The phrase "all cases were ascertained" is correct and usable in written English.
It can be used in contexts where you are discussing the process of determining or confirming the details of various cases or situations.
Example: "After a thorough investigation, it was concluded that all cases were ascertained to be linked to the same source."
Alternatives: "all cases were confirmed" or "all cases were determined."
The current analysis used data from a case-cohort design (26, 27) with 1530 participants, in which a random subcohort was selected to be representative of the whole cohort, and all incident cases were ascertained.
All ASD cases were ascertained using the Autism Diagnostic Interview Revised (ADIR), the Autism Diagnostic Observation Schedule Generic (ADOS), and the DSM-IV diagnosis of pervasive developmental disorder (Neale et al., 2012, Lim et al., 2013, Liu et al., 2013).
Cases were ascertained through all surgical Units in Scotland dealing with colorectal cancer.
Cases were ascertained from all hospitals in the seven-county metropolitan area of the Twin Cities (Minneapolis and St Paul), Minnesota, and the Mayo Clinic (only cases residing in The Upper Midwest were recruited from the Mayo Clinic).
Cases were ascertained by contacting pathology departments of all 28 hospitals on Long Island and three tertiary care hospitals in New York City.
The study size was determined based on a priori sample size calculations, and cases were ascertained from provincial cancer registries, except in Quebec where hospital ascertainment was used.
Parkinson's disease cases were ascertained from the computerized Danish Hospital Register, with all hospitalizations with Parkinson's disease diagnoses registered since 1977 and all clinic visits, including outpatient clinics, since 1995.
Cases were ascertained by daily/weekly contact with pathology departments of all 28 hospitals on Long Island and three tertiary care hospitals in New York City.
Cases were ascertained by an administrator from a case register of all those screened and assessed at Cloverhill prison in the relevant period.
Cases were ascertained weekly from key clinicians in the participating centres (all maternity units in Auckland region) and from hospital birth records checked on a regular basis (by TS).
