PALLI study: a study protocol for development and validation of a tool for the identification of people with intellectual disabilities who are in need of palliative care

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PALLI study: identification of people with ID who are in need of palliative care
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PALLI study: a study protocol for development and validation of a tool for the identification of
people with intellectual disabilities who are in need of palliative care
Milou G.M. Christians1; Cis Vrijmoeth1,2; Michael A. Echteld, PhD3,4; Marijke Tonino, MD PhD3;
Dederieke A.M Festen MD PhD2; Henny M. van Schrojenstein Lantman-de Valk, MD PhD1; Marieke
M. Groot, PhD5
1 Intellectual Disabilities and Health, Department of Primary and Community Health Care, Radboud University
Medical Centre Nijmegen, the Netherlands.
2 Intellectual Disability Medicine, Department of General Practice, Erasmus University Medical Centre
Rotterdam, the Netherlands.
3 Prisma Foundation Biezenmortel, the Netherlands.
4 Science in Balance Foundation Rotterdam, the Netherlands.
5Anaesthesiology, Pain and Palliative Medicine, Radboud University Medical Centre Nijmegen, the Netherlands.
Correspondence to
- Cis Vrijmoeth, Radboud University Medical Center, PO box 9101 (route 68), 6500 HB Nijmegen,
the Netherlands; cis.vrijmoeth@radboudumc.nl; tel +31 24 36 19 079.
- Marieke Groot, Radboud University Medical Center, PO box 9101 (route 549), 6500 HB Nijmegen,
the Netherlands; marieke.groot@radboudumc.nl; tel +31 24 36 66 252.

PALLI study: identification of people with ID who are in need of palliative care
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Abstract
Background:
Early identification of the need for palliative care is crucial, to prevent problems and relieve suffering.
Professionals who care for people with intellectual disabilities (ID) experience barriers in the
identification of those in need of palliative care, mostly due to communication challenges. The aims of
the PALLI study are 1) to develop a tool that will help healthcare professionals identify people with
ID who are in need of palliative care, and 2) to examine the validity and applicability of the tool.
Methods:
A mixed method design is used to develop the tool. First, ID-physicians and general practitioners
(GPs) complete a retrospective questionnaire about the process of palliative care provided to their last
patient with ID with a non-sudden death. In addition, interviews with physicians and professional
caregivers of people with ID regarding recognition of the need for palliative care are conducted. The
survey and interviews generate items relevant for identification. These items are subsequently
discussed and prioritized in focus groups.
The resulting preliminary identification tool is tested for validity and applicability in a
prospective follow-up study. 100 adult patients with ID receiving care from GPs and 100 adult patients
with ID receiving care from ID-physicians are included. Patients are followed during a 10-month
period, with data collection at 0, 5 and 10 months. Data include information on burden of illness,
symptoms, activities of daily living, and mobility. For those patients who die during the period of data
collection, information about the quality of death and dying is collected.
Conclusion:
This in-depth study ends up in a validated screening tool that will help healthcare professionals to
identify people with ID who are in need of palliative care. The tool is likely to contribute to timely and
patient-centered provision of palliative care.
Keywords: early identification, intellectual disabilities, end-of-life, palliative care

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Background
There is a growing awareness that early identification of the need for palliative care is crucial for
symptom relief and the prevention of problems in patients in the palliative care phase. Negative
consequences for those in need of palliative care, but not identified in a timely fashion, are untreated
pain and other symptoms, emergency admissions, unaddressed advance care planning, and an absence
of an individualized, well-considered plan of action [1-4]. Early identification enables all persons
involved to discuss patient’s values, preferences and care goals early in the course of an illness and to
make better informed decisions about the planning and provision of palliative care [5-7].
Despite the importance of early identification, little is known about this topic in people with
intellectual disabilities (ID; see box 1). Due to related challenges, such as difficulties and delays in
diagnosis, referral or treatment [8] and patient-professional communicational challenges [9], early
identification of people with ID who are in need of palliative care may be complex. People with ID
may not communicate symptoms or care needs, or communicate these in a different way [10, 11]. For
example, physical problems can manifest themselves as changes in characteristic behavior. Because of
these nonspecific expressions, signs indicating a need for palliative care can easily be missed or
misinterpreted and healthcare professionals have to work with assumptions, rather than clear
diagnoses.
The lack of research data and these challenges emphasize the need for support in identifying
the need for palliative care in people with ID. Several tools to support professionals identifying the
need for palliative care have been developed and tested in the general population [12], such as the
Radboud Indicators for Palliative Care Needs [13] or the Supportive and Palliative Care Indicators
Tool [14, 15]. As far as we are aware, these tools are not tested in the ID population and tools specific
for the ID population are not yet developed. The existing tools are unlikely to be applicable in the ID
population due to the above mentioned population characteristics.
In order to address this knowledge gap, we initiated the PALLI study: PALliative care:
Learning to Identify in people with intellectual disabilities. The aims of the PALLI study are 1) to
develop a tool that will help healthcare professionals identify people with ID who are in need of
palliative care, and 2) to examine the validity and applicability of the tool. In this paper we present the
PALLI study design and methodological approach.
Box 1. People with intellectual disabilities
“People with intellectual disabilities (ID) have significant limitations in both intellectual functioning and in
adaptive behavior, which covers many everyday social and practical skills. This disability originates before the
age of 18. Intellectual functioning - also called intelligence - refers to general mental capacity, such as learning,
reasoning, problem solving, and so on. Adaptive behavior is the collection of conceptional, social, and practical
skills that are learned and performed by people in their everyday lives.” (AAIDD; American Association on
Intellectual and Developmental Disabilities [16])

PALLI study: identification of people with ID who are in need of palliative care
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Methods
The development of the tool consists of two parts. First, the tool is constructed and then it is tested for
validity and applicability.
Part 1: construction of the tool
We use a four step procedure to construct the PALLI-tool.
Step 1: Retrospective survey
We ask ID-physicians (see Box 2) and GPs to complete a retrospective survey. This survey is based on
a survey used by Claessen et al. [17] in a nation-wide study among Dutch GPs about their last patient
with ID who did not die suddenly. The survey includes questions regarding immediate and underlying
causes of death; moment of recognition of patient’s death in the foreseeable future; signals that led to
this recognition, presence of symptoms on the moment of recognition; moment of discussion of the
start of the palliative care phase and its implications for care; treatment aims and interventions after
the moment of recognition; and barriers and facilitators of identifying the need for palliative care in
patients. We add questions considered relevant for people with ID and we modify some existing
questions to make them more suitable. The survey is pilot-tested among ID-physicians and GPs for
applicability, relevance and consistency.
ID-physicians are recruited via the Netherlands´ Society of Physicians for People with
Intellectual Disabilities (NVAVG) [18] and GPs via the primary care network around Radboudumc
Nijmegen, the Netherlands, and via the authors’ network. Permission to use the mailing list is obtained
from the chair of the network. Physicians are provided with information about the study and receive a
request for participation by email. Participating physicians are asked if they had provided palliative
care for a patient with ID. If they answer negative, we ask them to only complete questions on
physician characteristics, such as type of physician, gender, age, years of experience as physician, and
training in palliative care. Physicians who have provided palliative care for a patient are requested to
complete the entire survey.
Step 2: Telephone interviews
We then interview a purposive selection of ID-physicians and GPs who completed the retrospective
survey. Ten ID-physicians and ten GPs are selected in such a way that balanced distributions of
physicians’ work-experience and patients’ cause of death (cancer vs. non-cancer) and levels of ID are
obtained. In addition, we perform interviews with a convenience sample of 15 professional caregivers
of people with ID (see Box 2). The interview comprises questions regarding experiences with the
process of identifying the need for palliative care and related signals. Professional caregivers are

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recruited via the authors’ network and via an online announcement on the website of Agora, a Dutch
centre for support and information on palliative care [19].
Step 3: Focus groups
We extract signals related to the need for palliative care and barriers and facilitators of identifying the
need for palliative care from the data collected in step 1 and step 2. Based on these items a preliminary
tool is built which is discussed and prioritized in focus groups. We organize five meetings with
different professionals involved in the palliative care process: two with professional caregivers from
two different care organizations for people with ID, one with ID-physicians, one with GPs and one
with palliative care nurses specialized in care of patients with ID. In each group, six to ten participants
are recruited via the authors’ network and via an online announcement on the website of Agora.
Step 4: Development of the tool
After the preliminary tool is discussed in the focus groups, we modify the tool based on the
participants’ comments and supplements. This version of the tool is tested for validity and applicability
in part 2 of the study.
Box 2. Care of people with ID in the Netherlands
In the Netherlands, approximately 230 organizations provide care to a broad spectrum of people with ID [20],
varying in level of ID, mobility and co morbid conditions (e.g. visual, auditory or behavioral problems). The
organizations include different care settings: central residential settings, community-based homes, supported
living and day activity centers. In the central residential settings people with ID live together in homes on a
campus. Professional caregivers (social workers and nurses) deliver care on a daily (24-hours) basis. A general
practitioner (GP) or an ID-physician is the principal physician and responsible for the medical care. Since
February 2000, the medical specialism Intellectual Disability Medicine has been acknowledged in the
Netherlands. Physicians who completed the 3-year educational training are registered as Physicians for People
with Intellectual Disabilities (ID-physicians). For some patients the GP is the principal physician and the ID-
physician provides only care on GPs request or care for specific disability-related problems (e.g., behavioral
problems or epilepsy). Since the 1990s, the Dutch Government’s policy is to stimulate people with ID to move
from residential settings (‘institutions’) to supported accommodation in the community. These accommodations
include community-based homes and homes where people live independently. The amount of care provided
varies from a small number of hours a week to 24-hours a day. For medical care these people primarily rely on a
GP.

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Part 2: study of the validity and applicability of the PALLI-tool
The validity and applicability of the PALLI-tool is examined in a prospective follow-up study.
Study population and setting
Participants are 100 patients for whom a GP is the principal physician and 100 patients for whom an
ID-physician is the principal physician. Inclusion criteria are: people with ID (borderline to profound
ID, IQ < 85); aged 18 years or older; and a negative response on the surprise question of the Gold
Standards Framework [21]: “Would I be surprised if this patient died in the next year?” either by the
ID-physician or the team of professional caregivers. Patients who do not meet the criteria are
excluded. Participants are recruited from organizations that provide care to people with ID in the
Netherlands (see Box 2).
Instruments for outcome variables
In addition to the tool we develop, instruments used in the prospective follow-up study are selected on:
applicability in people with ID, applicability in palliative care populations, and psychometric
properties, if information is available.
Illness burden
To examine the patients’ illness burden physicians complete the Cumulative Illness Rating Scale
(CIRS) [22, 23]. The CIRS consists of thirteen items in seven body systems categories:
cardiac/vascular/respiratory; eyes-ears-nose-throat; gastrointestinal; urogenital;
musculoskeletal/integuments; neurological/psychiatric; endocrine/metabolic. For each item physicians
rate the illness burden on a 5-point Likert scale, i.e./ranging from no problem (0) to extremely severe
problem (4). The CIRS has been used in other palliative care populations [24, 25] and has proven to be
reliable and valid in a family practice context [26], but was not previously used in patients with ID.
Activities of daily living (ADL)
To examine the patients’ ADL-dependency, professional caregivers complete a Dutch translation of the
Barthel-Index (BI) [27]. The BI consists of ten items: bowels, bladder, toilet use, bathing, grooming,
dressing, feeding, transfers (bed to chair and back), mobility on level surfaces, and mobility on stairs.
For each activity professional caregivers rate the dependency on a two, three or four point scale; the
total ADL score ranges from 0 (completely dependent) to 20 (completely independent). The BI has
been used in people with intellectual disabilities with good results [28, 29]. The BI also has proven to
be a useful tool in people with life threatening illnesses [30].

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Symptoms
To examine the patients’ symptoms, professional caregivers complete the Utrecht Symptom Diary
(USD) [31], a modified and extended Dutch version of the Edmonton Symptom Assessment System
(ESAS) [32]. The USD consists of pain, sleeping problems, dry mouth, dysphagia, appetite,
defecation, nausea, shortness of breath, tiredness, confusion, anxiety, depression and wellbeing. For
each symptom professional caregivers rate the symptom burden at the moment using an 11-point
numeric rating scale, ranging from 0 (no symptom burden) to 10 (highest symptom burden). The USD
is part of a program to stimulate palliative care, funded by the Dutch government, and is therefore
widely used in palliative care settings in the Netherlands [33]. In addition to the USD items, we add
the degree to which patients suffer at the moment from fever, drowsiness, restlessness, seizures, and
the degree to which patients had shown weight loss or an overall decline in health in the past months.
Furthermore, we add questions from the Brief Hospice Inventory (BHI) [34] regarding the degree to
which symptoms were controlled, the degree to which patients were comfortable in the past days, and
the degree of patient’s quality of life at the moment.
Mobility
To examine the patients’ mobility, professional caregivers complete five questions regarding the ability
to walk in different settings based on the Hauser Ambulation Index (HAI) [35] and characteristics of
the Gross Motor Function Classification System (GMFCS) [36]. The settings include: at home,
work/school, less than 50 m in a safe environment, over 50 m in a safe environment, outside the safe
environment. For each setting professional caregivers rate the mobility on an eight point scale: (1) no
help, (2) using furniture or railing, (3) using cane or crutch, (4) using walker, (5) using wheelchair, but
able to move using his/her feet, (6) using wheelchair, but able to move using his/her arms, (7) pushed
in a wheelchair, (8) using electric wheelchair, (9) bedridden. The total mobility score ranges between 0
(walking independent in each setting) and 40 (bedridden). This assessment of mobility is previously
used in studies with people with ID [37, 38].
Quality of death and dying
To explore the patient’s quality of death and dying we interview the professional caregiver using the
format of the Dutch version of the Quality of Death and Dying (QODD) [39, 40]. This version of the
QODD consists of 17 items that contribute to the persons’ quality of end-of-life: pain under control,
control of event, control of bladder and bowels, breathing comfort; at peace with dying, unafraid of
dying, ability to laugh and smile, untroubled about strain on loved ones, maintained dignity and self-
respect, time with family/friends\other residents, physical expressions of affection, health care costs
covered, say goodbye, visit of religious or spiritual advisor, means to hasten death, dialysis or artificial
ventilation, and funeral arrangements in order. For each question the professional caregiver rates the
occurrence on a six point scale (never to always) or yes/no for the last seven questions, and then

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evaluates the occurrence on 11-point numeric rating scale, ranging from 0 (terrible experience) to 10
(almost perfect experience). The QODD has been used in other palliative care populations [40], but
was not previously used in patients with ID. We adjust the QODD to make it more suitable for use in
the care of people with ID.
Patients’ perception of their own quality of life and health
To explore the patients’ subjective quality of life we interview eligible patients using the format of the
Schedule for the Evaluation of Individual Quality of Life (SEIQoL-DW) [41]. The SEIQoL-DW is
administered by means of a semi-structured interview. Adjustments are made to make the SEIQoL-
DW suitable for use in people with ID. First, the patients name three to five areas that they find
important for their quality of life. Each area is reflected in a related visual cue, a pictograph, presented
by the researcher. This pictograph is used during the rest of the interview when the area referred to is
discussed. Second, patients determine the level of satisfaction or functioning in each area, using a
visual traffic light (green = as good as possible and red = as bad as possible) or using a visual scale of
five images of faces (very happy face = as good as possible to very sad face = as bad as possible).
Third, the interviewer asks the patient to rank the areas in importance, after which weight points are
assigned to the areas based on the ranking order. The SEIQoL-DW has been used in other palliative
care populations [42, 43], but not previously used in patients with ID.
In addition to the SEIQoL-DW, we use a semi-structured interview to ask patients questions
regarding their perception of their own health. First, we ask patients how healthy they think they are
using the visual traffic light or the visual scale of five faces. Second, patients are asked if they suffer
from any symptom or pain. In case of somatic symptoms, we ask patients to show where it is located
in their body using the picture of a person from the ESAS [32]. Third, we ask patients what they would
change of their body if they had the ability to change it.
The interview protocol and the visual aids are tested and discussed with a research assistant
with ID and adjustments are made based on her comments.
Procedures
An announcement of the study is published on the website of Agora and sent by email to GPs and care
organizations for people with ID in the authors’ network. Organizations are invited to participate in the
study. Interested care organizations are visited by the authors to present the study and provide
information on what participation entails. After informal agreement to participate, written formal
permission for the study to take place within the care organization is asked from the representative
advisory board and the board of directors. Then care organizations are visited by the authors to discuss
the procedure of informing all persons involved – i.e. local managers, professional caregivers,
physicians, patients and/or legal representatives – and of obtaining informed consent. This information
procedure differs for each care organization.

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Eligible patients are selected by ID-physicians or the team of professional caregivers. Before
the selection the physicians and professional caregivers receive information about the study, including
an explanation of the use of the surprise question. The aim is to include patients with different
characteristics, e.g. level of intellectual disability, medical history, and co morbid conditions. Selected
patients and/or their legal representatives receive information about the PALLI study via the care
organization.
Patients are included by the research team after written informed consent is obtained from the
patients themselves or the legal representative. We ask the principal physician or psychologist whether
patients are mentally competent to provide informed consent themselves. The patients receive
information, with adjusted texts and pictograms, for a better understanding.
Patients are followed over a ten-month-period. For each patient a physician (ID-physician or
GP) and a professional caregiver complete a coded online survey at baseline (T1), follow-up after five
months (T2) and follow-up after ten months (T3). The survey includes questions of the developed tool.
In addition, the survey for physicians includes questions about illness burden (CIRS) and for
professional caregivers question regarding activities of daily living (BI), symptoms (USD) and
mobility. A randomly selected subsample of fifty percent of the physicians and professional caregivers
complete questions with regard to applicability of the tool at T1; i.e. relevance of questions,
completeness of questions, comprehensibility of questions and duration of completing the tool. After
the study period the research team extracts data concerning medical consumption – contacts with
professionals, treatments, and use of medication – and co morbid conditions from the patients’ medical
files. If a patient dies during the study period, the research team contacts the professional caregiver to
offer condolences and to ask if they are willing to participate in a telephone interview in which
information about the quality of death and dying (QODD) of the patient is collected.
We conduct interviews with a selection of included patients with borderline to moderate
intellectual disabilities. In the first step of the selection, we ask the contact persons of each
organization (mostly physicians) to screen included patients for participation in an interview based on
two questions. First, “Is it advisable for the patient to participate?”. Related sub questions are:
“Whether or not is it advisable with regard to the patients’ health and the patients’ co morbid
conditions (e.g. visual, auditory and speech problems)”, “Would the patient be willing to
participate?” and “Would the patient enjoy participating in an interview?”. Second, “Is the patient
cognitively and physically able to understand the questions from the interview and answer them?”.
Related sub questions are: “Is the patient able to understand and answer simple and tangible
questions?”, “Is the patient able to reflect on and talk about his/her quality of life (what he/she likes
or dislikes, what he/she finds important)?”. In the case the contact person is not able to answer the
questions we ask the patients’ physician or professional caregiver. In the second step, we ask
professional caregivers of patients selected in the first step to answer the same two questions. After a
positive answer on both questions, we ask professional caregivers to approach the patient and his or

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her legal representative (if required). When a patient is willing to participate, informed consent (for
this part of the study) is obtained and the interview is planned. The interview takes place at a venue
preferred by the patient and, if desired, in the presence of a relative or professional caregiver.
Sample size
The sample size is based on the ability of the checklist to make an independent small distinction
between time points with respect to the different determinants (ADL, mobility, symptom, medical
consumption and illness change) scores. We used a linear multiple regression model to test whether
one variable (the checklist) can cause a small change (effect size=.2) controlling for four other factors
(yet to be determined). Power was set to .9, and the alpha error probability to .05. Using G*Power 3.1
[44], we determined the sample size to be 89. These analyses are planned in the GP and ID-physician
populations separately, making 2*89=178 respondents necessary. Taking possible patient drop-out
into account, we increased this number to 200.
Data analyses
The definition of the psychometric properties to be determined and their associated analyses are
derived from the Consensus‐based Standards for the selection of health Measurement Instruments
(COSMIN) [45]. In this study, content validity, construct validity, responsiveness and interpretability
of the checklist are tested. Content validity is studied by triangulating the views obtained from a
retrospective survey, the literature and experts. Construct validity is studied by examining associations
between the tool on the one hand and illness burden, ADL, mobility, symptoms, medical consumption
and co morbid conditions on the other hand. The independent association between the checklist and
these variables is assessed using multiple linear and logistic regression analysis. In addition, sensitivity
and specificity of the checklist in predicting survival is assessed; 95% confidence intervals are
provided. Responsiveness is assessed by associating baseline checklist data with follow-up ADL,
mobility, symptom, medical consumption and illness change scores, controlling for baseline outcome
data. Generalized linear models with random effects will be used for these analyses. Statistical
analyses will be performed using SPSS 21.
Ethics
The Ethical Review Committee of Radboudumc has concluded that the study does not fall within the
remit of the Dutch Act on Human Research and for this reason, full ethical review by a Dutch ethical
review committee was not necessary (reference number: 2014/074).
An advisory committee including ID-physicians and specialists in palliative care and/or people
with ID is related to the study and the research team. Patients, legal representatives and others
involved are offered the possibility to consult an ID-physician for independent judgment or advice.

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Discussion
Strengths
To the best our knowledge, the PALLI study is the first to address early identification of people with
ID who are in need of palliative care. The primary outcome is a practical screening tool that will help
healthcare professionals to identify these patients. We expect the tool to provide a starting point for all
persons involved, i.e. professionals, relatives and patients, to discuss a patient’s health status and his
need of palliative care in a multidisciplinary setting. Early identification with the tool is likely to
benefit the patient’s quality of life in the palliative care phase, because it enables to anticipate
problems and needs and to make end-of-life decisions in a timely fashion.
The combination of a retrospective and a prospective design allows to explore the process of
palliative care in depth and to provide secondary outcomes. With the retrospective survey and
interviews we gain insight into the barriers professionals face when shifting towards a palliative care
approach. The prospective follow-up study provides longitudinal data on changes in health, symptoms,
care dependence, medical consumption and quality of death and dying. Because we used online
questionnaires for physicians and professional caregivers, it is possible to follow a large cohort of
patients with ID for a significant period. A cohort study allows distinguishing palliative care
trajectories in people with ID, which will allow further progress in anticipatory care.
The study is not burdensome for the patient and does not interfere with the provided care. The
prospective study contributes to practice, by providing data for education of health care professionals
working with people with ID. Further research can enrich our data by including the perspective of
patients and relatives (parents, siblings).
Challenges
Because palliative care for people with ID is still a relatively small field of research, most instruments
that are well adapted for use in palliative care are not validated for use in this population. This
challenges us to critically monitor the use of the instruments throughout the study and to adjust the
contents when questions are not applicable to people with ID or when questions are in need of
modification. On the other hand, it also provides useful information about the applicability and
usefulness of the instruments.
In the development and validation of the screening tool, we are aware of the need to consider
the interpretation of the outcomes. It is possible that the results of the tool identify a patient as in need
of palliative care, when in fact another problem is the underlying cause. For example, problems
attributable to a reversible and treatable condition, serious life events (e.g. death or illness of a
relative) or significant changes in the proximal environment of the patient. We think the screening tool
can support in identifying those patients that may benefit from a palliative care approach, but careful
weighing of the outcomes by the treatment team involved is needed to decide on starting palliative
care and what the actual palliative care needs are.

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Conclusions
This in-depth study results in a valid screening tool that will help healthcare professionals to identify
people with ID who are in need of palliative care. In addition, we explore valuable data on the process
of providing palliative care and on patients’ health status during the palliative care phase. The
resulting tool is likely to contribute to timely provision of palliative care in line with the needs of the
patient.
Competing interests
The authors declare that they have no competing interests.
Authors’ contributions
MG, ME and HS initiated the study, drafted the design and applied for funding. MC and CV carried
out the study and drafted and revised the manuscript. MG and ME supervised and coordinated the
study. HS, DF and MT were members of the advisory committee. All authors are involved in revising
drafts and read and approved the final manuscript.
Acknowledgements
The Netherlands Organization for Health Research and Development (ZonMw) provided a grant for
this study (project number 1151.0033).
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