As per the NHSI website;
The attached Serious Incident framework describes the process and procedures to help ensure serious incidents are identified correctly, investigated thoroughly and, most importantly, learned from to prevent the likelihood of similar incidents happening again.
This framework is designed to inform staff providing and commissioning NHS funded services in England who may be involved in identifying, investigating or managing a serious incident. It is relevant to all NHS-funded care in the primary, community, secondary and tertiary sectors. This includes private sector organisations providing NHS-funded services.
Investigations carried out under this framework are conducted for the purposes of learning to prevent recurrence.