Predictive Risk Modelling for Integrated Care: a Structured Review
∗
Mohsen Mesgarpour∗ , Thierry Chaussalet∗ , Philip Worrall∗ and Salma Chahed∗
Health and Social Care Modelling Group, Faculty of Science and Technology, University of Westminster, London, UK
Email: mohsen.mesgarpour@gmail.com, hscmg@westminster.ac.uk
Abstract—If patients at risk of admission or readmission
to hospital or other forms of care could be identified and
offered suitable early interventions then their lives and longterm health may be improved by reducing the chances of future
admission or readmission to care, and hopefully, their cost of
care reduced.
Considerable work has been carried out in this subject area
especially in the USA and the UK. This has led for instance
to the development of tools such as PARR, PARR-30, and
the Combined Predictive Model for prediction of emergency
readmission or admission to acute care.
Here we perform a structured review the academic and grey
literature on predictive risk tools for social care utilisation, as
well as admission and readmission to general hospitals and
psychiatric hospitals. This is the first phase of a project in
partnership with Docobo Ltd and funded by Innovate UK,
in which we seek to develop novel predictive risk tools and
dashboards to assist commissioners in Clinical Commissioning
Groups with the triangulation of the intelligence available from
routinely collected data to optimise integrated care and better
understand the complex needs of individuals.
Keywords-Admission, Readmission, Hospital, Social Care,
Mental Care, Predictive Risk, Integrated Care
I. I NTRODUCTION
After the controversies of the 2012 Heath and Social
Care Act [1], the focus has been on the development of
new predictive models for integrated care. The strategic
five-year forward view of the NHS [2] outlines multiple
delivery models, which are aimed to improve care and
drive productivity by aligning and integrating hospital care,
social care, community care, mental health and primary
care. The main focus is on two models: Primary and Acute
Care Systems, which is developed for hospitals, and Multispeciality Community Providers, which is lead by primary
care. The NHS, Commissioners and other providers cooperatively design services based on a model of cohort-specific
integrated care with their own exemplars, risks, benefits
and transition cost. Also, service providers will become
responsible for a capitated budget for local population health
and community services.
This structured review was carried out by the Health and
Social Care Modelling Group (HSCMG) at the University
of Westminster in partnership with Docobo Ltd to review
recent predictive modellings for social care utilisation and
admission and readmission to general hospitals and psychiatric hospitals. The focus of this review was on generic risk
factors and risk prediction approaches to identify people who
are at risk of poorer health outcome and enable efficient
integrated care delivery.
Based on the rapid review of both gray and peer-reviewed
literature using MEDLINE, Web of Science and Google
Scholar, we identified eighty-three studies after removing
duplicates and irrelevant publications. The review was conducted using records until September 2015, with search
terms including admission, readmission, hospital, General
Practitioner (GP), inpatient, outpatient, social care, mental
(psychological or psychiatric), A&E (emergency department
or emergency room) and comorbidity (morbidity, multimorbidity, Charlson or Elixhauser). The majority of these
researches were carried out in the United Kingdom (UK)
and North America.
The main content is divided into five sections. Firstly,
the predictive modelling problem is defined. Afterwards, the
predictive models in social care, mental care and hospital
are reviewed. Thereafter, the correlated variables are summarised. Furthermore, main risk scoring methods are briefly
reviewed. Finally, a summary of this study is presented.
II. P ROBLEM
The main goal of this project was to develop and validate a
new health and social care predictive risk model for integration into the Docobo’s ARTEMUS-ICS system. ARTEMUSICS is a health analytics and risk stratification system, which
will support Integrated Care delivery by identifying complex
patients with a range of health and social needs. Also,
ARTEMUS-ICS allows multidisciplinary teams to analyse
health and utilisation information to create a holistic view
of their populations. The area covered by this research was
Horsham and Mid Sussex Clinical Commissioning Group
(CCG) and Crawley CCG, that has a population of about
345,000 registered patients, with significant variations in
population health status and deprivations [3].
III. M ODELS
A. Social Care Models
In England and Wales, social care services are provided to
individuals who are in need of practical support as a result
of illness, disability, old age or a low income. Social care
services can take a variety of forms, including but not limited
to having assistance at home to help an individual live more
independently and access to specialist equipment. In contrast
to services provided through the health care system, these
services are not necessarily available free at the point of use.
In fact, individuals are assessed to determine the degree of
their needs together with their financial circumstances and
ability to fund all or part of the care they require.
For the financial year 2014-15, it was reported that there
were over 1.8 million requests for social support from individuals not already in receipt of support. Of these requests,
72% were from individuals aged 65 years and above [4].
Overall 41% of these new requests resulted in the individual
being offered some form of social care services leading
to approximately 304,000 new ongoing low-level support
packages, 218,000 short term but intensive packages and
144,000 long-term support packages. Individuals aged 65
and over accounted for 68% of all individuals accessing
long-term support in various settings, like nursing and residential homes.
In light of the increased preventative social care strategy
in England and Wales, together with a broader international
challenge to offer care and support to older people, there
has been a shift towards a more proactive approach towards
identifying the care needs of the elderly [5]. One such
strand of research examines the factors that drive social
care usage at the individual level across a range of different
services. Such studies are often linked with the assumption
that an earlier social care intervention strategy, based on
well-defined patient characteristics, can help individuals to
live independently for longer and ultimately at a lower cost
to society as a whole.
B. Hospital Models
The main driving force behind emergency readmission [6]
is inappropriate care support for high-risk patients [7]. It was
estimated that the cost of emergency admissions to the NHS
in England is about £11 billion per year [8]. According to
a retrospective study by Clarke et al. [7], about half of the
30-day emergency readmissions were potentially preventable
between 2004 and 2010.
Emergency rates of admission for ambulatory or primary
care sensitive (ACS) and non-ACS conditions are rising
at a comparable rate, and there is no explanation for the
causes. According to a recent study by the Nuffield Trust [9],
ACS conditions make up for about 20% of all emergency
admissions (2001 to 2013).
In 2005, the Patients at Risk of Re-hospitalisation (PARR)
[10] algorithm and PARR++ software for Primary Care
Trusts were commissioned by the UK Department of health
(DoH) [8]. The objective of PARR was to classify individuals based on the risk of emergency readmission to a hospital
within a year using the inpatient data from the Hospital
Episode Statistics (HES) database. The produced PARR
model was very similar to PRISM for the NHS Wales and
SPARRA for the NHS Scotland. Then, in 2006 to address the
need for identifying patients at risk of admission to hospital,
the Combined Predictive Model (CPM) was released by the
DoH [11].
Thereafter, an upgrade from the PARR and CPM models
was commissioned by the DoH in 2011 [12], and the Patients
at Risk of Readmission within 30 days (PARR-30) model
was developed. The PARR-30 was based on a broad range
of measures used in the PARR and was aimed to predict the
risk of 30-day readmission to acute hospitals.
C. Mental Health Models
Mental health services in England have to provide care
services for children and adults with various mental health
needs, like psychosis conditions, drugs and alcohol services
and dementia. These services may be organised differently
from one local area to another and be age and/or mental
health condition specific [13].
At the end of July 2015, 922,001 people were in contact
with mental health services including 22,608 people in
psychiatric units [14]. These patients may be:
• Voluntary patients who agree to be admitted;
• Compulsory patients were admitted under the Mental
Health Act (i.e. against their wishes if it is in the
interests of their health and safety, or to protect others).
Within this context, a review report commissioned by
the DoH [15] acknowledged that the relationship between
readmission rate and quality of care can be complex, as for
severely ill patients multiple re-admissions may help them to
engage in treatment which might not be possible otherwise.
However, several studies stated that high readmission rates,
more particularly within 30 days of discharge, can be quite
disruptive to patients and their families and costly [16] [17].
To our knowledge, few UK studies attempted to identify predictors of (re-)admissions to psychiatric units (or
hospitals) as the major challenge is the availability and
accessibility of relevant data. In 2008, the Information
Services Division Scotland developed a risk predictive tool
similar to SPARRA to identify individuals at risk of readmission to psychiatric units, namely SPARRA Mental Disorder
(Scottish Patients at Risk of Readmission and Admission (to
psychiatric hospitals or units) [18].
IV. C ORRELATED VARIABLES
Table I presents correlated variables to admission risk
based on selected studies.
V. R ISK S CORING I NDICES
A. Comorbidities
Adjustment for comorbidity is common in clinical outcome risk adjustment. Two most common measures [19]
are Charlson Comorbidity Index (CCI) [20] and Elixhauser
Comorbidity Index (ECI) [21], which are used for predicting
admission and mortality. There have been revised versions
of CCI and ECI, including the most recent CCI updates by
Table I
C ORRELATED VARIABLES
Category
Case mix group of diagnoses
Case mix group of operations
Insurance & medical claims
Demographics
Deprivations
Times, types, consultations, sources, waiting &
length-of-stays for admissions or discharges
Geographical location of patient & care provider
Physical condition
Social care status
Psychological health, emotional state & social
functioning
Clinical indicators, treatments, medications &
compliance
Risk indices
Examples
Patterns of Morbidity with Adjusted Clinical Groups, chronic condition with Expanded Diagnosis
Clusters, diagnosis categorisation, ACS, frequent comorbidities & chronic conditions.
National Clinical Coding Standards (OPCS) classification, & Agency for Healthcare Research and
Quality (AHRQ) procedure categorisation.
Grouping clinically similar treatments with Healthcare Resource Groups (HRGs).
Age, race, gender, & marital.
Index of Multiple Deprivation (IMD), which includes: income, employment, health & disability,
education, skills & training, barriers to housing & services, living environment, & crime.
Using clinically homogeneous units that describe complete episodes of care using Optum Episode
Treatment Groups, the number of emergency admissions in different timeframes, & types and the
number of specialities.
Type & location of hospital & population estimates of local authorities.
Functional physical activities, & general health.
Skilled nursing facility, rehab, hospice & palliative care.
Social isolation, loneliness, physical activities, life satisfaction, anxiety & depression, quality of
life, & general mental health.
Lab test results, & prescribed medications.
A version of Charlson comorbidity index & Elixhauser comorbidity index.
Dr. Foster [22] and bottle et al. [23], and AHRQ adaptation
of ECI [24].
Moreover, ACS conditions [9] are seen as potentially
avoidable, and are highly correlated to multiple admissions
over time and quality of care [25]. Also, there have been
other attempts to cluster conditions based on factors, like
length-of-stay and severity, such as John Hopkin’s Aggregated Diagnosis Groups and Selection of Multipurpose Australian Comorbidity Scoring System [26]. Moreover, another
approach to comorbidity scoring is using a cost function, like
UK’s HRG [27], and the Centre for Medicare and Medicaid
Services Hierarchical Condition Category (CMS-HCC) [28].
However, use of comorbidity scoring in predictive models
is sometimes criticised. Criticisms stem from using unrepresentative timeframes and population, coding inaccuracy of
diagnoses, the inconsistency of cost functions, implementing
additive risk model and not adjusting for important factors,
such as age, gender, deprivations and length-of-stay.
B. Operations and Procedures
Moreover, there is an increasing evidence that quantification of high-risk operations and procedures with adequate
adjustment can greatly improve mortality and readmission
models [29]–[31]. But, unlike comorbidity, there is no
generic risk model for operations and procedures, and the
categorisations are mainly done based on clinical groups.
In the UK, NHS uses OPCS [32], and AHRQ’s procedure
categorisation scheme is used in the USA [33].
Nonetheless, there have been attempts to define a scoring
mechanism for patients with specific conditions, such as
the Royal College of Surgeons Charlson Score [34], EuroSCORE [35] and the model developed by Aktuerk et al.
[36] using HES.
In addition, there are a number of cost grouping models
besides HRG and CMS-HCC, which are more detailed, like
Bupa Operative Severity Score [37] and Surgical Outcome
Risk Tool [38].
C. Frailty
Frailty is one of the main problematic expression of
elderly and it develops as a consequence of ageing. The
time that is spent in poor general health, a limiting chronic
health or disability, can be attributed to frailty in some cases.
Frailty can be defined as a state of high vulnerability and the
decreased ability to sustain homeostasis, which is correlated
with high risk of adverse outcome including falls, delirium,
immobility and disability, incontinence and susceptibility to
medications side effect [39].
Frailty considerably changes care utilisation pattern due to
a significant increase in risks of comorbidity [40]–[42] and
adverse outcomes, such as fall, post-operative complications,
disability, mortality, prolonged length-of-stay, readmission
and institutionalisation. Therefore, there is a considerable
benefit in identifying these patients and proactively planning their care to enable rapid control of symptoms and
prioritisation of anticipated needs.
There are three major instruments in modelling frailty:
frailty phenotype model introduced by Fried et al. [40] (5
parameters), Canadian Study of Health and Ageing Frailty
Index (FI) by Rockwood et al. [43] (92 parameters) and the
Yorkshire and Humber Academic Health Science Network’s
electronic Frailty Index (eFI) [44] (36 parameters). The eFI
was developed in the UK using GP data, and currently
available via SystemOne primary care software in some
areas.
Also, it has been shown that more manageable 30 parameters of FI model [45], simpler models with minimal overlap
in identification [46] or existing electronic health record data
can have competitive predictive validity [44].
D. Social Isolation
Socially isolated individuals are typically two to five
times more likely to die prematurely. Social isolation is an
objective measure of the number of interactions a person has
in social life, and it is closely related to loneliness, which
is more subjective.
Social isolation and loneliness have no age boundary; but,
it is more likely to appear in older age, such as bereavement,
illness, physical or mental disability [47]. Also, findings
from the English Longitudinal Study of Ageing [48] shows
that disadvantaged socioeconomic groups are less likely to
participate in social activities and volunteering.
In the UK, the DoH has developed at set of 39 indicators
[49] to address both short and long-term health inequalities.
In addition, the Quality and Outcomes Framework came into
place to address the health inequalities needs in primary
care, and were defined based on the prevalence of disease
and deprivations. Also, the introduction of Health Impact
Assessments [50] process allowed local authorities to assess
the health effects of all relevant council policies, decisions
and investments.
Moreover, varieties of measurement tools were developed
to assess social integration, social networks and social
support. The assessment tools may be categorised into
four main criteria: social relations, social support, negative
relationships and loneliness [51].
Firstly, social relation measures, such as Social Network
Index, Social Relationships and Activity and Social Contacts
and Resources, mainly assess social ties and social integration.
Secondly, the social network category formally assesses
aspects of social network structures and are mainly used in
epidemiology, psychology and most recently in healthcare.
Two examples of social network measures are Egocentric
Network Name generators and Qualitative Network Measures.
Thirdly, the social support measures usually assess several
types of supports including emotional, instrumental, financial and appraisal. It includes measures, such as Lubben
Social Network Scale [52], Multidimensional Scale of Perceived Social Support (MSPSS) [53], Social Support Questionnaire, Norbeck Social Support Questionnaire, Medical
Outcomes Study Social Support Survey and Duke Social
Support Index. Lubben and MSPSS have shown to be
relatively reliable and consistent.
Fourthly, there are types of social relationships that have
a negative influence on health, network structure and social
behaviours, such as childhood trauma stemming from abuse,
marital quality and regulation of contact with an infectious
disease. Examples of negative relationships measurements
are Positive and Negative Social Scale Exchanges, Inventory
of Negative Social Interactions and Social Undermining
Scale.
Finally, the measurements in the loneliness category assess loneliness in terms of quantity and quality of social life.
Most of the measurements are based on the Lubben version
of the UCLA Loneliness Scale [54] and includes feeling
isolated, being part of a group and having someone talk to.
E. Other Markers
Other special population markers can be used including
disability conditions, pregnancy states, other complications
and adverse outcome, diagnosis specific, other psychological
conditions and other care specific models. An example is
JBS3 [55], which is used for prevention of cardiovascular
disease. More details about common clinical scoring practices can be found online from the NHS England and Hippo
Education team [56].
VI. C ONCLUSION
In this rapid review, recent predictive modellings for
social care utilisation and admission and readmission to
general and psychiatric hospitals were highlighted. Major
risk factors and risk prediction approaches were discussed.
Then, risk scoring methods were briefly summarised, including comorbidities, operations, procedures, frailty and social
isolation.
ACKNOWLEDGEMENT
We thank Docobo for their financial support through an
Innovate UK Small Business Research Initiative grant.
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