CORRECTION
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J Weuve, K T Kelsey, J Schwartz, *et al*. Delta-aminolevulinic acid dehydratase polymorphism and the relation between low level lead exposure and the Mini-Mental Status Examination in older men: the Normative Aging Study. ([Occup Environ Med 2006;63:746–53](http://oem.bmj.com/lookup/volpage/63/746)). Reference 4 is incorrect and should read Bleeker ML, Lindgren KN, Ford DP. Differential contribution of current and cumulative indices of lead dose to neuropsychological performance by age. *Neurology* 1997:**48**:639–45.