X-rays in a medical laboratory Thesis

Applications of SDT

SDT can be used in conditions where people need to determine the presence or absence of certain signals. It has widespread applications ranging from detecting auditory tones in a research laboratory to reading X-rays in a medical laboratory.

One important measure in SDT is that of response bias. Depending on the conditions, people might be willing to report the presence of a stimulus even if they’re not sure about it. Other situations might require a person to be more conservative—reporting hits only if they’re absolutely sure that a signal is present.

Response bias can be manipulated by:

• Payoffs

• Motivation

• Sensitivity Levels

Payoffs: For instance, radiologists might have a bias to report tumors even when they are not absolutely sure that the target spot is a tumor. This approach may cause them to report false alarms; however, underreporting tumors could result in higher rates of patient deaths and potential lawsuits. Therefore, a radiologist is motivated to report tumors.

Motivation: For instance, a basic hearing assessment test requires patients to indicate if they heard a tone or not. Tones are usually present in about half the trials. Some patients could be motivated to show that they have normal hearing and report that they hear a tone on every trial.

Sensitivity Levels: For instance, airport security screeners at security checkpoints are expected to constantly be alert in detecting weapons concealed in carry-on baggage. Since people do not frequently carry weapons in their bags and screeners do not often detect concealed weapons in passengers’ baggage, their sensitivity to detect weapons decreases.

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