Validity and reliability of a questionnaire to investigate people prone to accidents in different industries.

Objectives. In recent years, workplace accidents have imposed a considerable cost on industries. Accident proneness is one of the most influential factors known to cause unsafe behaviors and occupational accidents. Therefore, the present study investigated the validity and reliability of the accident proneness questionnaire in industries. Methods. The questionnaire was developed to measure accident proneness in industries - the developed instrument was distributed in East Azarbaijan industries (1100 questionaries). Content validity, confirmatory factor analysis and exploratory factor analysis were used to examine the construct validity, and Cronbach's α and the test-retest method were used to examine the reliability and reproducibility of the instrument. Results. In the face validity section, the impact score of all items was determined to be >1.5. In the content validity section, the content validity index (CVI) and the content validity ratio (CVR) were higher than the standard value of 0.42. The Cronbach's α coefficient for all dimensions was 0.914. Conclusion. The findings of the study show that the accident proneness questionnaire in industries has acceptable validity and reliability, and can be used as a comprehensive, practical, robust and reliable instrument to investigate the accident proneness of different industries.

Comparative study of the sealing ability of the lateral condensation technique and the BeeFill system after canal preparation by the Mtwo NiTi rotary system.

The purpose of this in vitro study was to compare the sealing ability of the lateral condensation technique and the BeeFill system after canal preparation by the Mtwo rotary system. Forty extracted single-rooted teeth were prepared by using the Mtwo rotary system. The teeth were then divided into 2 experimental groups (n = 15 each) and 2 control groups (n = 5 each). The specimens in groups 1 and 2 were obturated using the lateral condensation technique and the BeeFill system, respectively. The teeth in the negative control group were also obturated with the lateral condensation technique, and the specimens in the positive control group were not root-filled. The specimens were then immersed in an aqueous solution of 2% China ink for 1 week, after which the roots were cleared and the linear extent of dye penetration was measured with a stereomicroscope by 2 endodontists. The data collected were then analyzed by using the 1-sample Kolmogorov-Smirnov test and independent t test, with a significance level of P < or = 0.05. Although the mean (+/- standard deviation) dye leakage in the BeeFill thermoplasticized injection group was less than that in the lateral condensation group (1.497 +/- 0.7 vs. 2.521 +/- 1.733), there was no significant difference between the experimental groups on the parametric independent t-test (P = 0.209).