Conducting a Survey to Estimate the Compliance of Laboratory Reporting on CD4 T-Cell Testing in Los Angeles County (LAC), 2010

BACKGROUND: In California, HIV laboratory test reporting started in July 2002 and included only confirmatory antibody tests for HIV and other tests indicative of HIV infection, such as viral load results. In 2008, California law was changed to require clinical laboratories to report all CD4+ T-cell tests to the local health officer. The goals of this study are to: 1) estimate the compliance of laboratories with the CD4 reporting law and 2) identify possible reasons for failure to report CD4+ results in Los Angeles County. 

METHODS: In August 2010, we surveyed 708 laboratories identified from the California list of CLIA licensed laboratories. Non-responding laboratories were followed up via phone. Among those surveyed, 204 were excluded from the analysis due to un-deliverable mail (n=84, 41%); laboratory closure (n=60, 29%); disconnected or wrong phone number (n=45, 22%) or duplicates of other laboratories already included in the survey (n=15, 7%). Additionally, 304 laboratories that had a valid address and phone number, but who did not answer any of the questions on the survey were excluded. Of the 200 laboratories that responded to our survey, 69 laboratories were excluded since they either were non-CD4 related laboratories/facilities (e.g. pathology lab or commercial lab) or they responded that they neither performed nor sent out CD4+ T-cell test results. The remaining 131 laboratories were included for analysis. Simple descriptive statistics were performed.

RESULTS:  Thirty-five percent (n=51) of the laboratories surveyed answered that they reported CD4+ T-cell test results, while 80 (61%) reported they did not. Among 71 laboratories that provided reasons not reporting, 63 (89%) laboratories said that they sent their specimens to reference laboratories and expected reference laboratory to report the results for them, 5 (7%) reported rarely receiving requests for CD4+ T-cell testing, 2 (3%) said they were not aware of HIV reporting law and 1 (1%) was aware of law but had not been reporting. Among 80 non-reporting labs, 63 laboratories reported having an average volume of < 10 per week, 5 had 11-50 per week, 1 had 50-100 per week, and 11 did not respond to this question. Since the conclusion of the study, all but one small laboratory have been reporting CD4+ T-cell tests.

CONCLUSIONS: Most non-reporting laboratories we surveyed indicated reliance on reference laboratories for reporting CD4. A survey among the reporting laboratories can help identify and correct the problems of under-reporting of CD4+ T-cell and other HIV-related tests.