Bastiaan Sallevelt

69 Evaluation of clarity of the STOPP/START criteria The results of stratifying the element ‘condition’ into the five descriptive components medication, disease, sign, symptom and laboratory finding are shown per STOPP/ START recommendation in Figure 2. Clarity ratings were scored on the level of condition as an element and not on the sublevel of the five descriptive components. Therefore, all components of one condition share the same colouring for their clarity. In 33 (41%) STOPP criteria and 17 (50%) START criteria, the condition consisted of more than one component. No strong associationwas found between the clarity of conditions and the nature of the descriptive components, as the clarity ratings of the condition section varied regardless of the nature of the component. However, laboratory findings used to identify the target population were discovered to have the highest clarity rating compared to other descriptive components in STOPP recommendations; 9 out of 13 laboratory-based conditions had a high clarity rating (>67.7%). Discussion Main findings In this study, we evaluated the clinical applicability of STOPP/START criteria in daily patient care by assessing the clarity of singular criteria. We found that 13 out of 80 STOPP and 4 out of 34 START criteria had a high clarity rating for the three elements action, condition and explanation. To improve clarity of recommendations, element-specific strategies can be formulated (Table 1). Actions were considered unclear if recommendations included non-explicitly specified drug classes (e.g. ‘anticholinergics’). To improve clear description of the action (what and how) we advise to specify drugs at an individual substance level. The addition of how to start or stop a drug (immediately versus gradually, including monitoring guidelines and deprescribing schedules), route of administration and dosage were considered necessary for some actions to further improve clarity. The definition of the condition (the when) had the lowest average clarity rating in both START and STOPP. Low clarity ratings for conditions resulted from insufficient distinctiveness in the identification of patients for whom recommendations do or do not apply. Conditions were described by medication, diseases, signs, symptoms and laboratory findings. To increase the clarity of the conditions, laboratory findings and signs have the highest potential to be optimized by adding statements about clear cut-off levels (e.g. ‘potassium >5.0 mmol/L’ instead of ‘hyperkalaemia’) and measurements (e.g. ‘systolic blood pressure >160 mmHg’ instead of ‘uncontrolled severe hypertension’). For conditions defined by medication use, the same improvements as suggested for actions apply. In some cases even a description on 2