Table 1.

Variable Description

Dependent variables
BCS	Percentage of continuously enrolled women between age 52 and 69 who had a mammogram during the measurement year
AMMR	Percentage of continuously enrolled adolescents who turned 13 years old during the measurement year and had a second dose of MMR immunization by 13th birthday
AHB	Percentage of continuously enrolled adolescents who turned 13 years old during the measurement year and had three hepatitis B immunizations or complete two-dose regimen by 13th birthday
A1c Test	Percentage of continuously enrolled members with diabetes (Type 1 and Type 2) age 18–75 receiving hemoglobin A1c (HbA1C) testing during the measurement year
A1c Control	Percentage of continuously enrolled members with diabetes (Type 1 and Type 2) age 18–75 whose HbA1c was poorly controlled (>9.5%) during the measurement year (subtracted from 100% to make higher rates indicate better performance)
Eye Exam	Percentage of continuously enrolled members with diabetes (Type 1 and Type 2) age 18–75 receiving an eye exam during the measurement year
Lipid Control	Percentage of continuously enrolled members with diabetes (Type 1 and Type 2) age 18–75 whose most recent LDL-C level was less than 130 mg/dL during the measurement year
Nephropathy	Percentage of continuously enrolled members with diabetes (Type 1 and Type 2) age 18–75 who were monitored for nephropathy during the measurement year
Claims Processing	Member satisfaction rating on claims processing during the 12-month continuous enrollment period (0–100 scale)
Getting Care Quickly	Member satisfaction rating on how quickly patients were able to obtain care during the 12-month continuous enrollment period (0–100 scale)
Doctor Communication	Member satisfaction rating on how well doctors communicated with patients during the 12-month continuous enrollment period (0–100 scale)
Staff Helpful	Member satisfaction rating on how their practitioner office staff were courteous and helpful during the 12-month continuous enrollment period (0–100 scale)
Explanatory variables
Plan–Pair Overlap	Percentage of physicians who appear in both plans' networks
Plans per Physician	Average number of health plans that the physicians in a given plan have a contract with
For-Profit	=1 if the plan has for-profit status; 0 if nonprofit
Both Plans NP	=1 if both plans have nonprofit status; 0 otherwise
One NP One FP	=1 if one plan has for-profit status and the other has nonprofit status; 0 otherwise
Both Plans FP	=1 if both plans have for-profit status; 0 otherwise (omitted category)
Plan Age >10 years	=1 if the plan is older than 10 years; 0 otherwise
Both <10 years	=1 if both plans are younger than 10 years; 0 otherwise
One <10 years One >10 years	=1 if one plan is older than 10 years and the other is younger than 10 years; 0 otherwise
Both >10 years	=1 if both plans are older than 10 years (omitted category)
Enrollment	Plan's total national enrollment size in hundred thousands
Staff/Group	Percentage of the plan's total enrollment in staff/group HMO model
Network	Percentage of the plan's total enrollment in network HMO model
IPA	Percentage of the plan's total enrollment in network IPA model
# Model Type	Number of different HMO model types employed by the plan
Case Mix	Average prevalence rates of heart disease, asthma, diabetes, and hypertension among plan enrollees
% Medicare & Medicaid	Percentage of the plan's total enrollees enrolled in Medicare & Medicaid
ACSC	Average number of hospital discharges for ambulatory care sensitive conditions per thousand Medicare enrollees across all markets served by plan
Market Share	Average market share across all markets served by plan
MDI	=0 if plan pair serves the same markets and approaches 1 as they serve different markets
Administrative Method	=1 if plan used administrative data collection method only; 0 otherwise
Method: Both Hybrid	=1 if both plans in a plan pair used hybrid data collection method; 0 otherwise (omitted category)
Method: Both Administrative	=1 if both plans in a plan pair used administrative data collection method only; 0 otherwise
Method: Different	=1 if plan pair used different data collection methods; 0 otherwise