RAND Health Insurance Experiment

Description

'The RAND Health Insurance Experiment (RAND HIE) was a comprehensive study of health care cost, utilization and outcome in the United States. It is the only randomized study of health insurance, and the only study which can give definitive evidence as to the causal effects of different health insurance plans. [...] Although the fieldwork of the study was conducted between 1974 and 1982, the results are still highly relevant, since RAND HIE is the only study which can make causal statements.' (Wikipedia, RAND Health Insurance Experiment, https://en.wikipedia.org/w/index.php?title=RAND_Health_Insurance_Experiment&oldid=110166949, accessed April 8, 2007).

Usage

data(RandHIE)

Format

This data frame contains the following columns:

plan

HIE plan number.

site

Participant's place of residence when the participant was initially enrolled.

coins

Coinsurance rate.

tookphys

Took baseline physical.

year

Study year.

zper

Person identifier.

black

1 if race of household head is black.

income

Family income.

xage

Age in years.

female

1 if person is female.

educdec

Education of household head in years.

time

Time eligible during the year.

outpdol

Outpatient expenses: all covered outpatient medical services excluding dental care, outpatient psychotherapy, outpatient drugs or supplies.

drugdol

Drug expenses: all covered outpatient and dental drugs.

suppdol

Supply expenses: all covered outpatient supplies including dental.

mentdol

Psychotherapy expenses: all covered outpatient psychotherapy services including injections excluding charges for visits in excess of 52 per year, prescription drugs, and inpatient care.

inpdol

Inpatient expenses: all covered inpatient expenses in a hospital, mental hospital, or nursing home, excluding outpatient care and renal dialysis.

meddol

Medical expenses: all covered inpatient and outpatient services, including drugs, supplies, and inpatient costs of newborns excluding dental care and outpatient psychotherapy.

totadm

Hospital admissions: annual number of covered hospitalizations.

inpmis

Incomplete Hospital Records: missing inpatient records.

mentvis

Psychotherapy visits: indicates the annual number of outpatient visits for psychotherapy. It includes billed visits only. The limit was 52 covered visits per person per year. The count includes an initial visit to a psychiatrist or psychologist.

mdvis

Face-to-Face visits to physicians: annual covered outpatient visits with physician providers (excludes dental, psychotherapy, and radiology/anesthesiology/pathology-only visits).

notmdvis

Face-to-Face visits to nonphysicians: annual covered outpatient visits with nonphysician providers such as speech and physical therapists, chiropractors, podiatrists, acupuncturists, Christian Science etc. (excludes dental, healers, psychotherapy, and radiology/anesthesiology/pathology-only visits).

num

Family size.

mhi

Mental health index.

disea

Number of chronic diseases.

physlm

Physical limitations.

ghindx

General health index.

mdeoff

Maximum expenditure offer.

pioff

Participation incentive payment.

child

1 if age is less than 18 years.

fchild

female * child.

lfam

log of num (family size).

lpi

log of pioff (participation incentive payment).

idp

1 if individual deductible plan.

logc

log(coins+1).

fmde

0 if idp=1, ln(max(1,mdeoff/(0.01*coins))) otherwise.

hlthg

1 if self-rated health is good – baseline is excellent self-rated health.

hlthf

1 if self-rated health is fair – baseline is excellent self-rated health.

hlthp

1 if self-rated health is poor – baseline is excellent self-rated health.

xghindx

ghindx (general healt index) with imputations of missing values.

linc

log of income (family income).

lnum

log of num (family size).

lnmeddol

log of meddol (medical expenses).

binexp

1 if meddol > 0.

Source

Data sets of Cameron and Trivedi (2005), http://cameron.econ.ucdavis.edu/mmabook/mmadata.html.

Additional information of variables from Table 20.4 of Cameron and Trivedi (2005) and from Newhouse (1999).

References

Cameron, A. C. and Trivedi, P. K. (2005) Microeconometrics: Methods and Applications, Cambridge University Press.

Newhouse, J. P. (1999) RAND Health Insurance Experiment [in Metropolitan and Non-Metropolitan Areas of the United States], 1974–1982, ICPSR Inter-university Consortium for Political and Social Research, Aggregated Claims Series, Volume 1: Codebook for Fee-for-Service Annual Expenditures and Visit Counts, ICPSR 6439.

Wikipedia, RAND Health Insurance Experiment, https://en.wikipedia.org/wiki/RAND_Health_Insurance_Experiment.

Examples

## Cameron and Trivedi (2005): Section 16.6, page 553ff
data( RandHIE )
subsample <- RandHIE$year == 2 & !is.na( RandHIE$educdec )
selectEq <- binexp ~ logc + idp + lpi + fmde + physlm + disea +
   hlthg + hlthf + hlthp + linc + lfam + educdec + xage + female +
   child + fchild + black
outcomeEq <- lnmeddol ~ logc + idp + lpi + fmde + physlm + disea +
   hlthg + hlthf + hlthp + linc + lfam + educdec + xage + female +
   child + fchild + black
# ML estimation
cameron <- selection( selectEq, outcomeEq, data = RandHIE[ subsample, ] )
summary( cameron )