“…Consistent with previous studies using both versions 1 and 2 of the STOPP criteria, this study identified a significant association between polypharmacy (>5 medications) and prescription of at least one PIM [25,30,32,33,[35][36][37][38][39][40][41][42][43][44][45]. The association between PPO occurrence and polypharmacy identified in this study has been less consistently reported elsewhere [33,36,37,46]. It is possible that prescribers may regard an increased medication burden and the resulting increased risk of adverse drug reactions as a barrier to the addition of further medication despite the potential for benefit, thus creating a 'treatment-risk paradox' [47].…”