Following the identification of group members’ behaviours in the four modes, the community health clinical nurse
specialist must determine the stimuli causing those behaviours. Roy and Andrews (1999) described these
stimuli as focal, contextual, and residual. The focal stimulus is one that immediately influences a behaviour. Contextual stimuli include all the other stimuli present that contribute to the effects of the focal stimulus. The other stimuli present in the environment, which cannot be validated, are called residual stimuli