Setting Participation was open to all community health centers not receiving categorical HIV-funding (from the federal Ryan White Program) in North Carolina, South Carolina and Mississippi. NACHC worked with primary care associations in each state to identify health centers that were highly motivated to implement routine HIV screening. Community health centers are often comprised of more than one clinical site, which was the case with all but one of the six centers participating in this effort. Participating centers did not receive any additional funding to support their transition to routine HIV testing, although rapid test kits were donated, and later in the project year, a small stipend from NACHC was provided to support confirmatory testing. Health centers began rolling out testing between December 2006 and April 2007 and submitted test documentation data for this study through March 31, 2008. For this analysis, we restricted data to the 13-month period between March 1, 2007 and March 31, 2008 when full implementation was underway. Institutional Review Board approval for the analysis was obtained from the University of California, San Francisco.
HIV Testing Algorithm The HIV testing algorithm was developed by the NACHC trainer after consulting with participating health centers and was included in the overall written protocol used in each clinic. Trained clinical staff members drew blood samples using a finger stick method. Samples were tested using the Uni-Gold Recombigen HIV screening test (Trinity Biotech USA, St. Louis, MO). Clinical staff reported negative results to patients as HIV-uninfected; positive results were reported as preliminary positive and staff gave patients written information about the nature of the result. At that time, patients were offered confirmatory testing, which was done with a western blot. If the western blot was negative, clinic staff asked patients to return after three months for a repeat western blot. Late in the year of implementation, NACHC was able to find some funding for two centers to conduct RNA testing in lieu of western blots.
After participating health centers were identified, the NACHC trainer worked with staff in each clinic to redesign patient flow procedures to integrate routine HIV screening with the primary care visit. Although the point in the visit when testing was offered differed across centers, in general, non primary care providers conducted the testing and delivered results when the test came back negative. In cases of preliminary positive results, a primary care provider delivered the result. Clinic-specific procedures were documented in written protocols, which were used during clinic-wide in-service and role-specific training for primary care providers, social workers, and nurses. Training topics included how to offer HIV screening, discuss rapid test results, document testing and link HIV-infected patients to follow-up care. Training was integrated into centers’ pre-existing meeting schedules where possible. The NACHC trainer provided intensive on-site technical assistance during start-up, with ongoing support provided via email, telephone and periodic follow-up visits. Patient education materials were also developed in English and Spanish using health literacy principles.4
A more detailed description of the model including the barriers and facilitators experienced during implementation of this project is available elsewhere.5
Data used to determine HIV Tests Offered and Inclusion and Exclusion Criteria for the Study To help understand the results of the project, we used two data sets reflecting application of new procedures. First, we used administrative data reported by all centers through a uniform data system. From this dataset, we obtained the aggregate number of patients seen during the study period. We compared these figures to the number of patients to whom tests were offered, determined from the second data set: de-identified patient-level documentation of tests provided by clinics, which used a standard form developed for this project. We stratified by health center to measure variation across them. We included patients in this analysis if their age was inside the range for which testing guidelines are established.
HIV Tests Performed Patient-level data was used to determine the number of tests offered and performed by each health center during the study period. To measure changes in the percent of patients tested before and after procedures were implemented, health centers provided the total number of patients seen and tests performed in the year prior to the study (2006). We compared this to tests offered during the study period, calculated from the patient-level data set.
Identification of New HIV Cases and Linkage to Care We also used patient-level data to determine test outcomes (negative or preliminary positive) and whether reactive tests were confirmed with western blots. In cases of confirmed infection, we asked health centers to indicate if patients were successfully linked to HIV care.
Characteristics of Patients Offered HIV Screening To determine if there were differences in characteristics of all patients seen and those offered HIV screening, we combined the patient-level testing documentation into categories matching the pre-aggregated administrative dataset and compared the two. Categories of comparison include patient data by age and gender, race/ethnicity and insurance status. We used unadjusted odds ratios and 95% confidence intervals to measure significant differences across categories.
Characteristics of Patients Tested To determine if there were differences in characteristics of patients offered and receiving tests, we used the patient-level data to perform univariable and multivariable logistic regression. We observed different relationships between an overall model to assess differences in testing and separate models for women and men. Therefore, we assessed differences in testing by categories of age, race/ethnicity and insurance status variables, controlling for the health center in which a patient was seen, among women and among men.