I want to know key information about MOSS
What is a safety signal system?
Higher than expected levels of adverse events can indicate a decline in safe care.
Safety signal systems monitor real time trends in data, so that timely responses can be actioned to prevent further adverse outcomes.
Is MOSS targeted on a particular area of maternity care?
Yes. MOSS is targeted on potential safety issues in intrapartum care.
This is due to the outcome measures chosen. Term events (stillbirth and neonatal death up to 28 days) have been selected as they are more commonly associated with standards of intrapartum care not being met.
Correspondingly, the MOSS critical safety check is focussed on intrapartum care. In future, we hope to add term brain injuries to MOSS.
How will MOSS help improve outcomes?
Safety signal monitoring systems are known to improve outcomes in health care and non-health care settings especially where the risks to health or safety are significant.
Children’s cardiac surgery and paediatric intensive care already use safety signal systems with positive effects.
Use of MOSS will be mandated and incorporated into routine safety governance processes at unit and trust board level and all other levels of the Perinatal Quality Oversight Model – ICB, regionally and nationally.
Some MOSS data will be made publicly available providing further transparency of Trust actions taken in response to signals.
Does MOSS show safety outliers?
No. MOSS provides an indication of potential safety issues only.
This is because there might be reasons other than poor standards in care for an event or signal occurring.
It is therefore the critical safety check and governance processes which a MOSS signal triggers which determines whether a safety issue is genuine.
How will I know if/when my site has signalled?
An automatic email will be sent from the MOSS system when a site has signalled.
The email will be sent to all registered users associated with the site. This may include colleagues from the trust, ICB and region.
The email will request that the perinatal leadership team carries out a critical safety check (as described in Annex 1) which should be completed approved and shared with ICB/regional colleagues within 8 working days of a signal.
If a signal is received over the weekend, the timeline starts on the next working day.
Why is MOSS different to other dashboards?
Despite wide ranging data collection and improvement programmes in maternity care, we have still not yet achieved sufficient improvement in outcomes.
The design of MOSS is to focus on near real-time term outcomes such as stillbirths and neonatal deaths, which are more likely to be due to suboptimal care.
A signal in MOSS will trigger a rapid response by maternity services, as given in the standard operating procedures and Annex 1.
How is MOSS different from investigations?
MOSS is part of a critical safety management system focused on timely, proactive prevention of harm.
Investigations, in contrast, are retrospective, analysing individual events to understand contributing factors and answer questions.
How should MOSS be governed?
MOSS signals and responses to critical safety checks should be reported and governed under the Perinatal Quality Oversight Model (PQOM) – formerly known as the Perinatal Quality Surveillance Model (PQSM) – which has been in place since April 2020.
The PQOM uses data and intelligence to identify services with safety issues and target the appropriate support and operates at ICB, regional and national level.
Do I need to submit to any new data collections for MOSS?
No. MOSS will use existing routinely collected data to minimise burden on trusts.
Data will be drawn from the Personal Demographics Service (PDS) and, in a future update, the Submit a Perinatal Event Notification service (SPEN).
Both PDS and SPEN provide data to NHS England in near-real time to aid timely monitoring.
Does my team need to have significant experience in data to understand this system?
Signal systems intend to be very easy to understand by those using the system, so there will be no requirement for any statistical expertise within the team to understand it.
Teams simply need to recognise a signal and carry out the critical safety check.
The national team will provide support to maternity services and can be contacted via email at england.moss@nhs.net.
I want to know who can use MOSS
Who will have access to MOSS?
Colleagues working in or supporting maternity services will be able to request access to MOSS.
This includes colleagues at trust, ICB, regional and national level.
At trust level, the following colleagues should register to access MOSS at a minimum:
- The perinatal leadership team at each trust site, to include:
- director of midwifery (or head of midwifery if none appointed)
- operational lead of the maternity service
- obstetric lead (clinical director/head of service)
- neonatal lead (nursing/medical)
- Accountable trust board executives to include:
- executive trust board safety champion
- chief medical officer
- chief nurse
- Maternity and neonatal voices partnership lead
At ICB level, the executive with responsibility for maternity and neonatal services and director of quality should register, at a minimum.
At regional level, the regional chief nurse, midwife, obstetrician and medical director should register at a minimum.
Maternity improvement advisors should register for access to MOSS to as part of supporting trusts enrolled onto the Maternity Safety Support Programme.
Other trust, ICB, regional and national colleagues with a remit over supporting perinatal quality/governance should also register for access.
Can MOSS be used by neonatal services?
MOSS can be viewed by neonatal services and operational delivery networks.
MOSS focuses on potential safety issues in intrapartum care; however, neonatal leads may play a role in completing the MOSS critical safety check with their perinatal leadership team colleagues (see Annex 1).
One of the operational checks includes achieving 90% of attendance in each relevant staff group (as per Maternity Incentive Scheme guidance) with neonatal resuscitation training.
Neonatal services are also encouraged to use the MBRRACE-UK real time data monitoring tool – see further information below.
I want to know more about the critical safety check
What is the ‘critical safety check’ and how is it different from what we already do?
The MOSS critical safety check (Annex 1) is operationally focused. It contains critical safety processes that underpin safe intrapartum care.
The check should be carried out by the perinatal leadership team every time a maternity unit signals.
It provides a structured, rapid process to confirm whether there are potential intrapartum safety issues and identifies early actions to prevent further harm.
The guidance says action needs to be led by the perinatal leadership team in response to a signal. Can the team delegate these responsibilities instead?
No. It is vital that the check of potentially critical safety issues in intrapartum care is led and co-ordinated by the perinatal leadership team, and that the team is regularly engaged with what is happening on the intrapartum ward.
Individual tasks may be delegated, such as gathering data to support parts of the response; however, the perinatal leadership team must own the overall, completed response.
Will the ICB or region get involved when there is a signal?
Not immediately. The trust site perinatal leadership team must first complete the critical safety check within 8 working days.
Once approved by an accountable trust board executive*, it is shared with ICB colleagues† for oversight, and with regional colleagues‡ for awareness; or with regional colleagues only, if oversight responsibilities have been transferred (see important note in standard operating procedures).
* chief nurse, chief medical officer or executive trust board safety champion
† ICB executive with responsibility for maternity and neonatal services or director of quality
‡ regional chief nurse, midwife, obstetrician and medical director
How can perinatal leadership teams complete the check within 8 working days?
Completing the check quickly ensures timely action if risks are identified.
Teams should have pre-agreed local processes and annual preparedness checks in place to support a swift response.
What is the role of trust boards?
Accountable trust board executives should inform the trust board of safety issues found from critical safety checks, which should be discussed as an agenda item at the next public trust board meeting.
Accountable trust board executives include the chief nurse, chief medical officer and executive trust board safety champion.
Trust boards should provide oversight and active engagement to ensure that any plans made to address safety issues make progress and are completed at the required speed.
I want to know more about signals and how MOSS data is analysed
What method is used to generate a signal?
Signals are generated using cumulative sum (CUSUM) methodology, which has been shown to work in children’s cardiac surgery and other non-healthcare industries.
First, we calculate a national reference rate by using the total number of term stillbirths and neonatal deaths divided by the total number of term births in England, over a 3-year rolling period.
Then, we apply this output to the total number of annual term births in any given site. This produces an ‘expected’ annual rate for term events in any given site.
This expected rate is divided by 12 to produce a monthly ‘expected’ rate for a site.
Signals occur when term events that are logged in near real time, double the ‘expected’ rate and are based on the level of confidence that these are not down to chance.
How can I tell what events contributed towards a signal in MOSS?
Events that have contributed towards signals are shown in the excess events chart (see hover text) and a table of events beneath the charts in MOSS.
What is the difference between a level 1 and a level 2 signal?
Levels 1 and 2 are thresholds in the Maternity Outcomes Signal chart which relate to the level of statistical confidence that the rate of events at site level has doubled compared to the national reference rate.
Breaching the level 1 threshold represents a 95% statistical confidence that the site rate has at least doubled compared to the national reference rate.
Breaching level 2 represents a 99% statistical confidence.
As there is greater confidence that level 2 signals reflect a true doubling in the rate of events, the standard operating procedures outline an additional peer review of the completed critical safety check.
This will provide an external check and challenge of the safety of the intrapartum service that has signalled.
Why do you use a 3-year rolling reference rate? How does this account for potentially falling birth rates in some maternity services?
MOSS requires data covering a static time period to calculate its reference rate, which is used to generate signals.
When developing MOSS, 2 broad reference rate approaches were tested:
- Using a static reference period that is not updated
- For example, a reference rate based on a fixed period of data.
- This does not ‘undo’ historical signals via having a reference rate that changes.
- However, it would not account for trends and changes in the number of births over time and so would become outdated.
- Using a reference period that updates periodically
- For example, a reference rate that is refreshed every X number of years and is based on an X year period of data.
- This allows the reference rate to account for changes in the number of births, but the timing of refreshes should minimise the ‘undoing’ of historical signals (that is, where MOSS generates a signal using one reference rate but not another).
Based on expert input, analysis and testing, a 3-year rolling reference was chosen.
This allows MOSS to account for trends in the number of births with good timeliness and minimise the ‘undoing’ of historical signals via reference rates changing (as would be the case if, say, a single-year reference rate was used).
How often does data in MOSS update?
MOSS updates on daily basis.
How is MOSS different to the MBRRACE-UK real time data monitoring tool?
The MBRRACE-UK real time data monitoring tool and MOSS should be viewed as complementary tools and, while they are both capable of monitoring real time safety trends to show unusual levels of activity, there are various differences between them including the outcomes used, statistical methods, charts presented and filters.
The key difference is that the MBRRACE-UK real time data monitoring tool uses all perinatal events (both term and preterm stillbirths and neonatal deaths) and displays trends based on the changes in frequency of events.
As such, a neonatal unit (in addition to maternity) may find this tool helpful to monitor safety trends in real time.
In comparison, MOSS uses term events only and uses cumulative sum methodology to generate signals. MOSS is to be used by intrapartum maternity services only.
Are sites’ events shown by where babies were delivered or where they died?
MOSS shows events by trust site based on where babies were delivered.
This is to help target MOSS on potential safety issues in intrapartum care.
I want to know why certain data was not included in MOSS
Why have you not used intrapartum stillbirths if MOSS is targeted towards potential safety concerns in intrapartum care?
There is much variation in how intrapartum stillbirths are recorded across maternity providers.
We do not yet have the requisite data quality to use intrapartum stillbirths specifically in MOSS.
MOSS currently uses all term stillbirths.
Why does MOSS not measure preterm neonatal deaths or stillbirths?
The rationale for not including preterm deaths and stillbirths in MOSS is that suboptimal care is not a major causative factor.
In addition, variation in the rates and complexity of preterm births could drive differences in outcomes between units which reflect the population giving birth rather than the safety of care.
MOSS must remain sufficiently sensitive to generate accurate signals of potential suboptimal maternity care during labour – a key factor in relation to poor outcomes.
For information, near real time data on all perinatal death (term and preterm) is available via the MBRRACE-UK real time data monitoring tool.
Why isn’t MOSS signal data adjusted for congenital anomalies?
We have decided not to adjust for congenital anomalies as suboptimal intrapartum care and therefore signals of potential safety issues can still occur in these cases.
It is acknowledged that sites that are NICU plus cardiac surgery centres may generate more frequent signals, due to caring for babies with congenital anomalies that have a known high risk of stillbirth or neonatal death.
If signals occur, perinatal leadership teams should remain curious and still proceed with the critical safety check as part of good practice
What if MOSS signals all the time – can we trust it?
MOSS has been validated to avoid over-generation of signals.
The critical safety check following a signal may prove reassuring, but this is expected in safety monitoring. Like a smoke or car alarm, the system is designed to err on the side of safety assurance.
MOSS does not replace individual case investigations which should carry on as normal.
Perinatal leadership teams in maternity services should remain curious and always proceed with the critical safety check following signals as part of good practice.
Why have you not used variables such as ethnicity and deprivation to show signals of potential safety issues?
Adjusting the data used in MOSS by demographic factors such as ethnicity and deprivation has been considered, given there is known variation in maternity and neonatal outcomes across different groups within the population.
However, building such an adjustment into MOSS could lead to a reduction in the sensitivity of signal generation (for example by weighting down certain events so they do not signal), meaning potential safety issues are not detected.
Furthermore, the data fields currently feeding into MOSS would not allow for a sufficient adjustment to be constructed.
Signals in MOSS are to prompt a critical safety check and do not necessarily mean there are safety issues in a maternity unit, which is determined by the output of the check and governance review.
As such, we do not currently adjust MOSS signals for demographic variables, basing signals on all events equally.
However, this is something that will continue to be monitored during iterations of MOSS.
How complete is the data that MOSS uses?
MOSS requires data that is both highly complete and very timely, so it can generate accurate, timely signals about potential safety issues in maternity care.
Data sources for MOSS have been selected accordingly.
MOSS currently uses data from the Personal Demographics Service (PDS).
PDS is updated in near-real time and our assessments indicate it provides a high level of completeness and quality suitable for signal generation.
However, if you do have concerns about your site’s data, please contact england.moss@nhs.net.
Why are the thresholds on the CUSUM charts different for different trust sites? Why do the thresholds move every year?
The thresholds differ for each trust site as, in addition to being dependent on the different levels of statistical confidence for Level 1 and 2 signals, they also depend on the expected number of events for each site.
The expected number of events is calculated by multiplying the national reference rate by the average number of births for each site, leading to different thresholds for different sites.
As the national reference rate is recalculated every year, this alters the expected number of events at each site, which in turn alters the calculation of the thresholds.
This results in thresholds shifting in January of each year.
I want to know who I can contact if I have issues or further questions
How can I contact the team in charge of MOSS for further information on MOSS or the standard operating procedures?
Please email england.moss@nhs.net and we will aim to respond as soon as possible.
The data for our site is incorrect – who do I contact?
Please contact england.moss@nhs.net if your trust site’s data does not look correct.
We will be in touch to discuss further and any next steps to rectify the issue.
I have technical or access issues with using MOSS – who do I contact?
Please email england.datavizfunction@nhs.net.
Publication reference: PRN02098_vi