Main findings
Eighty COS studies have been registered covering a wide range of
clinical issues in women’s and neonatal health. Only a minority (30%)
had published a protocol and of these only 17% were assessed to meet
all COS-STAP criteria. Twenty COS have been completed; only four and
three met the COS-STAD and COST-STAR recommendations respectively.
Studies where criteria were not met were primarily due to variation in
patient engagement, outcome selection and the Delphi process.