Justification B (v2)

Survey of Chronic Gastrointestinal Illness in Persian Gulf Veterans

(Irritable Bowel Syndrome-Diarrhea)

VA Form 10-21092a,b,c OMB 2900-XXXX

B. COLLECTIONS OF INFORMATION EMPLOYING STATISTICAL METHODS

1. Provide a numerical estimate of the potential respondent universe and describe any sampling or other respondent selection method to be used. Data on the number of entities (e.g., households or persons) in the universe and the corresponding sample are to be provided in tabular format for the universe as a whole and for each strata. Indicate expected response rates. If this has been conducted previously include actual response rates achieved.

There are approximately 700,000 military personnel (i.e., potential respondent universe) who were deployed in the first Persian Gulf War. We will contact an estimated 4,000 (random selection) PG Veterans to complete this survey on the burden of GI symptoms. According to literature review, the prevalence rate of IBS is approximately 10%. From these 4,000 PG Veterans, 354 will be recruited for the evaluation of whether SBBO is associated with IBS-diarrhea in PG Veterans (Objective #2) and 140 of these participants will be randomly assigned to the treatment arm (Objective #3). We anticipate a response rate of 50%.

2. Describe the procedures for the collection of information, including:

   1. Statistical methodology for stratification and sample selection

   2. Estimation procedure

   3. Degree of accuracy needed

   4. Unusual problems requiring specialized sampling procedures

   5. Any use of less frequent than annual data collection to reduce burden

This is a purposive sample that targets PG Veterans; therefore no statistical methodology is used for stratification/sample selection. Additionally, we are not anticipating unusual problems that require specialized sampling procedures nor will we be using less frequent than annual data collection to reduce burden.

3. Describe methods to maximize response rate and to deal with issues of non-response. The accuracy and reliability of information collected must be shown to be adequate for intended uses. For collections based on sampling, a special justification must be provided for any collection that will not yield “reliable” data that can be generalized to the universe studied.

Initially, we will send an introductory letter to PG Veterans informing them of a survey that will be mailed to them and requesting their volunteered participation. A second letter will be mailed to non-responders 2 weeks later requesting their response. Non-respondents will then be followed up with telephone calls to inquire about their desire to participate in the study and to answer any questions they may have. We have the Salt Lake City Veterans Affairs and University of Utah Institutional Review Board (IRB) approval to conduct this study.

4. Describe any tests of procedures or methods to be undertaken. Testing is encouraged as an effective means of refining collections to minimize burden and improve utility. Tests must be approved if they call for answers to identical questions of 10 or more individuals.

There are no tests of procedures or methods to be undertaken.

5. Provide the name and telephone number of individuals consulted on statistical aspects of the design and the name of the agency unit, contractor(s), grantee(s), or other person(s) who will actually collect and/or analyze the information for the agency.

Rebecca Campo PhD.

Research Health Science Specialist

George E. Wahlen VA Medical Center

801-582-1565 ext.1993

Gregory J. Stoddard, M.P.H.

Co-Director, University of Utah Study Design and Biostatistics Center

Statistician, George E. Wahlen VA Medical Center

801-582-1565