Iranian Journal of

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Background and Objectives: Noise-induced hearing loss is a prevalent work-related morbidity in the country. We determined the strength of association between hearing loss and occupational noise exposure as the first step in prevention programs.
Material and Methods: A historical cohort study involving 100 exposed and 31 non-exposed subjects was conducted. Noise exposure was estimated using sound level meter BSEN 60651, Type 2. Past noise exposure was estimated using the existing data on the place and type of work. Audiometry was used to assess hearing loss in each subject in 3- year intervals on an occupational cohort from 1993-2004.

Results: Noise-induced hearing loss was found in 49% (49 subjects) of the exposed group and 9.7 %( 3 subjects) of non-exposed group (p<.0001). Nobody used any form of hearing protection routinely in either group. Relative risk for noise-induced hearing loss was 5.1(CI95%: 1.7- 15.1).Time at risk was estimated 24.9 years (22.7-27.1) in exposed and 22.2 years (20.7-23.7) in unexposed group by survival analysis.
Conclusion: More legislation, hearing conservation programs, and surveillance and biological monitoring of work sites and workers are required to prevent occupational hearing loss. Planning strategies for noise assessment and control can help improve the work environment. Gross occupational exposure to noise has been demonstrated to cause hearing loss and the authors believe that occupational hearing loss in the country is a widespread problem.

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Background & Objectives: Tuberculosis (TB) is one of the major infectious diseases in Iran and has pulmonary and extra-pulmonary manifestations. Considering the differences in the distribution of the cases across different regions, we decided to study the geographical distribution, epidemiologic characteristics, and disease pattern in Lorestan.

 Methods: This ecologic (descriptive analytical) survey was done in Lorestan between 2002 and 2008. The data was collected from the Health Department of Lorestan University of Medical Sciences and included the history of 1481 patients suffering from TB. The study variables were sex, disease type, residential location, age, and year. The data were analyzed using statistical package SAS 9.2 and descriptive and inferential statistics were applied.

Results: From 1481 registered patients 58.4% were male and 41.6% were female among which 68.74% and 29.98% lived in urban and rural areas and 1.28% were nomads. The mean age of the patients was 41.87. The highest and lowest incidence rates were observed in Khoram Abad (19.38 per 100000) and Azna (7.04 per 100000), respectively. Using Poisson regression, it was observed that the effects of age structure and residency on the incidence rate were significant.

Conclusion: The percentage of nomads was identified as the most important demographic factor in the incidence rate of TB in Lorestan. Allocation of better resources and appropriate training can be effective in controlling and preventing the disease.

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Background and Objectives: The study aimed to analysis the psychometric properties of the health system resilience scale, assessing it and to introduce a conceptual model for qualitative analysis of Iran health system in the face of the civid-19 crisis.
 
Methods: In this Mixed-method study, the determination of face and content validity was performed using 8 experts. The structure validity was investigated in a cross-sectional study through an electronic survey of 178 actors in the Iran health system. Resilience has been assessed in five dimensions using 5point Likert scale.
 
Results: The percentage mean score of the Iranian health system resilience in the face of the Covid19 crisis was 41/08 and in the moderate level. The percentage mean score (standard deviation) for 5 dimension include awareness 39/2 (21), diversity 38/7 (21), self-regulation 36 (20/6), integration 39/9 (21/5) and adaptation 41/2 (21/8). Confirmatory factor analysis indicated the appropriate fit of the information with the five-component structure.
 
Conclusion: The maximum score of resilience dimension belongs to adaptation and the lowest to the self-regulation indicating that it requires interventions to involve the private sector, and to design a new delivery system for crisis situations. The questionnaire can be used as a standard instrument for assessing the health system resilience.