Research Article
Validation of Parkinson’s Disease-Related Questionnaires in
South Africa
Gill Nelson ,
1,2
Ntombizodwa Ndlovu ,
1
Nicola Christofides ,
1
Tintswalo M. Hlungwani ,
1
Irene Faust ,
3
and Brad A. Racette
1,3
1
School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 27 St Andrews Rd, Parktown, 2193,
South Africa
2
UCL Institute for Global Health, Research Department of Infection & Population Health, University College London,
London, UK
3
Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8111, St. Louis,
Missouri 63110, USA
Correspondence should be addressed to Gill Nelson; gill.nelson@wits.ac.za
Received 12 January 2020; Accepted 3 April 2020; Published 13 June 2020
Academic Editor: Graziella Madeo
Copyright©2020GillNelsonetal.isisanopenaccessarticledistributedundertheCreativeCommonsAttributionLicense,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background. ere are very few epidemiological studies investigating Parkinson’s disease (PD) in Africa. e hundreds of local
languagesanddialectsmaketraditionalscreeningandclinicalevaluationtoolsdifficulttouse. Objective.eobjectiveofthestudy
was to validate two commonly used PD questionnaires in an African population. Methods. e PD Screening Questionnaire
(PDSQ)andParkinson’sDiseaseQuestionnaire(PDQ-39)weremodifiedandtranslatedintoAfrikaans,Setswana,andisiZuluand
administered to a sample of healthy local residents. We assessed the internal consistencies and cluster characteristics of the
questionnaires, using a Cronbach’s alpha test and exploratory factor analysis. e questionnaires were then administered to a
population-basedsampleof416researchparticipants.Weevaluatedthecorrelationsbetweenthequestionnairesandbothatimed
motor task and the Unified Parkinson’s Disease Rating Scale motor subsection 3 (UPDRS3), using locally weighted scatterplot
smoothing(LOWESS)regressionanalysisandSpearman’srankcorrelation. Results.Bothquestionnaireshadhighoverallinternal
consistency(Cronbach’salpha=0.86and0.95,respectively).emodifiedPDQ-39hadevidenceoffivesubscales,withFactor1
explaining57%andFactor2explaining14%,ofthevarianceinresponses.ePDSQandPDQ-39scoreswerecorrelatedwiththe
UPDRS3 score (ρ =0.35, P < 0.001; and ρ =0.28, P < 0.001, respectively). Conclusion. e translated PDSQ and PDQ-39
questionnairesdemonstratedhighinternalconsistencyandcorrelationswithclinicalseverityofparkinsonismandatimedmotor
task, suggesting that they are valid tools for field-based epidemiological studies.
1. Introduction
eglobalimpactofParkinson’sdisease(PD)isexpectedto
reach pandemic proportions with the aging of both devel-
oped and developing country populations [1–4]. As life
expectancy on the African continent increases, neurode-
generative diseases are becoming a growing public health
concern. Population-based epidemiological studies of neu-
rodegenerative disease in Africa are rare, and there are
limited data from the 21
st
century [5]. Screening tools
designedandvalidatedinthedevelopedworld,primarilyin
English,arenotappropriateformuchofAfricawherethere
are hundreds of local languages and dialects [6], making
screening for PD or parkinsonism using questionnaires
validated in countries such as the USA and the UK
challenging.
South Africa has the second largest economy in Africa
[7] and a predominantly black population with increasing
lifeexpectancy[8].ecountryhasadynamicacademicand
healthcare environment and the skills and infrastructure to
conductworld-classscholarlyactivitiesandprovidemodern
healthcare services. ere are 11 official languages, and PD
Hindawi
Parkinson’s Disease
Volume 2020, Article ID 7542138, 9 pages
https://doi.org/10.1155/2020/7542138