Rate of validity, reliability and difficulty indices for teacher-designed exam questions in first year high school

The purpose of the research is to determine high school teachers’ skill rate in designing exam questions in mathematics subject. The statistical population was all of mathematics exam shits for two semesters in one school year from which a sample of 364 exam shits was drawn using multistage cluster sampling. Two experts assessed the shits and by using appropriate indices and z-test and chi-squared test the analysis of the data was done. We found that the designed exams have suitable coefficients of validity and reliability. The level of difficulty of exams was high. No significant relationship was found between male and female teachers in terms of the coefficient of validity and reliability but a significant difference between the difficulty level in male and female teachers was found (P<.001). It means that female teachers had designed more difficult questions. We did not find any significant relationship between the teachers’ gender and the coefficient of discrimination of the exams.