Revisiting the Perinatal Adverse Outcome Index

The challenge of sorting through copious amounts of data to find the essential information is not new. Over the years, various professions have developed key markers to highlight the essential. For example, clinicians use vital signs, accountants have bottom lines, and journalists pen pithy headlines. Perinatal safety professionals grapple with complex systems and also desire a succinct summary to measure the impact of their programs. The Adverse Outcome Index (AOI) and its cousins the Weighted Adverse Outcome Score (WAOS) and Severity index (SI), are composite scores that were designed to measure quality of perinatal care (Mann et al., 2006; Nielsen et al., 2007; Pettker et al., 2009). While a simple numerical score is enticing, the AOI only partially answers the three key questions that safety professionals must ask: Did clinicians do what they were supposed to do? Did it make a difference? Was there a plausible link between the intervention and outcome?