Walker et al. BMC Neurology          (2023) 23:373  BMC Neurology
https://doi.org/10.1186/s12883-023-03414-0
STUDY PROTOCOL Open Access
Transforming Parkinson’s Care in Africa 
(TraPCAf): protocol for a multimethodology National 
Institute for Health and Care Research Global Health 
Research Group project
R. Walker1,2, N. Fothergill‑Misbah2*, S. Kariuki3, O. Ojo4,5, R. Cilia6, M. C. J. Dekker7,8, O. Agabi4, A. Akpalu9, 
F. Amod10, M. Breckons2, M. Cham11, S. Del Din12,13, C. Dotchin1,2, S. Guggsa14, J. Kwasa15, D. Mushi16, 
F. O. Nwaokorie17, T. Park18, L. Rochester12,13, J. Rogathi7,8, F. S. Sarfo19, A. Shalash20, L. Ternent2, S. Urasa7,8 and 
N. Okubadejo4 
Abstract 
Background Parkinson’s disease (PD) is the second most common neurodegenerative disorder and, according 
to the Global Burden of Disease estimates in 2015, was the fastest growing neurological disorder globally with respect 
to associated prevalence, disability, and deaths. Information regarding the awareness, diagnosis, phenotypic charac‑
teristics, epidemiology, prevalence, risk factors, treatment, economic impact and lived experiences of people with PD 
from the African perspective is relatively sparse in contrast to the developed world, and much remains to be learned 
from, and about, the continent.
Methods Transforming Parkinson’s Care in Africa (TraPCAf ) is a multi‑faceted, mixed‑methods, multi‑national 
research grant. The study design includes multiple sub‑studies, combining observational (qualitative and quantitative) 
approaches for the epidemiological, clinical, risk factor and lived experience components, as appropriate, and inter‑
ventional methods (clinical trial component). The aim of TraPCAf is to describe and gain a better understanding 
of the current situation of PD in Africa. The countries included in this National Institute for Health and Care Research 
(NIHR) Global Health Research Group (Egypt, Ethiopia, Ghana, Kenya, Nigeria, South Africa and Tanzania) represent 
diverse African geographies and genetic profiles, with differing resources, healthcare systems, health and social 
protection schemes, and policies. The research team is composed of experts in the field with vast experience in PD, 
jointly led by a UK‑based and Africa‑based investigator.
Discussion Despite the increasing prevalence of PD globally, robust data on the disease from Africa are lacking. Exist‑
ing data point towards the poor awareness of PD and other neurological disorders on the continent and subsequent 
challenges with stigma, and limited access to affordable services and medication. This multi‑site study will be the first 
of its kind in Africa. The data collected across the proposed sub‑studies will provide novel and conclusive insights 
into the situation of PD. The selected country sites will allow for useful comparisons and make results relevant to other 
low‑ and middle‑income countries. This grant is timely, as global recognition of PD and the public health challenge 
*Correspondence:
N. Fothergill‑Misbah
tash.fothergill‑misbah@ncl.ac.uk
Full list of author information is available at the end of the article
© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which 
permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the 
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mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.
Walker et al. BMC Neurology          (2023) 23:373 Page 2 of 17
it poses builds. The work will contribute to broader initiatives, including the World Health Organization’s Intersectoral 
global action plan on epilepsy and other neurological disorders.
Trial registration https:// doi. org/ 10. 1186/I SRCT N7701 4546.
Keywords Parkinson’s disease, Africa, Diagnosis, Treatment, Epidemiology, Microbiome, Metabolome, Pesticides, 
Genetics, Prevalence
Background Health Organization (WHO) technical brief, +‘Parkin-
The population of Africa is growing and ageing faster son disease: a public health approach’, [16] alludes to the 
than any other region in the world [1]. The African pop- inconsistent data available on PD from low- and middle-
ulation aged 65 + is predicted to grow to 570 million income countries (LMICs), and the consequent difficulty 
by 2100 (for context, the population of all high-income of estimating the true burden in Africa or providing con-
nations of the world is projected to reach 387 million by vincing data to motivate governmental policy makers and 
2100) [1]. Sub-Saharan African countries will contribute donor agencies to prioritise PD on the continent. Better 
to over half of the global population increase through understanding of the prevalence of PD in communities 
2050. This population expansion and demographic shift would justify prioritising PD, inform national policies, 
is inadvertently accompanied by an increase in the bur- improve awareness of the disease, improve diagnostic 
den of non-communicable ageing-related neurological rates, and access to health services, and drive the focus 
diseases such as Parkinson’s disease (PD) and dementia on providing access to pharmacological and non-phar-
[2]. Yet ageing, ageing-related issues, and chronic con- macological treatments (e.g., physiotherapy). Until now, 
ditions associated with later life, are not adequately pri- there has only been one large scale prevalence study of 
oritised by most African countries. This is despite the PD in SSA, based on a house-to-house survey in Hai, 
abundance of evidence indicating the significant impact Tanzania, in which less than a quarter of people with PD 
(e.g., disability and dependency) attributable to such con- (PwP) had previously been diagnosed [17]. Furthermore, 
ditions, including neurodegenerative diseases [2, 3]. PD identifying the challenges and needs of PwP and their 
is the second most common neurodegenerative disorder families in different countries and contexts [7, 8] would 
and, according to the Global Burden of Disease estimates drive the narrative for local evidence-based policies [3].
in 2015, was the fastest growing neurological disorder Africa faces a stark gap in the provision of appropri-
globally with respect to the associated prevalence [4], ate neurological workforces and trained physicians [18], 
disability and deaths [5]. The high burden is fuelled by care, rehabilitation and treatment, making life for PwP 
increasing longevity, the effects of industrialisation and very difficult [19]. Awareness about PD is generally very 
environmental factors (for instance, pesticides, air pollu- low among the population [8, 20, 21] and healthcare 
tion and solvents), and genetic susceptibility [6]. professionals, resulting in under- and delayed diagno-
PD demonstrates significant heterogeneity in its cau- sis [10]. Exploring efficient and effective methods for 
sation (e.g., genetic, and environmental risk factors), diagnosing PD [22] (including use of telemedicine [23, 
access to specialised care and treatments and, inadvert- 24] and/or novel biomarkers) could facilitate diagnosis 
ently, quality of life and outcomes. Health disparities can at the primary care level, while offering opportunities 
affect patient outcomes negatively, and the social impact for early management [16]. Sustainable medication is 
may vary across cultures [7, 8]. Information regarding the largely inaccessible and unaffordable across the conti-
awareness, diagnosis, phenotypic characteristics, epide- nent [18, 25–28], however, investigations into alterna-
miology, prevalence, risk factors, treatment, economic tive sources of levodopa (e.g., Mucuna Pruriens (MP)) 
impact and lived experiences of people with PD from the have yielded positive results [29, 30].
African perspective is relatively sparse in contrast to the Exploring pathophysiological mechanisms and the 
developed world, and much remains to be learned from, genetic aetiology of PD has the potential to improve 
and about, the continent [7–12]. understanding of susceptibility, environmental clus-
There have been few PD prevalence studies (most tering and response to medication [9]. The develop-
from several decades ago) and no community-based ments in genome wide association studies (GWAS) have 
incidence studies in sub-Saharan Africa (SSA) [13–15]. largely excluded genetically diverse populations [31]. A 
Methodological flaws including the small population GWAS of PD among black Africans could provide a valu-
sizes surveyed and preponderant reliance on hospital- able source for finding novel genetic determinants that 
based data have given the erroneous impression that will inform new therapeutics that may eventually ben-
PD is rare in Africa. The recently published World efit patients from all populations [32, 33]. Mutations in 
W alker et al. BMC Neurology          (2023) 23:373 Page 3 of 17
genes commonly associated with PD, such as the Leucine 1. What is the prevalence of PD in Africa?
Rich Repeat Kinase 2 (LRRK2) gene have demonstrated 2. Are there unique risk factors (genetic and/or envi-
considerable regional variability, and have been virtu- ronmental) for PD in Africa and are there lessons 
ally absent in black Africans from sub-Saharan Africa in about PD in general that we can learn from the Afri-
studies reported to date [34–37]. This suggests the strong can perspective?
possibility that other yet undiscovered genetic factors 3. How can rates of PD diagnosis be improved?
may be at play. For example, the recently identified novel 4. Does the clinical phenotype of PD in Africa differ 
African-ancestry genetic risk factor in GBA1 [38]. Identi- from what has been reported in other populations?
fying environmental risks for PD is also crucial [39, 40], 5. How can the quality of PD management in Africa be 
and may identify a pathway to implement policy change improved?
to reduce exposure. PD is increasingly being referred 6. How can affordable and sustainable treatment for PD 
to as a ‘man-made’ disease [41], with pesticides [42, 43] be provided in Africa?
receiving substantial attention as an environmental risk 7. What is the current lived experience of people with 
factor for the development of PD. There is also strong PD, and their families, in Africa?
evidence for important metabolic interactions between 
the gut microbiome, the gut, the immune system, and the 
brain [44–48].
Considering the evidence presented, this study pro- Study setting
tocol outlines the United Kingdom (UK) National Insti- Seven countries are included in this NIHR GHRG (Egypt, 
tute for Health and Care Research (NIHR) Global Health Ethiopia, Ghana, Kenya, Nigeria, South Africa and Tan-
Research Group (GHRG) on Transforming Parkinson’s zania) (Fig.  1) representing diverse African geographies 
Care in Africa (TraPCAf) (Award No. NIHR133391). and genetic profiles, with differing resources, healthcare 
The NIHR is a major funder of high-quality global health systems, health and social protection schemes, and poli-
research that addresses the diverse health needs of peo- cies. This multi-country study will be carried out in two 
ple in LMICs and supports the objectives of the UK Aid research settings, namely within the community and in 
Strategy and the United Nation’s Sustainable Develop- hospitals (neurology clinics).
ment Goals (SDGs) 2015–2030. The overarching aim of All seven countries will be involved in outpatient 
this research grant is to transform the landscape of PD recruitment (see Table  1 for country sites). These 
diagnosis, treatment, and care across Africa. The pro- research sites were selected based on the track record 
tocol can also be accessed through the ISRCTN regis- of research active clinicians, with an interest in PD, able 
try (https:// doi. org/ 10. 1186/ ISRCT N7701 4546), where to identify eligible individuals attending outpatient clin-
updates on the progress of the study will be documented. ics. All hospitals included in the study are government, 
university-affiliated, or charitable organisations (not pri-
vate), capturing data from most of the population.
Methods The prevalence studies will be conducted in Tanzania, 
TraPCAf is a multi-faceted, mixed-methods, multi- Kenya, Nigeria, and Ghana (as described below), selected 
national research grant. We report the study methods based on the lack of epidemiological studies, the avail-
and design using an adaptation of the Standard Proto- ability of infrastructure and delineated populations for 
col Items: Recommendations for Interventional Trials a prevalence study (i.e., existence of a demographic sur-
(SPIRIT) guidelines [49, 50]. The study design includes veillance system or a known denominator population in 
multiple study aspects, combining observational (quali- representative rural/urban populations) and the facilities 
tative and quantitative) approaches for the epidemiologi- and staff with prior experience to undertake a house-to-
cal, clinical, risk factor and lived experience components, house survey.
as appropriate, and interventional methods (clinical trial 
component). A cross-sectional cohort design is employed 
for the observational components, while a double-blind 
randomised controlled trial design is used for the inter- Study design
ventional component. The study involves multiple study aspects (Table 2) that will be implemented across the seven countries (Table 1) 
in order to address the seven research questions above. In 
Aim and research questions all seven countries, participants will be recruited through 
The aim of TraPCAf is to describe and gain a better neurology outpatient clinics. In 4 countries (Ghana, 
understanding of the current situation of PD in Africa, Kenya, Nigeria, and Tanzania) participants will also be 
addressing the following seven key research questions: recruited through community-based prevalence studies.
Walker et al. BMC Neurology          (2023) 23:373 Page 4 of 17
Fig. 1 TraPCAf participating countries and sites marked with red box
Table 1 TraPCAf participating sites and outpatient locations Consenting participants can, but do not need to, participate 
Country Location Outpatient site in all study aspects. Furthermore, 2 healthy population con-
trols of the same ethnicity, matched for gender and age will 
Egypt Cairo Ain Shams University Hospital be recruited for every 1 PwP, providing the same biological 
Ethiopia Addis Ababa Tikur Anbessa Specialised Hospital and environmental samples as PwP (RQ2 and RQ3), and 
Ghana Accra Korle Bu Teaching Hospital undergoing the same clinical assessments (RQ4).
Kumasi Komfo Anokye Teaching Hospital The inclusion criteria for the prevalence studies are:
Sogakope Richard Novati Catholic Hospital
Kenya Nairobi Kenyatta National Hospital 1. Consenting resident in the delineated community 
Nigeria Lagos College of Medicine, University of Lagos for at least 12 months prior to the date of survey.
South Africa Durban Inkosi Albert Luthuli Central Hospital 2. Age 18 years or older for Tanzania, Kenya, Ghana 
Tanzania Moshi Kilimanjaro Christian Medical Centre (no upper limit) and > 40 for urban Lagos site.
Dar es Salaam Muhimbili Mloganzila Hospital
Inclusion criteria for PwP in all studies are:
Processes for recruitment 1. Consenting adults aged 18 years or older (no upper 
PwP identified through outpatient clinics, and through prev- limit) diagnosed with PD based on UK Parkinson’s 
alence studies, will be invited to participate in TraPCAf, will Disease Brain Bank (UKPDBB) clinical diagnostic 
be provided with information sheets on each of the different criteria [51] of any stage.
aspects of the research (see Table 2), and be able to consent 2. For the Mucuna Pruriens trial, PwP should be 
to particular study aspects. The clinical assessment (part of treatment naïve (summary of inclusion criteria 
RQ4) is the minimum involvement a participant can have. detailed in RQ6 section below).
W alker et al. BMC Neurology          (2023) 23:373 Page 5 of 17
Table 2 Overview of TraPCAf sub‑studies
Research question Outline of work Study component Study details
1. What is the prevalence of PD in Africa? Community, door‑to‑door prevalence studies Door‑to‑door household survey and clinical Community screening and clinical examination.
in 4 sites exam
2. Are there unique risk factors (genetic and/ Exploring the biological mechanisms of PD, a) DNA analysis Collection and analysis of blood and saliva 
or environmental) for PD in Africa and are there conducting genome‑wide association samples.
lessons about PD in general that we can learn and exploring the role of the microbiome b) Microbiome and metabolite analysis Collection and analysis of stool and buccal 
from the African perspective? and pesticide exposure in PD (cheek) samples.
c) Pesticide, heavy metal and trichloroethylene Collection and analysis of water, soil, and urine 
analysis samples.
3. How can rates of PD diagnosis be improved? Development and assessment of aids a) Biological diagnostic tools Collection and analysis of alpha synuclein 
to diagnosis, including use of screening tools, in blood plasma, blood serum and saliva samples.
technologies for gait assessments, and the role Collection and analysis of sebum samples.
of biological samples as possible diagnostic b) Technology diagnostic tools Collection and analysis of gait assessments.
tools Collection and analysis of neuromotor pen data.
Collection and analysis of Optical Computerised 
Tomography (OCT) data. Collection and analysis 
of smartphone application data.
4. Does the clinical phenotype of PD in Africa Phenotype PD using clinically validated scales a) Clinical assessment Clinical examination.
differ from what has been reported in other and understand progression of PD by follow‑ b) Technology for monitoring progression Collection and analysis of gait assessments.
populations? ing up PwP in outpatient settings Collection and analysis of smartphone applica‑
tion data.
5. How can the quality of PD management Understanding current management a) Economic evaluation Economic evaluation of current care and services.
in Africa be improved? and improving the management of PD b) Capacity building Understanding the role of video examination 
through training and telemedicine in PD care.
Training of healthcare professionals.
6. How can affordable and sustainable treat‑ Comparing Mucuna Pruriens versus levodopa/ Randomised controlled trial (RCT) Randomisation to MP or levodopa/carbidopa.
ment for PD be provided in Africa? carbidopa for the treatment of PD, includ‑ Economic evaluation.
ing an economic evaluation to assess cost‑
effectiveness
7. What is the current lived experience of people Exploring the lived experience of PD a) Qualitative interviews Analysis of interviews with PwP, family members 
with PD in Africa? through qualitative interviews, the develop‑ and stakeholders.
ment of information packages and educational b) Community education Development and evaluation of information 
campaigns, and the establishment of support packages.
groups Development and evaluation of educational 
campaigns.
c) Support groups Development and evaluation of support groups 
for PD.
Walker et al. BMC Neurology          (2023) 23:373 Page 6 of 17
Inclusion criteria for healthy controls are: specific and localised, taking into account national and 
1. Consenting healthy, neurologically normal regional considerations, while recognising similarities and 
(assessed at in-person physical examination) adults trends across communities and nations.
aged 18 years or older (no upper limit) who are age, 
gender and ethnicity matched (per country). Study components
Prospective participants will be excluded if they do not The following sections describe the details of the studies 
consent or lack capacity to consent (clinical judgment), outlined in Table 2, addressing research questions 1–7.
and/or are physically unable to complete study proce- All biological samples will be collected by a research 
dures due to advanced disease and physical disability. nurse at a clinic visit, unless otherwise indicated. All 
Participants will provide details of medical comorbidi- sites have a material transfer agreement with Newcastle 
ties, if known, during the clinical examination. University and collected samples will be shipped to New-
castle University for analysis in labs with relevant exper-
tise. Sites have the option to aliquot samples for analysis 
Group establishment in situ and for capacity building with expert support and 
Group establishment began before the awarding of the training.
grant, during the proposal development phase. This 
involved bringing together experts from across the seven RQ1. Prevalence studies in Ghana, Kenya, Nigeria, 
partner countries to develop the aims, research questions and Tanzania
and study methods of the grant. Importantly, this devel- To estimate prevalence of PD and/or parkinsonism in 
opment was guided by our community engagement and Ghana (South Tongu district, Volta region, population 
involvement (CEI) team. 113,114), Kenya (Kilifi, population 300,000), Nigeria 
CEI work ensured the research proposal was designed (Lagos, subset of population of 1.8 million), and Tanzania 
with, and for, people with PwP and their families. A (Hai region, population 180,000), door-to-door house-
2 hour virtual CEI meeting was held with 16 representa- hold screening will be carried out by local, trained health 
tives from Nigeria, Kenya, Ghana, and Ethiopia during workers in their designated areas/villages. Information 
proposal development to understand their needs, chal- recorded will include village name and precise geograph-
lenges and priorities, their interest and willingness to ical location, head of household, date of visit, name of 
participate, introduce the proposed research and solicit household member, age, and sex. The head of household 
feedback on the relevance, approach, applicability and will report on behalf of the household (if they are not 
objectives. For example, the research team highlighted present, anyone over the age of 18 will be able to respond 
the challenge of diagnosing people in a prevalence study on the household’s behalf ). Data on PD will be collected 
in contexts where there may not be access to affordable using an adapted screening tool (from methodology ini-
or sustainable drug treatment. However, PwP felt that tially described by Dotchin et al. (2008) in Tanzania [17]) 
knowing a diagnosis would give people a better chance to as follows:
manage the disease, avoiding perceptions associated with 
witchcraft. Considering this, we are confident that under- 1. Do you walk more slowly than other people your age?
standing the prevalence of PD across the sites is vital, 2. Do your arms or legs shake?
and knowing a diagnosis may outweigh the challenges of 3. Do you shuffle or take short steps when you walk?
medication accessibility. The CEI team also echoed the 4. Do you fall easily?
need for information about PD burden to push for local 5. Has anyone told you that you have Parkinson’s dis-
policy changes. ease?
Post-award, the group establishment phase has involved 
ethics application submissions, mapping research priori- Any positive responders will be reviewed by a study 
ties, acquiring necessary  consumables,  a review of exist- clinician in the community to determine likely diagno-
ing literature on PD from participating countries, and the sis and advised appropriately. If it is thought they might 
planning of CEI activities in-country. The role of CEI in have PD, they will be invited to an in-person physician 
this project is to improve the equality, efficacy and impact assessment and neurology examination to determine 
of responses and services by ensuring that PwP are active diagnosis. Those found not to have PD (or other neuro-
stakeholders in the deliberations, design, decision-mak- logical condition) will be provided with referral advice to 
ing, implementation, and dissemination of the project. an appropriate healthcare facility. Those diagnosed with 
This will be monitored using the Community Engage- a neurological condition will be registered at the local 
ment Process Index. Working with CEI representatives clinic for follow-up care. All individuals diagnosed with 
from each country ensures that our engagement is context 
 Walker et al. BMC Neurology          (2023) 23:373 Page 7 of 17
PD during the prevalence studies will be invited to par- genotyping platform). Genome-wide analysis data 
ticipate in further study aspects. comparing PD and controls will also be reported as 
The primary outcome measures for the prevalence an outcome by the TraPCAf research team in collab-
study will be the number of people with idiopathic PD oration with GP2.
per 100,000 of the population studied in each country 
[52], with age standardisation to the WHO population. b) Microbiome and metabolite analysis
We will also be reporting on the number of vascular par-  Stool samples and buccal swab samples will 
kinsonism cases per 100,000 population – in view of the be collected using standardised equipment across 
high rates of undiagnosed and untreated hypertension in all sites from all consenting participants for 16S 
SSA, we expect there may be high rates of vascular par- sequencing for microbiome analysis  and metabolite 
kinsonism. The secondary outcome measure will be sex- analysis [54]. All datasets obtained will be identified 
specific prevalence of PD in Africa (measured as number to bacterial species-level operational taxonomic units 
of male and female per 100,000 population), again with (OTUs) to differentiate the faecal community com-
age-standardisation. position of individuals from the rural and urban com-
munities under study. Analysis pipeline to capture 
RQ2. Risk factors for PD microbiota data on alpha diversity, beta diversity, dif-
ferential abundance of microbial taxa and functional 
a) DNA analysis gene will be utilised [54]. Primary outcome (con-
 TraPCAf recruitment will link with the Global ducted at baseline) will be the difference between 
Parkinson’s Genetic Program (GP2) (www. gp2. org) cases and controls. In conjunction with microbiome 
and the Aligning Science Across Parkinson’s (ASAP) and metabolite analysis, a questionnaire on diet and 
initiative (www.p arki nsons roadm ap.o rg). The ASAP medication use (see supplementary information) 
initiative is devoted to accelerating the pace of dis- developed for the purposes of addressing TraPCAf 
covery and informing the path to a cure for PD research questions will be administered. Samples will 
through collaboration, research-enabling resources, be linked to individuals’ genotypic and phenotypic 
and data sharing. GP2 is a resource programme of data to allow for further analysis.
the ASAP initiative focused on improving under-
standing of the genetic architecture of PD and mak- c) Pesticide, heavy metal and trichloroethylene 
ing this knowledge globally relevant. analysis
 To estimate the impact of environmental expo-
 In summary, genome-wide association stud- sures on the development of PD, water and soil sam-
ies and related genomics explorations will be con- ples will be collected using standardised procedures 
ducted utilising DNA extracted from whole blood from the homes of identified participants who con-
and/or saliva samples. The aim of this collaboration sent. This will primarily involve participants recruited 
is to contribute 1000 samples across TraPCAf sites through the prevalence study but those attending out-
(plus 2000 samples from healthy controls), which patient clinics will also be invited to participate in this 
will be shared with GP2 for analysis and sequencing, study aspect and given the equipment and instructions 
contributing to GP2’s goal to genotype more than to collect and bring samples from their homes to their 
150,000 unique samples from diverse populations. next clinic visit. Samples will be analysed for pesti-
cide content, heavy metal content and the presence of 
 We will work closely with our CEI team to deter- trichloroethylene. In conjunction with the analysis, the 
mine how best to return genetics results for variants mini-environmental risk factor questionnaire (MERQ-
whose significance is known (i.e., clinically relevant PD) [55] will be administered in a case–control design 
information) to PwP and understand what follow up and analysed alongside pesticide data from collected 
and counselling is available in-country. Where exper- samples. A pesticide and heavy metal exposure ques-
tise is lacking, we will work with GP2 to build capac- tionnaire, developed by the TraPCAf team for the pur-
ity in genetic counselling. Anonymised genotypic poses of addressing the research question (supplemen-
data will be linked with phenotypic data and microbi- tary material), will also be administered to understand 
ome analyses. The primary outcome will be the Odds historical toxin exposure.
ratio (or Hazards ratio) of specified single nucleotide  Urine samples will also be collected from con-
polymorphisms (SNPs) measured as the frequency of senting participants at the clinic visit and analysed 
polymorphic variation in PwP versus controls (based for pesticide residue levels to determine individual 
on the genotyping results from the NeuroChip® [53] exposure. Levels will be compared to previously 
Walker et al. BMC Neurology          (2023) 23:373 Page 8 of 17
published results indicating potentially dangerous  Metabolome analysis Metabolomics is the analy-
exposure. Inclusion of urine samples will provide sis of small molecule metabolites contained within cell, 
an indication of body burden but also of recent and tissue and biofluid systems. PwP may have a particular 
continued exposure levels. Environmental risk fac- odour, and this is currently being investigated at the 
tors for PD will be measured at baseline using (i) University of Manchester (www. mbc.m anche ster.a c. 
toxicology assessment for contaminants of emerg- uk/b arran group). We are collaborating with the team 
ing concern related to PD (including pesticides, leading this work to investigate whether metabolites 
herbicides, other chemicals) in the soil and water can be used to diagnose PD [22, 58] (covered by patent 
samples at residences of PwP versus healthy con- rights US20230077659A1 and US20230080918A1). 
trols and (ii) comparison of the risk exposures The team have developed a diagnostic platform, using 
of PwP and controls based on responses in the mass spectrometry, that can classify PD from sebum 
MERQ-PD questionnaires and reported as the rela- samples with up to 78–88% accuracy (for detailed 
tive risk of exposure for each subcategory of risk methodology see [22, 59]). Briefly, sebum samples 
factors interrogated. will be taken by a research nurse with a cotton bud 
rubbed on the upper back (a sebum-rich area of the 
RQ3. Aids to diagnosis for PD body) for metabolite analysis. Primary outcomes for 
We will explore the diagnostic utility (predictive values) this analysis (conducted at baseline) will be the diag-
of several innovative methods for improving the clini- nostic utility of skin metabolites measured in sebum in 
cal diagnosis of PD. These include the use of biological differentiating PwP from controls. Metabolome sam-
markers, as well as technological methods (see Table 2). ples will also be linked with phenotypic and genotypic 
Primary outcome measures for the sub-studies explor- data. It is important to determine whether the “PD 
ing aids to diagnosis will include the diagnostic utility, signature” identified is a pure disease-related signa-
positive predictive value, accuracy of diagnosis of PD ture and will be detected in Africans with PD, despite 
versus normal control, area under Receiver Operating genetic, epidemiological, and dietary differences. Find-
Characteristics (ROC) curve, negative predictive values, ings will confirm the more widespread utility of swabs 
sensitivity, and specificity of the diagnostic modalities as a methodology to help diagnose PD and provide 
described. For all study aspects within this RQ, consent- a unique window into underlying pathophysiology. 
ing participants will be invited to provide samples, or to This could be particularly useful in Africa, as samples 
trial the technology tools. remain stable at room temperature for several weeks, 
facilitating storage and transport.
a) Biological diagnostic tools
b) Technology diagnostic tools
 Plasma, serum, saliva, and urine analysis 
Aggregated alpha-synuclein in brain and periph-  Digital mobility outcomes Gait assessment can 
eral nervous system tissue is a diagnostic feature of discriminate and predict early disease, track disease 
PD. We are collaborating with a team at Newcas- progression, and identify therapeutic response in 
tle University, through registered partner company PD [60]. Wearable technology (such as accelerom-
‘ESP Diagnostics’ (www. espdia gnos tics. com) who eters and inertial measurements units (IMUs)) offer 
have developed an assay for extra-cellular synucle- a low-cost, unobtrusive solution to record the sig-
inopathic protein (ESP), that detects recombinant nals needed to extract comprehensive gait features 
alpha-synuclein aggregation using a fluorescent dye in laboratory and real-world scenarios. Widespread 
(covered by patent rights (WO2019/171035A10)). development and adoption of commercial sensors 
This works on urine, blood plasma and blood by the public for activity monitoring demonstrates 
serum samples, requiring equipment available in their feasibility and acceptability in HICs, but these 
most hospital biochemistry laboratories (for fur- technologies have been under-utilised in LMICs to 
ther information on the sensitivity and specificity date. Axivity AX6, a low-cost non-invasive wearable 
using saliva see [56, 57]). Blood will be taken using device (www.a xivit y.c om/p rodu ct/ ax6) which is a 
standard blood-taking equipment by a research data logger capable of recording raw data from a suite 
nurse. For saliva, the participant will spit into a of integrated sensors) [61, 62] will be used to objec-
tube. Urine will be collected in a plastic beaker. All tively monitor mobility (walking activity and gait) 
samples will then be prepared, aliquoted and stored during free-living mobility in PwP. This study aspect 
appropriately. will initially be rolled out to participants in Ghana, 
and potentially other sites based on initial outcomes. 
W alker et al. BMC Neurology          (2023) 23:373 Page 9 of 17
Briefly, the sensor is secured to the participant’s this work, we propose to build on advanced statis-
lower back (see [61] for image of placement) who tical models developed by our collaborators in the 
will be advised to continue with their usual activities ‘OCTAHEDRON’ project at Newcastle University 
and not change their routine, with monitoring over 7 (www. resear ch.n cl. ac. uk/o ctahe dron) to automati-
days [63]. The device quantifies digital mobility based cally identify biomarkers of PD diagnosis in retinal 
on walking speed, step count, walking bout number OCT scans [69]. Such tools have been developed 
and duration, for example. The device has previously using data mainly from the eyes of individuals in 
been validated in the UK [62, 64] and piloted in peo- white populations from high-income countries. We 
ple with frailty in Tanzania [61], demonstrating fea- aim to validate and tune these models to ensure they 
sibility. Based on previous estimates (pilot in Tanza- also serve the health needs of LMIC populations 
nia), we will initially recruit 50 PwP from the Ghana [70]. The increased accessibility of OCT imaging in 
sites. Gait assessments will also be used to monitor lower resource settings highlights the relevance for 
disease progression as part of RQ4. diagnostic and disease monitoring. In addition, data 
collected will allow the exploration of biomarkers for 
 NeuroMotor Pen (NMP) The NMP is a hand-held present and future disease progression to maxim-
medical device, developed by ‘Manus Neurodynam- ise the impact of limited clinical resources. All sites 
ica’ (www. manus neuro.c om), with a unique patented with this equipment available, and with the necessary 
system combining sensor technologies in a digital expertise to carry out retinal imaging, will be able to 
pen with software and an analytical engine with Deci- enrol participants to this study aspect.
sion Support System. The interface enables users to 
non-invasively record parameters of minute limb and  Oxford smartphone application The ‘Oxford 
hand motion from graphical tasks and apply auto- Parkinson’s Disease Centre’ in the UK (www.d pag. ox. 
mated analysis, with high reproducibility [65]. These ac.u k/o pdc) have piloted, tested and refined a 6-min 
parameters are used as ‘digital biomarkers’ to provide smartphone test of motor symptoms in 522 partici-
objective information about movement abnormali- pants with early PD, prodromal Rapid Eye Movement 
ties. The NMP, designed with a specific intended use (REM) sleep behaviour disorder (RBD) and age-
in the clinic, assesses and quantifies motor skills based matched controls, showing accuracies of 85–92% in 
on simple copying (writing and drawing) tasks that distinguishing PD versus control and RBD versus PD 
are not dependent on literacy. Unlike wearables, the [71]. Using novel machine learning algorithm MLA 
NMP measures subtle symptoms that cannot easily data approaches, they can use this smartphone test 
be seen or quantified with the naked eye and provides to predict motor Unified Parkinson’s Disease Rating 
a test of the extrapyramidal system. Symptoms cur- Scale (UPDRS) with a high level of accuracy, and to 
rently recorded with the UPDRS, such as bradykinesia predict clinically relevant change, such as the onset 
and tremor, can be objectively quantified with NMP. of falls, 18 months before occurrence, with positive 
Previous research suggests that the NMP is a quick, predictive values around 90% [72]. The applicability 
inexpensive, non-invasive and objective aid to diagno- of this smartphone application to the African con-
sis [66]. The NMP has undergone two phases of clini- text will be initially tested in 4 sites, and rolled out 
cal validation in European cohorts with high differ- to additional sites once usability is better understood. 
ential diagnostic sensitivity (PD vs not PD) (80%) and The app could be used to accurately distinguish PD 
high specificity (75%). This technology will be initially from controls (and PD from idiopathic REM sleep 
piloted with participants in 2 sites, and rolled out to behaviour disorder), providing a growing consensus 
additional sites after the feasibility of use in lower for the utility of digital biomarkers in early and pro-
resource settings is better understood. dromal PD, which could be of particular use in set-
tings where specialised clinicians are lacking. The 
 Optical coherence tomography (OCT) imag- smartphone application will also be used to monitor 
ing People with confirmed and prodromal PD have progression as part of RQ4
been reported to have changes in retinal structure 
[67]. Retinal imaging via OCT is a quick, non-con- RQ4. Clinical phenotype and progression of PD
tact, inexpensive method to detect these changes. 
It is an infra-red based imaging technology with no a) Clinical assessment
eye drops required, making it well tolerated. Yet, 
retinal changes have yet to be used to detect neu-  All PwP, either previously or newly diagnosed 
rological disease or monitor progression [68]. In from each site, will be invited to a detailed exami-
Walker et al. BMC Neurology          (2023) 23:373 Page 10 of 17
nation and assessment using standard disease spe- other movement disorders, primarily because much 
cific questionnaires, e.g., the International Parkin- of the physical exam findings are visual [24]. Tel-
son and Movement Disorders Society Unified PD emedicine can provide an accessible, cost-effective, 
Rating Scale (MDS-UPDRS) (see Table  3), in addi- and high-quality healthcare services [90], and pre-
tion to study-specific questionnaires developed by sents as a promising avenue for the effective mobi-
the research team (see supplementary material). lisation and utilisation of the few neurologists in 
At yearly intervals we will follow up these cohorts, Africa. Within TraPCAf, video consults will be used 
including monitoring for disease progression (MDS to aid (confirm) diagnosis and determine feasibility in 
UPDRS and Hoehn and Yahr scale) and cognitive all sites. This draws on technology developed and tri-
decline (using Intervention for Dementia in Elderly alled initially between Toronto and Lagos, and sub-
Africans (IDEA) and Montreal Cognitive Assessment sequently elsewhere, including Tanzania and Ghana 
(MoCA) scores), assessing response to treatment, as part of the African Section of the MDS. Scripted 
reviewing compliance with medication, and assess- videos are uploaded securely to the internet for 
ing motor symptoms (MDS-UPDRS total and Part III reporting by movement disorder specialists (see sup-
scores) and non-motor symptoms (MDS-NMS) [73]. plementary material). Video consults with scripted 
videos will be trialled across all sites and follow guid-
 A PD registry of participants at each site will ance detailed by Duker (2013) [91].
be established, with consent to contact and contact 
information (including phone numbers and next of  Training of healthcare professionals Research 
kin contact). Participants will be able to consent to and diagnostic capacity building have the potential to 
follow-up in the future, i.e., beyond the duration of empower African neuroscientists and allied health pro-
the grant. In line with this, we will be asking partici- fessionals (AHPs) with the means to develop innova-
pants to consent to being followed up and have their tive strategies that address local needs, transfer relevant 
contact details kept for 20 years after the study end technology, and provide solutions to decrease burden 
date, with the potential to follow up the cohort. and improve the quality of outcomes for PwP in Africa. 
Training and capacity building will increase the critical 
b) Technology for monitoring progression mass of African researchers with the ability to define 
research priorities, conduct epidemiological research, 
 The digital mobility outcomes and Oxford smart- conduct a diversity of economic impact evaluations, 
phone application described in ‘Technology diagnos- service delivery appraisals, and strategies for prevention. 
tic tools’ (RQ3) will also be used to monitor disease Clinical trials and development of non-pharmacological 
progression. evidence-based treatments remain a high priority. It is 
thus imperative to build a considerable pool of research-
RQ5. Improving PD management in Africa ers and clinicians/healthcare providers proficient in 
conducting research and providing diagnostic and thera-
a) Economic evaluation peutic services and with enough competency to partici-
pate meaningfully in collaborative international research, 
 An economic evaluation, involving a mapping who will be the future leaders that will sustain PD 
exercise of current care provision for PD as well as research, education and clinical competency in Africa.
modelling of alternatives to current care, will be car-  A survey of the 7 participating countries will 
ried out. This work will take the form of a cost conse- be conducted to identify training priorities among 
quence analysis of the diagnosis and management of healthcare professionals. Capacity building initiatives 
PD, including use of formal health services, alterna- will aim to train neurologists, geriatricians, nurses 
tive healing (e.g., visits to traditional healers), patient and AHPs in PD management as well as epidemiol-
related costs, days lost to care and the impact on eco- ogy, biostatistics, clinical trial methods, bioethics and 
nomic productivity. These data will be collected as grantsmanship. Ultimately, this will build multidisci-
part of the modified RUD questionnaire (Table 3). plinary models of care for PD, informing policy and 
practice which could be replicated for the manage-
ment of other chronic and age-related conditions, 
b) Capacity building while also building capacity for programme devel-
opment at a postgraduate level to ensure long-term 
 Video examination and telemedicine Telemedi- training and research is enabled. The team will build 
cine programmes are particularly suited to PD, and on past experience running such educational events 
W alker et al. BMC Neurology          (2023) 23:373 Page 11 of 17
Table 3 Data collection tools to be administered during clinical examination and assessment
Tools and questionnaires
Clinical  observationsa
Neurology  assessmenta
Questionnaire on women’s  symptomsa,b
Healthcare resource use  questionnairea,c
MDS Unified PD Rating Scale (MDS-UPDRS) [74]
Clinical impression of severity index (CISI-PD) [75]
MDS Non‑Motor Symptoms Scale (NMSS) [76]
Barthel index [77]
Intervention for Dementia in Elderly Africans (IDEA) cognitive screening tool [78]
Mini‑environmental risk factor questionnaire (MERQ-PD) [55]
Questionnaire on pesticide  exposurea
Questionnaire on  microbiomea
PD Questionnaire (PDQ-8) [79]
EuroQol‑ 5 Dimension instrument (EQ5D-5L) [80]
REM sleep behaviour disorder questionnaire (RBDSQ) [81]
Hospital Anxiety and Depression Scale (HADS) [82]
Montreal Cognitive Assessment (MoCA) [83]
PD Sleep Scale (PDSS) [84]
Epworth Sleepiness Scale (ESS) [85]
Questionnaire for impulsive‑compulsive disorders in PD – Rating Scale (QUIP-RS) [86]
Scales for outcomes in PD – Autonomic (SCOPA-AUT ) [87]
a Unvalidated questionnaires developed (based on expertise) for the purposes of addressing TraPCAf research questions (see supplementary material)
b Questionnaire developed and adapted from the Fox insight ‘Experience of women with PD’ survey [88]
c Questionnaire developed and adapted from the ‘Resource Utilization in Dementia’ (RUD) instrument [89]
in Africa (in-person and virtually). For example, the prepared to comply with the double-blind design, i.e., 
International Parkinson and Movement Disorders mock tablets and mock MP flavoured powder. The trial 
Society (MDS) ‘Overview of Movement Disorders will use methodology for the current multi-centre trial 
for Physicians, Nurses and Allied Health Profession- of MP in Ghana (trial registered on Cochrane Central 
als course’ held in Moshi, Tanzania in 2019, and the Register of Controlled Trials (www.t rial search.w ho.i nt/ 
‘MDS-Africa Nurse and Allied Health Professionals Trial2. aspx? Trial ID= PACTR 201611 0018 82367)), where 
Course for Parkinson’s Disease’ online course held in detailed methods can be found. Methods for the trial are 
2021. The team will also utilise the expertise of col- briefly outlined here:
laborating organisations, for example, GP2.
Inclusion criteria 
RQ6. Randomised clinical trial of mucuna pruriens  (i) age range 30 to 80 years.
Mucuna Pruriens (MP) is a levodopa-containing legu- ( ii) diagnosis of clinically probable or clinically estab-
minous plant that grows wild in tropical regions of the lished PD according to currently established crite-
world. Therefore, MP-based therapy has the potential ria [92].
to replace or supplement levodopa-based medicines in  (iii) newly diagnosed PD < 2 years.
countries where levodopa is unaffordable and inaccessi- ( iv) never treated with levodopa (drug-naïve) or treated 
ble due to the low costs of preparation of MP and high for only ≤ 6 months during the disease course but 
natural availability (up to 9.5% levodopa content) [29]. Levodopa discontinued since at least 3 months.
We will undertake a phase II, 12-month, 2-centre dou-
ble-blind (participant and investigators), parallel-group, 
randomised controlled trial (RCT), only in Tanzania, Exclusion criteria 
addressing the drug naïveiority of MP versus levodopa/
carbidopa (which is the reference treatment) for the (i) dementia according to DSM-V criteria precluding 
treatment of PD in drug-naïve PwP. Medication will be the subject to provide written informed consent.
Walker et al. BMC Neurology          (2023) 23:373 Page 12 of 17
(ii) clinically significant psychiatric illness (e.g., severe RQ7. Lived experience of PD
depression or psychosis).
(iii) Hoehn and Yahr stage 5/5 [93]. a) Qualitative study
(iv) severe, unstable medical conditions (e.g., neo-
plasms; unstable diabetes mellitus; heart, renal or  A qualitative study to understand lived experi-
liver failure). ences of PD will be conducted across all 7 African 
(v) pregnancy. sites. Semi-structured, audio-recorded interviews 
exploring diagnostic journeys, use of healthcare, 
Sample size The sample size [52] sufficient to have a care structures, experiences of stigma, among other 
power of 80% with a two-tailed type-I error of 20% to emerging aspects, will be carried out with PwP and 
detect clinically meaningful difference (effect size of primary caregivers. A purposive sample of 20 PwP 
0.5 according to Cohen [94]) is 74 patients (37 per each and 20 caregivers (with consent from PwP), totalling 
intervention). A drop-out rate of 20% was considered 360 participants, will be recruited from each site in 
for the final sample size calculation [95], resulting in 45 order to get a representative sample of, for example, 
patients per treatment arm. Randomised allocation will age, gender, disease stage, disease duration, socioeco-
be performed according to a computer-generated rand- nomic status. Furthermore, healthcare professionals 
omization list concealed by sealed envelopes. and policy makers will be invited to interview about 
their experience of PD (n = 20 per country). The pri-
Outcome measures The primary outcome is the non- mary outcome will be descriptions of lived experi-
inferiority of MP as measured by motor UPDRS subsec- ences of PwP across, and within, different sites. We 
tion score change over the time frame of the trial. The aim to understand what similarities populations 
main secondary outcome is the summary index of the experience with regards to PD, and where differences 
PDQ-8. Six assessments will take place at baseline, 1–3- exist to inform future interventions to support PwP 
6–9-12 months and at end of the study. The titration and caregivers in the community and inform policy 
phase is 4 weeks in which levodopa dose will be slowly to support their care.
titrated up to 4.5 mg/kg/day in three doses. Patients are 
randomised either to 40 weeks treatment with MP pow- b) Community education
der or to 40 weeks treatment with levodopa/carbidopa  Working closely with our CEI team, we will look 
tablets. An additional secondary outcome will be objec- at ways to increase awareness of PD in communi-
tive measuring motor performance using the Oxford ties, utilising local media outlets, training events, and 
smartphone app (detailed in 2.5.3). awareness-raising activities. The CEI team will lead 
on the development of culturally-specific informa-
Data handling With regards to data handling, and to tion packages for PwP and caregivers in local lan-
ensure privacy and confidentiality, all participants will be guages (where resources are not available already). 
pseudonymised. To minimise bias, only the lead inves- Ministries of Health will be involved from the outset 
tigator will be authorised to input patient data. Data is to maximise the potential for translating research 
password protected, for intended purposes only and will findings into practice. A needs assessment will guide 
be kept confidential and stored securely in a lockable the specific requirements of each site.
cabinet that can be assessed by the lead investigator.
c) Support groups
Trial economic evaluation An economic evaluation  Support groups play an important role in care 
will be conducted alongside the MP trial, comprised of and support for PwP and caregivers, while also filling 
a cost-utility analysis based on the incremental cost per in gaps in information and services that many health 
quality-adjusted life year (QALY) gained, based on the systems in low resource settings are unable to pro-
participants’ responses to the EQ5D-5L questionnaire vide [96]. Therefore, PD support groups are impor-
sand PDQ8. Intervention and follow up costs will also be tant components within these settings, ensuring PwP 
calculated from the perspective of formal health service and their families have the support they need, and a 
used and additional costs incurred by patients. We aim platform to advocate for PD. Support groups already 
to estimate the cost of the interventions, subsequent use exist in five of the seven countries we are working in. 
of services and additional costs to participants and their Support groups will be established in the two sites 
families to inform the cost-effectiveness and cost–benefit that do not already have groups (Egypt and Tanza-
of MP versus levodopa/carbidopa. nia). Additional groups, focussed on more rural areas 
of our seven countries, will also be established. A vir-
 Walker et al. BMC Neurology          (2023) 23:373 Page 13 of 17
tual support group, facilitated by our CEI partners, Ethical approval is already in place in Tanzania, Ghana 
Parkinson’s Africa, will also be made available to all and Nigeria at time of protocol publication, and will be in 
PwP and caregivers involved in TraPCAf. place in other sites before recruitment commences.
As stated in our ethical approval, all research partici-
Data analysis and management pants will be required to give fully informed, written 
A Research Electronic Data Capture (REDCap) database, consent to participate in any study aspect. All potential 
hosted at Newcastle University (UK), has been built and participants will be given an information sheet and will 
will be used to store all questionnaire data across sites. be able to read the information (translated in local lan-
Data will be analysed using standard statistical software guages as appropriate) or have it read to them. Partici-
packages (Statistical Package for Social Sciences (SPSS), pants will have the opportunity to ask questions about 
company of manufacture). Biological and environmental the project and can consent to the aspects of the study 
samples will be linked to questionnaire data on RED- they want to be involved with. Participants will not be 
Cap through associated barcodes (biobank) and samples taking part in any study aspect without knowing the 
stored at Newcastle University for analysis, or onward details of the study and their participation rights. Those 
transfer, as described. Technology data will be transferred who are unable to write (e.g., illiterate) will be able 
and uploaded to secure cloud servers and processed by to provide a thumb print on the consent form or have 
the technology owners (our collaborators). a witness append the form on their behalf, with verbal 
Data will be summarised using descriptive statistics consent. Participants will also be able to consent to fol-
appropriate to the nature of the data (e.g., mean, median, low up in the clinical aspect of the study. The only situ-
standard deviation, inter-quartile range, frequency). ation where participants may not be able to give full 
Bivariate inferential tests and multivariable modelling informed consent is if they lack capacity; this will be for 
will be used where appropriate. For the prevalence study, a very small group of individuals and is necessary for 
data will be presented as proportions of the denomina- the prevalence studies. In these cases, consent will be 
tor population, with sub-group analysis by sex and age obtained from their next of kin and we will gain their 
bands. Confidence interval generation will assume a verbal assent. Their further involvement in the study will 
bivariate distribution. For the RCT, independent sam- be minimal.
ple t-test will be applied, with either multilevel logistic Participants will receive a debriefing sheet after their 
regression or a mixed linear model during secondary participation in the study, which will provide a lay sum-
analysis to adjust for baseline score, treatment site, demo- mary of how the data collected will be stored and used 
graphic and disease factors not adjusted for by randomi- to transform the Parkinson’s landscape in Africa, as well 
sation. For screening tools, accuracy will be compared as reiterating their participation rights (e.g., right to with-
to the gold standard of expert physician opinion. The draw until data have been aggregated for analysis and 
primary measure of criterion validity will be area under reporting) and contact details for the study team. If they 
the receiver operating characteristic (AUROC) curve. consent, participants will also be linked with support 
Sensitivity, specificity, and predictive values will also be groups in-country and our charity partner network.
reported. Qualitative data will be managed using NVivo 
qualitative data analysis computer software and analysis Discussion
will be based on principles of Thematic Analysis [97]. Despite the increasing prevalence of PD globally, robust 
Data will initially be coded using a mixture of deduc- data on the disease from Africa are lacking. Existing 
tive and inductive coding after which coded data will be data point towards the poor awareness of PD and other 
analysed to identify key themes, which will emerge from neurological disorders on the continent and subsequent 
the data (not pre-identified). Throughout the lifecycle challenges with stigma, and limited access to affordable 
of the project, CEI advisory groups will feed back to the services and medication.
research team on data collection tools, recruitment and This multi-site study will be the first of its kind in 
be involved in preliminary analysis, as well as the devel- Africa. The research team is composed of experts in 
opment of appropriate methods for dissemination of the field with vast experience in PD (both clinical and 
findings to communities. research), jointly led by a UK-based and Africa-based 
investigator. We anticipate that the data collected across 
Ethics approvals and consent to participate the proposed studies will provide novel and conclusive 
Ethical approval for this study was granted by Faculty insights into the situation of PD on the continent through 
of Medical Sciences Research Ethics Committee, part of a deep understanding of those already accessing care 
Newcastle University’s Research Ethics Committee on and services, and persons with PD in the community 
1st February 2023 (Application No. 2453/26903/2021). who may have never obtained a diagnosis. The selected 
Walker et al. BMC Neurology          (2023) 23:373 Page 14 of 17
country sites will allow for useful comparisons and make LRRK2  Leucine Rich Repeat Kinase 2
results relevant to other LMICs. The grant will also pro- MDS  International Parkinson and Movement Disorders Society
MERQ‑PD:   Mini‑Environmental Risk factor Questionnaire‑Parkinson’s disease
vide opportunities for further studies driven by research- MJFF  Michael J Fox Foundation
ers in the TraPCAf sites and beyond and build a platform MoCA  Montreal Cognitive Assessment
for launching other collaborations including genomics NIH N ational Institutes for Health
NIHR  National Institute for Health and Care Research
and gene-environment studies and exploring the impact NMP N euroMotor Pen
of CEI activities and longitudinal studies on outcomes NMSS  Non‑Motor Symptoms Scale
(including patient-reported outcomes). OCT  Optical Coherence Tomography
OTU O perational Taxonomic Units
The limitations of the overall study mainly relate to the PD  Parkinson’s disease
scope of the work to be conducted within allocated budg- PDQ8  Parkinson’s Disease Questionnaire
ets. Efficient and effective communication across sites PDSS P D Sleep Scale
PwP P eople with Parkinson’s disease
and within the research team is crucial to ensure posi- QALY Q uality‑Adjusted Life Year
tive outcomes. Furthermore, feedback and input from the QUIP‑RS:  Q uestionnaire for Impulsive‑Compulsive disorders in PD Rating 
CEI team, as well as our External Advisory Group, and Scale
RBDSQ R apid eye movement sleep Behaviour Disorder Questionnaire
funders, will ensure the grant’s success. We are aware of RCT R andomised Controlled Trial
the issues relating to access to medicines, particularly for REDCap R esearch Electronic Data Capture
those who are diagnosed during the prevalence studies. SCOPA‑AUT:  S cales for Outcomes in PD Autonomic
SDGs  Sustainable Development Goals
Hence, the role of advocacy in tandem with the research SNP S ingle Nucleotide Polymorphism
is crucial to ensure that we build capacity and awareness SSA  Sub‑Saharan Africa
in each country. We are particularly keen to enable access SPIRIT  Standard Protocol Items: Recommendations for Interventional 
Trials
to affordable and sustainable medication and are working SPSS S tatistical Package for Social Sciences
with WHO and charitable foundations in respect to this. TraPCAf T ransforming Parkinson’s Care in Africa
Although the seven African countries broadly repre- UKPDBB U K Parkinson’s Disease Brain Bank
UPDRS U nified Parkinson’s Disease Rating Scale
sent different regions of the continent, we are necessar- WHO W orld Health Organization
ily limited to forging relationships and networks with 
active neurologists and researchers. Findings from this Supplementary Information
grant will enable us to replicate the work packages in The online version contains supplementary material available at https:// doi. 
other African countries, where even less is known about org/1 0.1 186/ s12883‑0 23‑ 03414‑0.
PD, through our capacity building initiatives. We hope 
to facilitate further training in countries where there are Additional file 1. 
few, or no, neurologists in collaboration with organisa- Additional file 2. 
tions such as the International Parkinson and Movement Additional file 3. 
Disorders Society (MDS), as well as grow patient net- Additional file 4. 
works in these countries. Additional file 5. 
This grant is timely, as global recognition of PD and Additional file 6. 
the public health challenge it poses builds. The work 
will contribute to broader initiatives, such as the WHO’s Acknowledgements
Intersectoral Global Action Plan on epilepsy and other The authors would like to thank the TraPCAf project management team 
neurological disorders [2] and align with the recom- at Newcastle University for their support. The authors would also like 
mendations outlined in the Parkinson Disease technical to thank the Editor for their helpful feedback and comments on the manuscript.
brief [16].
Authors’ contributions
NFM wrote the manuscript. RW and NO contributed to writing the manu‑
Abbreviations script and reviewed and approved the final manuscript. SK, OO, RC, MCJD, 
ASAP  Aligning Science Across Parkinson’s OA, AA, FA, MB, MC, SDD, CD, SG, JK, DM, FON, TP, LR, JR, FSS, AS, LT and SU 
AUROC A rea Under the Receiver Operating Characteristic all provided feedback on a draft manuscript and read and approved the 
CEI C ommunity Engagement and Involvement final manuscript.
CISI C linical Impression of Severity Index
ESP  Extra‑cellular Synucleinopathic Protein Funding
ESS  Epworth Sleepiness Scale This study is funded by the National Institute for Health and Care Research 
EQ5D 5L E uroQol 5 Dimensions (NIHR) in the UK (Award No. NIHR133391). The funding body provided peer 
GHRG G lobal Health Research Group review prior to awarding the research grant but did not play a role in the 
GP2 G lobal Parkinson’s Genetics Program design of the study, nor will they have a role in the proposed data collection, 
GWAS G enome‑Wide Association Study management, analysis or interpretation of data.
HADS  Hospital Anxiety and Depression Scale
IDEA  Intervention for Dementia in Elderly Africans Availability of data and materials
LMICs  Low‑ and Middle‑Income Countries Not applicable.
W alker et al. BMC Neurology          (2023) 23:373 Page 15 of 17
Declarations Received: 13 June 2023   Accepted: 29 September 2023
Ethics approval and consent to participate
Ethical approval to conduct this survey was obtained from Newcastle Univer‑
sity Faculty of Medical Sciences Ethics Committee in February 2023 (applica‑
tion number 2453/26903/2021). In‑country ethics approvals are either in place References
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