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.
verb (used with object) 1. to tug or pull at with a quick, short movement; pluck: She twitched him by the sleeve. 2. to jerk rapidly: The rider twitched the reins a couple of times. 3. to move (a part of the body) with a sudden, jerking motion. 4. to pinch or pull at sharply and painfully; give a smarting pinch to; nip.