Instruments
State-Trait Anxiety Inventory (STAI): The STAI, developed by Spielberger et al., consists of two parts with 20 items: the STAI-1, which measures the state anxiety level, and the STAI-2, which measures the trait anxiety level20. The scale is a four-point Likert-type scale with possible answers of “not at all,” “a little,” “a lot,” and “completely.” The STAI contains two types of statements. Positive (direct) expressions express negative emotions, while negative (inverted) expressions express positive emotions. Negative statements in the STAI-1 (state anxiety) are items 1, 2, 5, 8, 10, 11, 15, 16, 19, and 20. Negative statements in the STAI-2 (trait anxiety) are items 21, 26, 27, 30, 33, 36, and 39. Separate total weights of direct and inverted expressions are calculated and the sum of inverse expressions is subtracted directly from the sum of expressions. A predetermined and unchanging value is added to that number. This constant value is 50 for the STAI-1 and 35 for the STAI-2. The last value obtained is the anxiety score of the individual. If more than 3 statements are not answered from among the scale’s 20 items, the form is considered invalid. The scores obtained from both scales theoretically vary between 20 and 80, where a high score indicates a high level of anxiety.