What the "O" in STOPP Represents
The "O" in STOPP stands for "Older" (Screening Tool of Older Persons' Prescriptions), and the specific action performed is systematically screening all medications prescribed to older adults (typically ≥65 years) to identify potentially inappropriate medications (PIMs) that should be stopped or avoided. 1, 2
Understanding STOPP as a Screening Tool
STOPP is designed to identify medications that are potentially inappropriate for older adults by applying explicit, systems-based criteria during medication review. 2, 3 The tool comprises 65-134 criteria (depending on version) organized by physiological system to facilitate systematic evaluation. 1, 2
The Core Action: Systematic Medication Screening
When applying STOPP, the clinician performs the following specific actions:
Review all prescription medications, over-the-counter drugs, herbal products, and supplements at every care transition (hospital admission, ICU transfer, discharge, clinic visits). 4, 1
Apply the explicit STOPP criteria systematically by physiological system to identify PIMs, including drug-disease interactions, drug-drug interactions, duplicate therapies, and medications requiring dose adjustment for renal function. 1, 2
Identify medications without appropriate clinical indication, as this represents the most common type of STOPP criterion violation. 5
Flag high-risk medications such as benzodiazepines (linked to cognitive impairment, delirium, falls, fractures), NSAIDs (associated with GI bleeding, acute kidney injury, heart failure exacerbation), and anticholinergics. 4, 1
Clinical Performance and Validation
STOPP demonstrates superior performance compared to Beers criteria in detecting PIMs that cause hospital admissions. 6 In a prospective study of 715 acute hospital admissions, STOPP identified 336 PIMs affecting 35% of patients, with STOPP-related PIMs contributing to 11.5% of all admissions—significantly higher than the 6% identified by Beers criteria. 6
The tool has favorable inter-rater reliability with a kappa-coefficient of 0.75, indicating substantial agreement among clinicians applying the criteria. 2
Integration with START Criteria
STOPP is typically used in conjunction with START (Screening Tool to Alert to Right Treatment) to address both inappropriate prescribing and prescribing omissions. 1, 2 While STOPP identifies medications to stop, START identifies 22-34 evidence-based medications that should be considered for addition based on documented conditions. 1, 2
Common Pitfalls to Avoid
Do not apply STOPP criteria rigidly without considering patient-specific factors including functional status, cognitive status, multimorbidity burden, life expectancy, and individual goals of care. 1, 3
Avoid relying solely on chronological age when making prescribing decisions; incorporate functional and cognitive assessments. 1
Do not ignore the need for face-to-face interaction between clinicians and trained personnel (typically pharmacists) to explain and qualify specific STOPP recommendations for individual patients, as this interaction is essential for implementation. 3
Recognize that approximately 35% of STOPP/START criteria cannot be computerized due to lack of information on disease severity and insufficient diagnostic code coverage, requiring clinical judgment. 7