The SRAS has 20 four-choice questions and is based on the physical-emotional symptoms of anxiety, which William Zank developed in 1971 (
20). The most frequent symptoms of anxiety disorders were utilized as diagnostic criteria to create this scale. In the beginning, the clinical interviews of the anxious clients were recorded in detail, and later, they used every item mentioned in the construction of the test. The diagnostic criteria of SRAS are five emotional symptoms and 15 physical symptoms. Compared to other questionnaires, the advantage of the Zung anxiety questionnaire is that the respondents cannot follow a particular method in their answers. Several questions (sixteen questions) emphasize positive symptoms because of the 20 questions used in SRAS, and the rest (four questions) emphasize negative symptoms (
20). Regarding the validity of the SRAS questionnaire, there have been various studies that show that this scale consistently differentiates anxiety disorders from other categories at a statistically significant level. One of these studies on the correlation between Hamilton's anxiety scale (1959) and SRAS showed that based on the information obtained from the implementation of the two scales on more than 500 cases and using the Pearson correlation method, the correlation between the two mentioned tests was equal to 71% (
21). The coefficient of coherence method, which examines the degree of internal correlation, was used to calculate the reliability of the SRAS scale. In addition, the statistical analysis of SRAS results using the coefficient of coherence method showed a coefficient equal to 84, indicating this scale's very high reliability (
22).