title: Letter in response to Picillo et al., in relation to Szewczyk-Krolikowski et al.: the influence of age and gender on motor and non-motor features of early Parkinson's disease: initial findings from the Oxford Parkinson disease Center (OPDC) discovery cohort.
authors.affiliation: School of Social and Community Medicine, University of Bristol, United Kingdom.
authors.forename: Y
authors.initials: Y
authors.lastname: Ben-Shlomo
authors.affiliation: School of Social and Community Medicine, University of Bristol, United Kingdom.
authors.forename: M
authors.initials: M
authors.lastname: Lawton
authors.affiliation: Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, University of Oxford, United Kingdom.
authors.forename: K
authors.initials: K
authors.lastname: Szewczyk-Krolikowski
authors.affiliation: Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, University of Oxford, United Kingdom; Oxford Parkinson Disease Centre, University of Oxford, United Kingdom; Department of Clinical Neurology, John Radcliffe Hospital, Oxford, United Kingdom. Electronic address: michele.hu@ndcn.ox.ac.uk.
authors.forename: M T
authors.initials: MT
authors.lastname: Hu
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D010300:Parkinson Disease / Q000150:complications* / Q000453:epidemiology*