Evidence is insufficient because of: 1  The limited number or size of studies. 2  Important flaws in study design or methods. 3  Inconsistency of findings across individual studies. 4  Gaps in the chain of evidence. 5  Findings not generalizable to routine primary care practice. 6  Lack of information on important health outcomes.
Definition of jerk for English Language Learners. : 1  a stupid person or a person who is not well-liked or who treats other people badly. : 2  a quick pull or twist. : 3  a sudden sharp movement.
Definition of jerk. 1  transitive verb. 2  1 : to give a quick suddenly arrested push, pull, or twist to jerk a rope. 3  2 : to propel or move with or as if with a quick suddenly arrested motion jerked the door open. 4  3 : to mix and serve (drinks, such as sodas) behind a soda fountain. 5  intransitive verb.