Table 1

Strengths and weaknesses of case-finding tools

ToolPurposeKey strengthsKey weaknesses
ICD-9-CM External cause of injury (E-codes)Injury Surveillance and preventionStandardised for international comparison; captures adverse drug reactionsInconsistently used among hospitals; lack of clinical detail/context; variability in coding; inaccuracy
ICD-9-CM Nature of injury (N-codes)ReimbursementRoutinely collected by all hospitals; easily acquired; standardised for international comparisonLack of clinical detail/context; variability in coding; financial pressures for ‘upcoding’ or ‘downcoding’; inaccuracy
Patient Safety Indicators (PSI)Screening hospital discharge data for patient safety events to improve provider performanceMore precisely reflects exposure by restricting the denominator to exclude patients whose pre-existing conditions would probably lead to PSI events regardless of error; international utilityIncludes only 20 narrowly defined patient safety outcomes; does not capture falls or adverse drug reactions
Voluntary reporting (PSN)Identifying medical errorsEncompasses all possible errors and near misses; captures both falls and medication errorsLow reporting rate; non-representative sample
  • PSN, Patient Safety Net.