B910 : Environmental Health

• The primary aim of the study was to determine the presence of acute and chronic respiratory disease among the residents of lower Manhattan. Therefore usage of cohort health study allowed the researchers to conduct such comparisons among different places and for multiple health outcomes (Lin et al., 2005).
• As the study was conducted over entire New York, to assemble and include such huge population, cohort study was appropriate.
• As the study compared the huge population with or without breathing issues, the chances of bias were maximum, hence, cohort study helped to lower the present bias (Lin et al., 2005).

2. The type of bias that were involved in the study are:

• As the research had lower response rate due to an emotional aspect, the research has selection bias.
• As there is a chance that participants reported more than one symptoms at the time of reporting, the research also had reporting bias.
• The third bias could be of misclassification bias in which some unidentified group took part in the study that affected the study results (Lin et al., 2005).

B. To design this cohort research study, the researchers decided two areas to conduct the survey and then sent 9168 surveys to the affected area whereas, 962 packets of survey in controlled area. Therefore, this study was helped to compare the data collected from both the areas and determine the health status of affected areas to that of the control area. This was the study and the study design which was used to address the explanation (Lin et al., 2005).

References:

Kwan, M. Y., Cairney, J., Faulkner, G. E., & Pullenayegum, E. E. (2012). Physical activity and other health-risk behaviors during the transition into early adulthood: a longitudinal cohort study. American journal of preventive medicine, 42(1), 14-20.

Lin, S., Reibman, J., Bowers, J. A., Hwang, S. A., Hoerning, A., Gomez, M. I., & Fitzgerald, E. F. (2005). Upper respiratory symptoms and other health effects among residents living near the World Trade Center site after September 11, 2001. American journal of epidemiology, 162(6), 499-507.