Référence bibliographique 
Xiong, Lan, Montplaisir, Jacques, Desautels, Alex, Barhdadi, Amina, Turecki, Gustavo, Levchenko, Anastasia, Thibodeau, Pascale, Dubé, Marie-Pierre, Gaspar, Claudia et Rouleau, Guy A. 2010. «Family Study of Restless Leg Syndrome in Quebec, Canada: Clinical Characterization of 671 Familial Cases ». Archives of Neurology, vol. 67, no 5, p. 617-622.
« Restless legs syndrome is one of the few common neurological disorders that exhibit significant familial aggregation. The dissection of the underlying genetic and nongenetic composition of the outstanding familial aggregation observed in RLS should be interesting to all concerned physicians, geneticists, and epidemiologists. » (p. 620)
During 15 years, « [a] total of 249 probands and their relatives [n=892] were interrogated directly or indirectly [...] » (p. 618).
Type de traitement des données :
« The substantial familial clustering of restless legs syndrome (RLS) has long been recognized. However, there has been a lack of large-scale systematic family studies and of full descriptions of the clinical features of familial RLS (fRLS). A systematic family study, ie, the investigation of every family member individually instead of by family history through a proxy report, represents a more accurate approach to delineate a comprehensive clinical spectrum of the phenotypic manifestations and to estimate the relative recurrent risk ratio in relatives (ie, quantification of the familial aggregation). Currently, RLS remains a clinical diagnosis primarily based on patient self-report of subjective symptoms. Several objective measurements have been developed to confirm the RLS diagnosis. However, none of these tests has a 100% sensitivity and specificity for a definitive RLS diagnosis, and none has been systematically applied to large scale population or family studies because of the cost and impracticality of these approaches. » (p. 617)