Why we need to collect full identifiers for the perinatal death cases reported
We are collecting full personal identifiers as part of the MBRRACE-UK data collection for stillbirths and infant deaths. This is for several reasons which are mainly related to the fact that we will be calculating mortality rates for Units and networks and to enable us to adjust the mortality rates for population characteristic and case-mix features. It is particularly important that we calculate adjusted rates because we know some Units deal with high risk cases and if we just provide crude unadjusted mortality rates these Units will have spuriously high mortality rates and appear as outliers simply because they deal with high risk patients and not because they provide poor quality care.
We therefore need the full identifiers for the following reasons:
- We need to be certain that we do not have accidental duplicates in the system which would spuriously inflate Unit mortality rates and the only way to identify these is with personal identifiers.
- We need to link the data we collect from Units to the national birth and death registration data. We need to do this to ensure that deaths have not been missed and also so that we have denominators for the calculation of rates which can be adjusted for population characteristics (eg deprivation derived from an indicator based on postcode) and case-mix factors (eg maternal age). It is therefore essential for us to know in the national dataset when a birth also resulted in a death and in which Unit that occurred. Again a range of full identifiers is needed to do this linkage accurately across the whole of the UK where there are over 800,000 births per year.
- Finally if we need to follow up queries with particular Units we need a clear unambiguous way of identifying the woman/baby we are referring to.
Security and approvals
The identifiable data items are stored within our electronic data system separately from the clinical information and are encrypted whilst stored. We have developed our data systems with a very high level of security.
For England and Wales MBRRACE-UK has Secretary of State for Health approval through the National Information Governance Board (NIGB) processes (and it successor organisation the Confidentiality Advisory Group at the Health Research Authority) to collect fully identifiable data (ECC 5-05 (f)/2012). We have also completed the NHS IGToolkit (8J017) with 100% success.
For Scotland we have approval from the NHS Scotland Caldicott Guardian to collect fully identifiable data; this process of approval included a full review and approval of our security and data handling procedures.
For Northern Ireland special arrangements are in place whereby fully identifiable data are being collected by the NIMACH office.