Methods
Utilizing the publicly available payment database,10this analysis examined all personal payments to cardiologists from
JPMA-affiliated pharmaceutical companies from 2016 to 2019. We included
all cardiologists board-certified by the Japanese Circulation Society
(JCS) as of September 2021. The JCS, established in 1935, is the sole
professional body board-certifying cardiologists since 1989. As of the
specified date, we identified 15,048 board-certified cardiologists from
the JCS webpage. The JPMA only requires its member companies to disclose
personal payments to individual physicians for lecturing, consulting,
and writing services at individual physician level. More common payment
categories such as meals, travel, accommodations, and other gifts are
reported in aggregate, precluding individual-level
analysis.19Therefore, we searched for the
names of cardiologists and collected from the payment database only
payments to cardiologists for lectures, consulting, and writing for this
study. As payments in 2019 were the latest analyzable data at the time
of data collection, we collected payments from 2016 to 2019.
We conducted descriptive analyses including mean and median payments per
cardiologist and the proportion of cardiologists receiving payments. The
concentration of payments among cardiologists was assessed using the
Gini index, as in previous studies.20-22 Furthermore,
we examined trends in the number of cardiologists receiving payments and
the payment amounts from 2016 to 2019 using generalized estimating
equation (GEE) models. To adjust for highly skewed distribution of
payments, we used a log-linked GEE model with a Poisson distribution for
the number of cardiologists receiving payments and a negative binomial
GEE model for payments per cardiologist, as conducted in previous
studies.11,13,16,19,23 For trend analysis, we adjusted
for inflation, converting all payment values to 2019 Japanese yen value.
Given that all data used in this study were publicly available and met
the definition of non-human subjects research, institutional review
board approval was not required in Japan.