Bastiaan Sallevelt

113 Conversion of STOPP/START version 2 into coded algorithms Introduction Along with the rapidly aging population, the prevalence of multimorbidity and polypharmacy is increasing [1,2]. Polypharmacy increases the risk of inappropriate medications and is associated with adverse drug reactions (ADRs), poorer drug adherence, higher health care costs, more emergency department visits, hospital admissions and overall mortality [3,4]. Several implicit (judgement based) and expliwcit (criterion based) tools have been developed to detect inappropriate prescribing in multimorbid older people [5–7]. It appears to be challenging to incorporate these tools into daily clinical practice. Since the publication of the first version of STOPP (Screening Tool of Older Person’s Prescriptions) and START (Screening Tool to Alert doctors to Right Treatment) criteria in 2008, this explicit screening tool to detect potentially inappropriate prescribing (PIP) in older people has become the European alternative for the American Beers list, with a higher sensitivity for identifying ADR associated potentially inappropriate medications (PIMs) [10-8]. When applied as an intervention, STOPP/START criteria significantly improved medication appropriateness in older patients admitted for acute illnesses and significantly reduced ADRs [11,12]. In 2015, the STOPP/START criteria were updated resulting in a 31% increase in the total number of criteria compared to version 1 [13]. Due to the extensiveness of the list, currently comprising 114 criteria, there has been growing interest in developing STOPP/START software applications for clinical decision support systems (CDSS) as well as research studies in large databases [14–16]. More recently, the PIM-check was developed [17].This international electronic prescription screening checklist was designed to detect PIMs in internal medicine patients. This checklist includes 160 statements in 17 medical domains and 56 pathologies. Comparison of PIM-Check and nondigital version of STOPP/START criteria applied to internal medicine patients revealed a substantially shorter screening time for PIM-Check compared to STOPP/START (4 vs 10min) due to its electronic interface [18]. This emphasizes the need for digitalization of (explicit) screening tools. Nearly half of the detected PIMs, however, were judged to be nonclinically relevant for both tools. The consensus based specification of STOPP/START criteria version 1 implemented in a CDSS, improved the effectiveness of a medication review, expressed as an increase in appropriate decisions and a decrease in inappropriate decisions in accordance with an expert panel, compared to a traditional (non-digitalized) medication review [19,20]. 2