Results
We identified 284 unique authors from the 10 CPGs published by the Japanese Society of Neurology between 2016 and 2020. Among these authors, 34 (12.0%) contributed to the development of two different CPGs, 241 (84.9%) were male physicians, and 73 (25.7%) held full professorships at their affiliated universities. Of these authors, 236 (83.1%) received one or more personal payments from pharmaceutical companies between 2016 and 2020 (Table 1). The total amount of payments to 273 authors was $13.9 million, encompassing 14,596 transactions over the five years. The mean and median personal payments per author were $49,274 (SD: $81,146) and $15,255 (IQR: $1,138–$58,737), respectively. Over the five years, 28.2%, 16.2%, and 4.6% of authors received more than $50,000, $100,000, and $250,000, respectively. All 10 CPG chairpersons and 9 vice chairpersons received personal payments, with a mean of $118,450 (standard deviation: $153,378). The mean payment amounts were significantly higher for CPG chairs and vice chairpersons than for other authors ($118,450 vs. $44,593, p<0.001 in the Mann-Whitney U test).
Table 2 describes the payments by guideline. Of the 10 CPGs, all had more than 50% of their authors receiving personal payments, with percentages ranging from 72.6% to 100%. All authors of the spinocerebellar degeneration and multiple system atrophy CPG received payments from the companies. The mean personal payments were highest for the Parkinson’s disease CPG ($160,441), followed by epilepsy ($78,110), dementia ($72,431), and spinocerebellar degeneration and multiple system atrophy ($44,989).