Association Between Cost and
Quality of Care Provided by
Individual Physicians
Peter Hussey, Ateev Mehrotra, John Adams,
Julie Lai, Bill Thomas, Elizabeth McGlynn
Study Sample
 2004
2004--5 claims
l i
from
f
4 Massachusetts
M
h
tt health
h lth plans
l
 Combined database:
• ~90% patients with commercial health insurance
• 2.9 million enrollees
 Analyses focus on continuously enrolled adults between 18–
18–65
years old
 6,139 MDs in 7 specialties
 Eligible for at least 10 unique quality indicators
 Excluded pediatric specialties and specialties with no direct
patient care
 Excluded residents
Hussey - 2 - 6/10
We Used an EpisodeEpisode-Based Cost
M
Measurement
A
Approach
h
 Each patient’s claims divided into
episodes of care
 Episode
E i d off care is
i all
ll care provided
id d over
a period of time for a specific condition
•
e.g. Pneumonia – first through last claim
for pneumonia
pneumonia--related care
 Episodes defined using Symmetry ETG
grouper
Hussey - 3 - 6/10
We Calculated a Cost Score for Each
Ph i i
Physician

Each episode assigned to physician with
greatest fraction of costs

Calculated for each episode Actual Costs &
Expected Costs

Expected Costs = average costs among
episodes assigned to physicians of same
specialty
p
y adjusted
j
for patient
p
co-morbidities
coSum of Actual Costs
Composite Cost Profile =
--------------------------------Sum of Expected Costs
Hussey - 4 - 6/10
Quality Measured Using ClaimsClaims-Based RAND
QA T
Tools
l
 Used
U d only
l underuse
d
measures
 Subset of measures developed using RANDRAND-UCLA modified
Delphi method and used in RAND national study of quality
 117 unique
q quality
q
y indicators covering
g 20 acute and chronic
conditions plus preventive care
 Performance scores were created by dividing all instances in
which recommended care was delivered by the number of times
patients were eligible for such care
 Adjusted for “degree of difficulty” by subtracting mean from
each performance score
Hussey - 5 - 6/10
Analyses
 Correlation
C
l ti between
b t
physician
h i i costt and
d quality
lit scores
 Separate analysis by physician specialty type:
 Primary care (internal medicine, family medicine)
 Specialists (cardiology, endocrinology, nephrology,
pulmonary
p lmonar & critical care)
 Obstetrics/gynecology
 Separate analysis by type of care: acute, chronic, preventive
 Performed bivariate empirical Bayes shrinkage to adjust raw
outcomes in proportion to the amount of information in each
estimate
Hussey - 6 - 6/10
No Significant CostCost-Quality Association in
A
Aggregate
t A
Analysis
l i
Hussey - 7 - 6/10
Small, Positive Correlation in Analysis by
T
Type
off Care
C
All specialties
Hussey - 8 - 6/10
Correlation Stronger for Specialists
Primary Care
Specialists
Ob/Gyn
Hussey - 9 - 6/10
Conclusions
 Cost
C
Costt-quality
lit correlation
l ti is
i positive
iti or nonnon-significant
i ifi
t
 Aggregate analyses may mask differences by type of
care and specialty
 Cost
Cost--quality relationship at the physician level may
differ from area level
 Underscores the importance of accounting for
quality in value
value--based purchasing
purchasing, bundled payment,
payment
tiered networks, and other policy interventions that
create incentives to decrease costs
Hussey - 10 - 6/10