Comparative Effectiveness Research and Sources of Data for Pharmacoepidemiological Studies

Question 1

Comparative Effectiveness Research

Answer 1

A rigorous evaluation of the impact of different options that are available for treating a given medical condition for a particular set of patients. Such a study may compare similar treatment, such as competing drugs, or it may analyze very different approaches, such as surgery and drug therapy.

Question 2

Drug Efficacy

Answer 2

Investigated whether a drug has the ability to bring about the intended effect

Question 3

Drug Effectiveness

Answer 3

Investigates whether in the real world a drug in fact achieves its desired effect

Question 4

What data can we use for non-experimental studies

Answer 4

Large cohort studies
Healthcare and clinical databases
Disease registries
Drug registries
Publicly available survey data
HMO/health plans
Commercial insurance databases
US Government Claims database
Medical record database
In-hospital databases

Question 5

Desired qualities of a database

Answer 5

Representative
Large
Timely
Continuity
Linkage on unique identifier
Accessible

Question 6

Strengths of HMO databases

Answer 6

Large, diverse, defined populations
Automated claims, EMR data, access to providers
Varied delivery models and practice patterns
Large cohorts can be identified to measure incidence of rare events or with specific exposures
Research centers’ ability to contact health plan enrollee for participation in clinical research

Question 7

Weakness of HMO databases

Answer 7

Absence of population groups that are uninsured
Smaller fraction of the elderly than the general populations
Prescription medication filled out-of-plan, nonprescription medications, and inpatient drug dispensing not routinely captured

Question 8

Medicaid

Answer 8

Low income pregnant women and members of low income families with children
Chronically disabled
Low-income seniors

Question 9

Medicare

Answer 9

Nearly all US resident age 65 and above
Permanently disabled adults younger than 65
Part D (outpatient Rx drug coverage)

Question 10

Strengths of government insurance

Answer 10

Population size and length of follow-up
Accuracy of pharmacy claims
Validity of procedure claims
Over-representation of underserved populations
Ability to validate outcomes
Ability to link to external data

Question 11

Weaknesses of government insurance

Answer 11

Non-representativeness
Unavailable information
Limitations in prescription coverage
Eligibility
Data validity/access to medical records
Out of plan care

Question 12

In-hospital databases

Answer 12

Non-experimental studies are important approach to assess comparative effectiveness and safety of medication in hospitalized patients

Question 13

PHIS database

Answer 13

Comparative pediatric database containing clinical and financial data elements

Question 14

Premier database

Answer 14

Consortium of US not-for-profit hospitals and health systems
Contains information on more than 130 million patient discharges
Fewer than 1% of patient records are missing with some key elements with less than 0.1% of missing data

Question 15

Strengths of in-hospital database

Answer 15

Sample size
Versatile data source
Data quality
Efficient
Data longevity

Question 16

Weaknesses of in-hospital database

Answer 16

Generalizability of study findings can be questioned
Possibly misclassification of data
Ascertainment bias: hospitalized patients have different lengths of stay, vary across hospitals