ORIGINAL ARTICLE Cross-Cultural Psychometric Assessment of the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) Pain Scale in the Portuguese Population Margarida Barbosa, MD* ,† ; Michael I. Bennett, MD, FRCP, FFPMRCA § ; Ramiro Verissimo, MD, PhD ¶ ; Davide Carvalho, MD, PhD †,‡ *Chronic Pain Unit, Department of Anaesthesiology, Centro Hospitalar de S~ ao Jo~ ao, Porto, Portugal; † Faculty of Medicine, University of Porto, Porto, Portugal; ‡ Department of Endocrinology, Diabetes and Metabolism, Centro Hospitalar de S~ ao Jo~ ao, Porto, Portugal; § Unit of Palliative Care, Leeds Institute of Health Sciences, School of Medicine, University of Leeds, Leeds, U.K.; ¶ Department of Psychology, Faculty of Medicine, University of Porto, Porto, Portugal & Abstract Background: Chronic pain is a well-known phenomenon. The differential diagnosis between neuropathic and nocicep- tive pain syndromes is a challenge. Consequently, assessment instruments that can distinguish between these conditions in a standardized way are of the utmost importance. The Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) is a screening tool developed to identify chronic neuropathic pain. The aim of this study was the Portuguese language translation, linguistic adaptation of the LANSS pain scale, its semantic validation, internal consistency, temporal stability, as well its validity and discriminative power. Methods: LANSS Portuguese version scale was applied to 165 consecutive patients attending the pain clinic: 103 fulfilled the clinical criteria for the diagnosis of pain of neuropathic origin and the remaining 62 fulfilled the criteria for nociceptive pain. Results: The scale proved to be an internally consistent (Cronbach’s alpha = 0.78) and reliable instrument with good test–retest stability (r = 0.7; P < 0.001). However, its validity and specificity with a cutoff point of ≥ 12, for differentiating patients with neuropathic pain from those with non-neuro- pathic pain, had 89% sensitivity, 74% specificity, positive predictive value of 85%, and negative predictive value of 81%. Conclusions: The Portuguese LANSS version pain scale properties lead us to the conclusion that such a cross- cultural version is a reliable and valid instrument for the differentiation of this type of pain. Its usage is recom- mended. & Key Words: LANSS, cross-cultural comparison, reliability, validity, neuropathic pain INTRODUCTION Neuropathic pain definition was recently changed by International Association for the Study of Pain to “pain arising from a direct consequence of a lesion or disease Address correspondence and reprint requests to: Margarida Barbosa, MD, Chronic Pain Unit, Centro Hospitalar de S~ ao Jo~ ao, Al Hern^ ani Monteiro, Porto 4200-319, Portugal. E-mail: kika_barbosa@mail.com. Submitted: July 02, 2013; Revision accepted: August 15, 2013 DOI. 10.1111/papr.12118 © 2013 World Institute of Pain, 1530-7085/13/$15.00 Pain Practice, Volume 14, Issue 7, 2014 620–624