The goal of the field test was to collect data on the ASCQ-Me questions that would be analyzed to identify the best questions to include in the ASCQ-Me item banks and short forms. The procedures for the data analysis are detailed elsewhere. This section describes how the data were collected.
Seven field test sites from across the United States participated in ASCQ-Me. Sites were chosen based on their geographic diversity and variation in patient population characteristics. These locations included two community-based organizations, three academic medical centers, and two clinical sites. Each field test site was required to have:
- A substantial population of adults with sickle cell disease (to allow the recruitment of a minimum number of participants)
- Institutional Review Board (IRB) approval for participation. AIR’s IRB served as the governing IRB for sites without their own IRB.
- At least three computers with audio and access to high-speed internet service, which were available to respondents for three-hour increments.
Each field test site assigned a site coordinator, who was responsible for IRB submissions at that site, recruitment of participants, and assisting each participant in completing the survey. All site coordinators were trained in study procedures by members of the ASCQ-Me research team to ensure uniform data quality. The training covered participant recruitment, informed consent, and the ASCQ-Me web survey protocol and instructions.
Two approaches were used for participant recruitment. First, the sites used existing clinical relationships with SCD patients in the area and recruited these patients to take the survey at their clinic or location. The second approach was a snowball recruitment technique: at the completion of the survey, patients were asked to let others with sickle cell disease (SCD) know about the project and ask them to contact the clinic if they would like to participate.
Data Collection Procedure
When participants arrived to complete the survey, site coordinators explained the process and asked them to sign a consent form prior to beginning the survey. The field test of ASCQ-Me was conducted via a web-based survey hosted on an AIR web server. After the site coordinator logged into the ASCQ-Me website, a unique respondent ID was created for the participant. The site coordinator helped the respondent to log in to ASCQ-Me and gave assistance where needed in completing the survey.
The ASCQ-Me data analysis (specifically deriving item-level calibrations using a two-parameter graded response model) would require 500 completes and so the ASCQ-Me Research Team set its target total data collection for 550 to accommodate a ten-percent missing data rate. This was a very ambitious target because the adult SCD population is difficult to access, but the entire AIR research team worked hard to support the sites in exceeding this data collection target. This help included assisting with the data collection and recruiting new field test sites when the original sites were not able to meet target levels of recruitment.
The ASCQ-Me research team, led out of AIR, included San Keller, Manshu Yang, Roger Levine, Christian Evensen, Tamika Cowans, Corrina Moucheraud, and Maureen Maurer from AIR, Marsha Treadwell of UCSF Benioff Children’s Hospital of Oakland, Kathryn Hassell of the University of Colorado School of Medicine, and Ellen Werner of the National Heart Lung and Blood Institute.
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