Prediction of Neurocognitive Deficits by Parkinsonian Motor Impairment in Schizophrenia: A Study in Neuroleptic-Naïve Subjects, Unaffected First-Degree Relatives and Healthy Controls From an Indigenous Population.

Background: Neurocognitive deficits are among the most debilitating and pervasive symptoms of schizophrenia, and are present also in unaffected first-degree relatives. Also, multiple reports reveal parkisonian motor deficits in untreated subjects with schizophrenia and in first-degree relatives of affected subjects. Yet, the relation between motor and cognitive impairment and its value as a classifier of endophenotypes has not been studied.

Research with spanish-speaking populations in the United States: lost in the translation. A commentary and a plea.

Verbal material used to assess the cognitive abilities of Spanish-speakers in the the United States is frequently of linguistically unacceptable quality. The use of these materials in research settings is thought to pose a serious threat to test validity and hence to the validity of claimed results or conclusions. The authors explain how and why incorrect language finds its way into cognitive tests used in research and other settings and suggest solutions to this serious problem.