Drug company methodologies used for reporting in the UK pharmaceutical industry payment transparency database between 2015 and 2019: A content analysis

<p dir="ltr">Pharmaceutical companies spend hundreds of millions of pounds on marketing/R&D-related payments annually to healthcare organisations and healthcare professionals. UK pharmaceutical industry self-regulatory bodies require member companies who sign up to their code of conduct to publish details of their payments. They are also required to publish the methodologies underlying these payments, namely methodological notes. This study aimed to analyse UK pharmaceutical companies' methodological notes and their adherence to the Association of the British Pharmaceutical Industry code of conduct and other relevant guidance. We conducted a content analysis of methodological notes for the years 2015, 2017 and 2019 and assessed companies' adherence to self-regulatory bodies' requirements and recommendations for methodology disclosure. Overall, 90 companies made payment disclosures in all three years, publishing 269 methodological notes. We found gaps in adherence to self-regulatory requirements. Only 3 (3.3 %) companies provided clear information for all self-regulatory body recommendations and regulations in all of their notes. Companies also varied in their approaches to important areas. For example, of the 244 notes with clear information on VAT management, 36.1 % (<i>N</i> = 88) included VAT, 30.3 % (<i>N</i> = 74) excluded VAT, and 33.6 % (<i>N</i> = 82) had multiple rules for VAT. There was evidence of widespread non-adherence to self-regulatory requirements. This suggests flaws with self-regulation and a need for greater enforcement of rules or consideration of a publicly mandated disclosure system.