In-group bias

Skewing your evaluation of data In favor of your group identification—whether defined by race, gender, belief system, or in other ways. A setup for in-group bias. 

At week 14, all rats dosed with 2mg/kg/day NTBC which showed the presence of ocular lesions were divided into groups A and B (continued dosing and discontinued dosing respectively) and were placed on a recovery phase of the study until termination at week 21. Allocation to group A or B was by alternate ear number in order to eliminate bias. Two rats dosed at 2mg/kg/day had normal eyes at week 14 and were placed in group A. All rats in the recovery phase (groups A and B) were terminated at week 21. All other rats were terminated at week 14. 

Spatial and/or coordinative bias can be introduced into a reaction substrate by coupling it to an auxiliary or controller group, which may be achiral or chiral. The use of chiral controller groups is often used to generate enantioselectively the initial stereocenters in a multistep synthetic sequence leading to a stereochemically complex molecule. Some examples of the application of controller groups to achieve stereoselectivity are shown retrosynthetically in Chart 19. 

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