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Type II errors may be having a significant impact on drug discovery. This is of particular importance in the clinical neurosciences, where endpoints are often subjective scores of disability rather than unequivocal events such as survival. Here we examine a recently published study [Lang AE, Gill S, Patel NK, et al. Randomized controlled study of intraputamenal glial cell-derived neurotrophic factor infusion in Parkinson disease. Ann Neurol 2006;59:459-66] in an area of immense importance to neuroscience. This small study found no detectable clinical benefit from infused intraputamenal GDNF as a treatment for Parkinson disease. However the standard deviation of the accrued data turned out to be considerably higher than had been anticipated in the power analysis performed prior to the study. In order to determine what impact, if any, this had on the conclusions that could be drawn, the actual data were analyzed by means of both the t-test and the rank-based Somers'D. The study was found to be underpowered and thus incapable of ruling out a large effect of GDNF on Parkinson disease. It therefore does not contradict the large effects seen in previous open-label studies.

Nymphal Ixodes scapularis Say, the vector of Lyme borreliosis, was most common in forested areas across Shelter Island, Suffolk County, New York, and least common in xeric habitats such as beach and grassland. At the scale of individual house yards, nymphs were most common at wooded edges of property and least common on lawns. The abundance of ticks at yard edges was positively correlated with numbers on lawns and in landscaping, suggesting that tick abundance in woods affects abundances in adjacent yards. Because 57% of all yard area is adjacent to woodlands on Shelter Island, public health efforts to reduce tick populations in wooded areas should supplement efforts by individual yard owners to decrease risk. Methods of tick control for woodlands should also be evaluated for their effect on tick populations in adjacent yard habitats.

Nymphal Ixodes scapularis Say deer ticks were collected at 22 parks or other natural areas on Long Island, New York, to examine the relationship between tick populations and geographic position, size of area, presence of white-tailed deer, Odocoileus virginianus (Zimmerman), and numbers of human Lyme disease cases in adjacent communities. Nymphal ticks were 93% less abundant when deer were absent and were also less common in smaller natural areas. Geographic position on Long Island was not important. Tick numbers were significantly correlated with human Lyme disease incidence in adjacent townships. A second survey of larval ticks from five areas where deer were absent and six where deer were present found larvae present at four of the five sites without deer, but at only 2% of the levels found where deer were present. These results suggest that populations of I. scapularis can occur and reproduce in the absence of white-tailed deer, so that eradication of all deer would greatly reduce, but not eliminate, all risk of Lyme disease.