Tachycardia
A heart rate that is faster than the normal range of a resting heart rate (typically 60-100 beats per minute). See also ventricular tachycardia, supraventricular tachycardia, and atrioventricular nodal reentry.

Tai chi
An exercise consisting of slow, rhythmic movements that emphasize trunk rotation, weight shifting, coordination, and gradual narrowing of lower extremity stance.

Target condition
In diagnostic test studies, the condition the investigators or clinicians are particularly interested in identifying (eg, tuberculosis, lung cancer, or iron-deficiency anemia).

Target endpoints
In intervention studies, the condition the investigators or clinicians are particularly interested in identifying and in which it is anticipated the intervention will decrease (eg, myocardial infarction, stroke, or death) or increase (eg, ulcer healing). See also Cohort study.

Target-negative
In diagnostic test studies, patients who do not have the target condition.

Target-positive
In diagnostic test studies, patients who do have the target condition.

Teach-back method
A technique to assess understanding in which the patients or family members are asked to restate what was just discussed.

Tension-type headache
A headache marked by mild to moderate pain of variable duration that affects both sides of the head. The pain can radiate from the neck, back, eyes, or other muscle groups in the body. This is the most common type of headache disorder.

Terminal cancer prognostic score
An index for predicting length of survival in terminally ill cancer patients.

Terminal care
Palliative care or care focused primarily on relieving pain and physical symptoms, enhancing psychosocial supports, and assisting patients and families to make the best possible decisions in the face of serious, potentially life-threatening illness, specifically for patients who are terminally ill.

Terminal delirium
Delirium in actively dying patients that is often untreatable and will eventually cease only with the patient’s death.

Tertiary care
Medical care provided to a patient when referred by one health professional to another with more specialized qualifications or interests. There are two levels of referred care: secondary and tertiary. Secondary care is usually provided by a broadly skilled specialist such as a general surgeon, general internist, or obstetrician. Synonymous with Referred care.

Tertiary care center
A medical facility that receives referrals from both primary and secondary care levels and usually offers tests, treatments, and procedures that are not available elsewhere. Most tertiary care centers offer a mixture of primary, secondary, and tertiary care services so that it is the specific level of service rendered rather than the facility that determines the designation of care in a given study. See also Referred care; Primary care.

Tertiary palliative care
The academic medical centers where specialist knowledge for the most complex palliative care cases is practiced, researched, and taught.

Test threshold
The probability below which the clinician decides a diagnosis warrants no further consideration. See also Treatment threshold.

Theoretical saturation
The point at which iterations among data collection, analysis, and theory development yield a well-developed concept, and further observations yield minimal or no new information to further challenge or elaborate the concept. See also Informational redundancy.

Theory
Theory consists of concepts and their relationships.

Theory triangulation
Theory triangulation is a process whereby emergent findings are corroborated with existing social science theories. See also Triangulation.

Threshold NNT
Maximum number needed to treat (NNT) or number needed to harm (NNH) accepted as justifying the benefits and harms of therapy. See also Test threshold.

Time-series design
In this study design, data are collected at several times both before and after the intervention; data collected before the intervention allow the underlying trend and cyclical (seasonal) effects to be estimated. Data collected after the intervention allow the intervention effect to be estimated while accounting for underlying secular trends. The time-series design monitors the occurrence of outcomes or endpoints over a number of cycles and determines whether the pattern changes coincident with the intervention.

Tinel sign
Paresthesias in the distribution of the median nerve when the clinician taps on the distal wrist crease over the median nerve.

Tokuhashi Revised Scoring System
Simple scoring system for the preoperative evaluation of the prognosis for patients with spinal metastases. (See also Chapter 10, Spinal Cord Compression in Patients With Advanced Metastatic Cancer, Table 10-2.)

Tomita Scale
Scale used in cases of spinal cord compression to assess patients’ function and neurologic status. The neurologic outcome for each patient is predicted based on pretreatment neurologic status, pathologic type, nature of block (level and structural vs tumoral), and result of repeat fluoromyelography. For more information, see the following article for the scale: Tomita T, Galicich JH, Sundaresan N. Radiation therapy for spinal epidural metastases with complete block. Acta Radiol Oncol. 1983;22(2):135-143. [PMID: 6310968]

TPN
Abbreviation for total parenteral nutrition, in which all nutrition and hydration is given through a central or peripheral vein.

Tracheoesophageal speech
An alternate method for speech production without oscillation of the vocal folds in patients who have had total laryngectomy for cancer. The sound is produced by releasing gases from or through the esophagus.

Transition programs
Volunteer-driven services provided for both community-dwelling patients and residents of long-term care facilities. Transition programs enable hospices to provide services to people with life-limiting illnesses when they are not eligible for hospice care.

Transjugular intrahepatic portosystemic shunt (TIPS)
Angiographic procedure performed under fluoroscopic guidance wherein a wire mesh stent is placed within the liver to decompress the portal circulation directly into the hepatic vein. Indications for placement include variceal bleeding and refractory ascites in patients with cirrhosis.

Traube space
Traube space is an anatomic region defined by the sixth rib superiorly, the anterior border of the spleen, and the costal margin inferiorly. Dullness to percussion over Traube's space may indicate splenomegaly, although this can be a normal finding in a patient with a full stomach and is more difficult to assess in obese patients.

Treatment effect
The results of comparative clinical studies can be expressed using various intervention effect measures. Examples are absolute risk reduction (ARR), relative risk reduction (RRR), odds ratio (OR), number needed to treat (NNT), and effect size. The appropriateness of using these to express an intervention effect and whether probabilities, means, or medians are used to calculate them depend on the type of outcome variable used to measure health outcomes. For example, ARR, RRR, and NNT are used for dichotomous variables, and effect sizes are normally used for continuous variables. See also Absolute risk reduction; Relative risk reduction; Odds ratio; Number needed to treat.

Treatment ranking
Ordering of treatments according to decreasing probability that they can produce better outcomes than competing interventions.

Treatment target
The manifestation of illness (a symptom, sign, or physiological abnormality) toward which a treatment is directed. See also Endpoint.

Treatment threshold
Probability above which a clinician would consider a diagnosis confirmed and would stop testing and initiate treatment. See also Test threshold.

Trial of therapy
In a trial of therapy, the physician offers the patient an intervention, reviews the impact of the intervention on that patient at some subsequent time, and, depending on the impact, recommends either continuation or discontinuation of the intervention.

Triangulation
1. More than one investigator collects and analyzes the raw data, such that the findings emerge through consensus among investigators. 2. In qualitative research, an analytic approach in which key findings are corroborated using multiple sources of information.

Trigger orders
Orders in response to which the computer decision support system (CDSS) would initiate action.

Trim-and-fill method
When publication bias is suspected in a systematic review, investigators may attempt to estimate the true intervention effect by removing, or trimming, small positive-result studies that do not have a negative-result study counterpart and then calculating a supposed true effect from the resulting symmetric funnel plot. The investigators then replace the positive-result studies they have removed and add hypothetical studies that mirror these positive-result studies to create a symmetric funnel plot that retains the new pooled effect estimate. This method allows the calculation of an adjusted confidence interval and an estimate of the number of missing trials.

True negative
Those whom the test correctly identifies as not having the target disorder.

True positive
Those whom the test correctly identifies as having the target disorder.

T-test
A parametric statistical test that examines the difference between the means of 2 groups of values.

Tuskegee Syphilis Study
Study conducted between 1932 and 1972 in Tuskegee, Alabama, by the US Public Health Service in which investigators recruited 399 impoverished black sharecroppers with syphilis for research related to the natural progression of the untreated disease in hopes of justifying treatment programs for blacks. It became extremely controversial and a prime example of unethical research because the investigators failed to treat the patients with penicillin, which had been validated as an effective cure for the disease after 1940.

Type I error
An error created by rejecting the null hypothesis when it is true (ie, investigators conclude that a relationship exists between variables when it does not).

Type II error
An error created by accepting the null hypothesis when it is false (ie, investigators conclude that no relationship exists between variables when, in fact, a relationship does exist).