Validity and Reliability of the Iranian Version of the Insomnia Severity Index

Background: The Insomnia Severity Index (ISI) is a short subjective questionnaire which helps physicians in making decisions about patients suffering from insomnia. The present study was an attempt to test the reliability and validity of the Iranian version of the ISI and to measure the correlation between ISI items and polysomnography results in chronic insomnia patients. Methods: Two groups responded to the Persian translation of four questionnaires; ISI, Pittsburg Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and General Health Questionnaire (GHQ). The first group consisted of 135 patients diagnosed with chronic insomnia, and the second group was comprised of 55 normal people. After completing the questionnaires, the insomniac patients underwent standard overnight polysomnography. Results: The internal consistency demonstrated by Cronbach’s alpha coefficient was above 0.8 for both groups. The Intra-class correlation coefficient was above 0.7 after two weeks for both groups. The correlations between ISI, PSQI, ESS, and GHQ were high. In addition, close correlations were found between scores obtained from the ISI questionnaire items in insomniac patients with corresponding polysomnographic variables. Conclusion: The Iranian version of the ISI is a reliable and valid instrument. It is a valuable short and first-line questionnaire for insomnia research and clinical work.

[Respiratory disorders of symptoms workers with exposure to organophosphates materials]

Organophosphate pesticides are widely used for agricultural pest control. Recent studies have linked pesticide exposure to respiratory symptoms and spirometry abnormalities. Regular use of appropriate personal protective equipment could protect workers from adverse respiratory health effects. This study explores the prevalence of chronic respiratory symptoms and ventilatory function among workers with occupational exposure to organophosphate pesticides. An interviewer-administered questionnaire was used to collect information on sociodemographic characteristic, smoking profile and history of respiratory health among 134 worker at a orgnophosphate production plant [exposed group], and workers occupationally unexposed to dust, fumes and gases [unexposed group]. Pulmonary function was assessed for both groups. A higher percentage of the exposed workers reported recurrent and prolonged respiratory symptoms including cough [17%], phlegm [19%], wheeze [6%], dyspnoea [9%], shortness of breath [7%] and bronchial asthma [4%]. Among the unexposed, prevalence of these symptoms were 9, 11, 1, 2, 4, and 1%, respectively. FVC, FEV1, and FEV1/FVC were significantly lower in the exposed workers compared with unexposed workers. Logistic regression analysis showed that the risk of respiratory symptoms increased 3.6 fold in organophosphate workers when compared to controls. This study suggests an increase of adverse respiratory health effects [reduction in lung function and a rise in respiratory symptoms] in workers with organophosphate exposure. We conclude that long term exposure to organophosphate is associated with chronic or permanent restrictive lung disease. This phenomenon was not observed in the control group