Bastiaan Sallevelt

62 CHAPTER 2.2 Methods STOPP/START criteria The STOPP/START criteria were first published in 2008 and have been updated in 2015 to STOPP/START version 2 [17]. STOPP/START is a product of two Delphi rounds by 19 experts from 13 European countries. For this study, the supplementary data of the corrigendum of the STOPP/START criteria version 2 as published in November 2017 were used [18]. STOPP/START version 2 consists of a list of 80 Potentially Inappropriate Medications (PIMs, STOPP criteria) and 34 Potential Prescribing Omissions (PPOs, START criteria). Clarity assessment The AGREE II Instrument and GUIDE-Mwere used to develop a framework to assess the clarity of language used in STOPP/START. AGREE II Instrument is an internationally validated tool to rate the quality of CPGs, developed by the Appraisal of Guidelines for Research & Evaluation (AGREE) Consortium [19]. In addition to the AGREE II Instrument, AGREE developed a Guideline Implementability Decision Excellence Model (GUIDE-M) [20]. This model identifies ‘communicating content’ as a core tactic for CPG implementability. Obviously, language is an important domain of this tactic. The language subdomain promotes a clear, simple, and persuasive message. The relevant part of the AGREE II Instrument (‘clarity of presentation’, domain 4, item 15) states that recommendations should be ‘specific and unambiguous’, which is defined as ‘a concrete and precise description of which option is appropriate for which situation and for what population group’. In line with this statement and the corresponding section of the AGREE II Instrument, three elements were identified that influence the clarity of recommendations: • Action: description of the recommended action, i.e. what to do and how to act? • Condition: identification of the relevant target population and statements about patients or conditions for whom the recommendations would apply or not apply, i.e. when? • Explanation: identification of the intent or purpose of the recommended action, i.e. why? In order to quantify the clarity of STOPP/START criteria, the three elements of each recommendation were rated independently on a 7-point Likert scale by a panel