[Fr. riule fr. L. regula, ruler, pattern]
A guide or principle based on experience or observation.

ABCD rule

A clinical prediction value that estimates the likelihood of stroke in a patient who has had a transient ischemic attack. Its elements include: A (age greater than or less than 60); B (blood pressure above 140 mm Hg systolic or 90 diastolic); C (clinical features such as one-sided body weakness or speech disturbance); and D (duration of symptoms: 60 min, 10-60 min, or less than 10 min).
SYN: SEE: ABCD 2 score

buccal object rule

A dental radiographical technique used to identify the position of an object within a three-dimensional area. A reference radiograph is taken. The projection angle is changed and the resulting radiograph compared with the reference radiograph. If the image remains in the same position, the object is located buccal to the reference object. If the image changes position, the object is lingual to the reference object.

CHIP rule

A diagnostic prediction rule used to determine if a patient with a minor head injury would benefit from emergent CT imaging of the brain. Low-risk patients are those who have a Glascow Coma Scale (GCS) of 15, and no history of loss of consciousness, amnesia, vomiting, or generalized headache. These patients do not need neuroimaging in the Emergency Department, and can be discharged home with follow-up. Patients who are over 60 years old, or who have a history of alcohol or drug use, epilepsy, or coagulopathy are considered high risk regardless of their GCS. Patients with intermediate findings are considered to have medium-risk mild head injuries.

Cieszynski rule

SEE: Cieszynski rule

Clark rule

SEE: Clark rule

Common Rule

Any of the U.S. policies designed to protect the rights and interests of citizens who choose to participate in government-funded biomedical research. Those who choose to participate in biomedical research often suffer from life-altering or life-threatening illnesses. As a result they may be more psychologically vulnerable than others and may agree to become investigative subjects because of fear or desperation. The protections provided by the Common Rule are designed to ensure that agencies that perform federally funded human research respect the rights of experimental subjects. Included are the rights of confidentiality and full disclosure (informed consent). Research performed on children or prisoners is given special protections.

convex-concave rule

concave-convex rule A law of joint kinematics that states that if a convex joint surface moves on a stationary concave surface, the convex joint will slide in the direction opposite that of the angular motion of the bone, and that if a concave joint surface moves on a stationary convex surface, the articular surface will slide in the same direction as the angular motion of the bone.

Cowling rule

SEE: Cowling rule

decision rule

SEE: decision aid

Durham rule (of criminal responsibility)

A legal decision from Durham v. United States that limits the culpability of those with psychological or neurological diseases who have committed criminal acts. It states that an unlawful act is not a criminal act if it was committed by someone mentally ill, e.g., psychotic at the time, or was committed by someone with profound neurological disease, e.g., with severe dementia or organic brain injury.

learned intermediary rule

SEE: Learned intermediary doctrine.

mature minor rule

Any of the regulations in some states that allow the practitioner to treat minors without parental consent if the minor is deemed to be capable of understanding the nature and consequences of the treatment and if the treatment is of benefit to the minor.

modified Ottawa ankle rules

SEE: modified Ottawa ankle rules

rule of nines

A formula for estimating percentage of body surface areas, particularly helpful in judging the portion of skin that has been burned. For the adult, the head represents 9%; each upper extremity 9%; the back of the trunk 18%, and the front 18%; each lower extremity 18%; and the perineum the remaining 1%.

Descriptive text is not available for this image

Descriptive text is not available for this image


Ottawa ankle rules

SEE: Ottawa ankle rules

prediction rule

Any rule for establishing the probability that a disease is present.

rule of rescue

The tendency of individuals to make lifesaving decisions on behalf of people who present in dire circumstances, without reference to the potential costs, harms, hazards, or risks that such heroic acts may pose to themselves or to their community.

rule of ten

The criteria used to judge the readiness of an infant for surgical repair of a cleft lip. The infant must weigh 10 lb, be 10 weeks old, have a hemoglobin value of 10 g, and have a white blood cell count less than 10,000.

rule of thirds

The classification of bone shaft fractures: proximal third, midshaft, and distal third. Midshaft fractures heal more slowly than other fractures because the blood supply in the middle of a bone is less than that at either end.

van't Hoff rule

SEE: van't Hoff, Jacobus Henricus