VA SOS Studies

How good is the data collected by the VA SOS Modified Method?

To view the validation study conducted by Sarah Engel and Reese Voshell that evaluate the traditional SOS method (the National IWLA method) and developed the Modified VA SOS method click on the link below. The study has been published in American Entomologist and we have been given permission (through Dr. Voshell) for unlimited distribution of the article.

Please note, this file is about 732 kb, it may take a while to download. If you have trouble with the download, please contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Volunteer Biological Monitoring: Can It Accurately Assess the Ecological Condition of Streams? Sarah R. Engel and J. Reese Voshell, Jr.. 2002. American Entomologist 48 (3): 164-177.

Follow-up validation studies completed in 2006

Virginia Tech Study on Modified Method as compared to VA-SCI

Virginia Commonwealth University Study on VA SOS Modified Method in Piedmont Streams of Virginia