of data from two randomized controlled trials on pharmacist interventions for medication adherence in hypertension or heart failure.
- Adherence measurement via patient self-report, prescription refill records, and electronic monitoring devices.
- Assessment of inter-measure agreement using Spearman's correlation coefficient (rho) and Fisher's Z transformation; calculation of sensitivity and specificity for different adherence cut-points.
Main Results:
- Median adherence rates were 84% (self-report), 86% (electronic), and 91% (refill).
- Pharmacy refill and electronic measures exhibited the strongest agreement (rho = 0.48).
- Patient characteristics like age, depression, and comorbidities influenced measure agreement. An 80% adherence cut-point demonstrated a balanced sensitivity and specificity across measures.
Conclusions:
- All adherence measures yielded comparable overall adherence estimates, with refill and electronic methods showing the highest concordance.
- Selection of an adherence measure should account for population and disease-specific factors influencing measurement agreement.
- A commonly used 80% adherence threshold offers a reasonable balance of sensitivity and specificity for studies involving patients with heart failure or hypertension.
Related Concept Videos
01:20Measurement of Bioavailability: Pharmacodynamic Methods
Pharmacodynamic methods provide insights into a drug's effects on physiological processes over time and play a crucial role in understanding bioavailability and therapeutic efficacy. These methods can be broadly classified into acute pharmacological and therapeutic response approaches, each with distinct mechanisms and applications.The acute pharmacological response method directly correlates a drug's physiological effects, such as ECG or pupil diameter changes, to its time course in the body.
01:28Drug Therapy
The advent of drug therapy has profoundly shaped modern mental health care, providing targeted treatments for a range of psychological disorders. Psychotherapeutic drugs, classified into antianxiety, antidepressant, and antipsychotic medications, address symptoms across anxiety disorders, mood disorders, and schizophrenia. While these medications have transformed patient outcomes, they require careful management due to their potential side effects and limitations.
Antianxiety Medications
Antianxiety Medications
00:59Model-Independent Approaches for Pharmacokinetic Data: Noncompartmental Analysis
Noncompartmental analyses offer an alternative method for describing drug pharmacokinetics without relying on a specific compartmental model. In this approach, the drug's pharmacokinetics are assumed to be linear, with the terminal phase log-linear. This assumption allows for simplified analysis and interpretation of the drug's behavior in the body.
One important characteristic of noncompartmental analyses is that drug exposure increases proportionally with increasing doses. This relationship...
One important characteristic of noncompartmental analyses is that drug exposure increases proportionally with increasing doses. This relationship...
01:25Drug Classes and Categories
Drugs can be classified according to their chemical composition or their intended therapeutic application. For instance, anti-infective agents that possess the ability to eliminate pathogens or suppress their growth and reproduction can be grouped based on the organisms they target or their chemical structure. Furthermore, drugs can be divided into prescription, nonprescription, or controlled substances. Prescription medications, such as antibiotics, require oversight from a licensed healthcare...
02:07Blind Procedures
Ideally, the people who observe and record the children’s behavior are unaware of who was assigned to the experimental or control group, in order to control for experimenter bias. Experimenter bias refers to the possibility that a researcher’s expectations might skew the results of the study. Remember, conducting an experiment requires a lot of planning, and the people involved in the research project have a vested interest in supporting their hypotheses. If the observers knew which child was...
01:26Therapeutic Drug Monitoring: Drug Analysis Methods
Therapeutic Drug Monitoring (TDM) is a clinical practice that measures specific drug levels in a patient's blood or body tissues to tailor drug therapy effectively. This monitoring is critical for managing drugs with narrow therapeutic indices like digoxin and phenytoin, ensuring they are both safe and effective. For instance, monitoring theophylline levels in asthma patients involves precision and sensitivity to adjust doses according to individual responses to therapy, ensuring efficacy and...