Repository of Research and Investigative Information

Repository of Research and Investigative Information

Ilam University of Medical Sciences

The prevalence of tropia, phoria and their types in a student population in Iran

Fri Apr 19 12:54:13 2024

(2020) The prevalence of tropia, phoria and their types in a student population in Iran. Strabismus. pp. 35-41. ISSN 0927-3972

Full text not available from this repository.

Official URL:


Purpose: The aim of this study is to determine the prevalence of tropia, phoria, and their types in Islamic Azad University students in Shahrekord, Iran. Methods: Of 826 students that were invited, 752 participated in this cross-sectional study (response rate = 91.04). After applying exclusion criteria, statistical analyses were performed on the data of 726 individuals. All participants underwent optometric tests including measurement of visual acuity, objective and subjective refraction, as well as binocular vision and ocular health examinations. The unilateral and alternate cover tests were done to detect the tropia and phoria at 6 m and 40 cm, respectively. Results: The overall prevalence and 95 confidence interval (CI) of tropia, exotropia, and esotropia were 1.5 (0.8 to 2.7), 1.2 (0.6 to 2.4), and 0.3 (0.1 to 1.1), respectively. The prevalence of esotropia was significantly higher in older age groups (24 years old) (p = .040) . The prevalence of exotropia was significantly higher in females (0.039) and in myopic individuals (p = .001). The overall prevalence and 95 CI of phoria, exophoria, and esophoria were 12.9 (10.7 to 15.6), 11.7 (9.6 to 14.3), and 1.2 (0.6 to 2.3), respectively. There was a significant difference in the overall prevalence of exophoria according to the age (0.021). The prevalence of esophoria was significantly higher in females (p = .039). The prevalence of exophoria was significantly higher in myopic participants (p = .003). Exophoria and exotropia were the most common types of phoria and tropia, respectively. Conclusion: The prevalence of strabismus in university students was similar to the Iranian general population but lower than other countries. One in every 10 students had phoria, which was much lower than similar reports on Iranian populations; however, due to near-work activity, these students are prone to asthenopia, early visual fatigue, and decreased productivity. Therefore, it is suggested that university students also undergo screening programs to detect the cases of tropia and phoria.

Item Type: Article
Ostadimoghaddam, H.UNSPECIFIED
Aghamirsalim, M.UNSPECIFIED
Khabazkhoob, M.UNSPECIFIED
Keywords: Strabismus Tropia Phoria Cross-sectional study Iran psychosocial-aspects strabismus amblyopia children schoolchildren preschool Ophthalmology
Page Range: pp. 35-41
Journal or Publication Title: Strabismus
Journal Index: ISI
Volume: 28
Number: 1
Identification Number:
ISSN: 0927-3972
Depositing User: مهندس مهدی شریفی

Actions (login required)

View Item View Item