Current Evidence on Age-Related Changes in Levels of Testosterone in Men

question 25

Multiple Choice

Current evidence on age-related changes in levels of testosterone in men indicates that _______.

• A) there is a large and steady decline beginning at about age 40
• B) there is a large decline, but it begins only after about age 60
• C) there is no decline at all
• D) there is a small and gradual decline from midlife onward

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Definitions:

Internal Validity

The degree to which a study can demonstrate a causal relationship between variables, free from the contamination of other variables that might confound the results.

External Validity

The degree to which a study's findings can be applied to different contexts and diverse individuals.

Generalizability

The extent to which research findings and conclusions can be applied to broader populations or different contexts beyond the study sample.

Intervention

An action or process of intervening, usually aimed at producing some kind of change or improvement in a situation.