An integrated tiered service delivery model (ITSDM) based on local CD4 testing demands can improve turn-around times and save costs whilst ensuring accessible and scalable CD4 services across a national programme

PLoS One. 2014 Dec 9;9(12):e114727. doi: 10.1371/journal.pone.0114727. eCollection 2014.


Background: The South African National Health Laboratory Service (NHLS) responded to HIV treatment initiatives with two-tiered CD4 laboratory services in 2004. Increasing programmatic burden, as more patients access anti-retroviral therapy (ART), has demanded extending CD4 services to meet increasing clinical needs. The aim of this study was to review existing services and develop a service-model that integrated laboratory-based and point-of-care testing (POCT), to extend national coverage, improve local turn-around/(TAT) and contain programmatic costs.

Methods: NHLS Corporate Data Warehouse CD4 data, from 60-70 laboratories and 4756 referring health facilities was reviewed for referral laboratory workload, respective referring facility volumes and related TAT, from 2009-2012.

Results: An integrated tiered service delivery model (ITSDM) is proposed. Tier-1/POCT delivers CD4 testing at single health-clinics providing ART in hard-to-reach areas (<5 samples/day). Laboratory-based testing is extended with Tier-2/POC-Hubs (processing ≤ 30-40 CD4 samples/day), consolidating POCT across 8-10 health-clinics with other HIV-related testing and Tier-3/'community' laboratories, serving ≤ 40 health-clinics, processing ≤ 150 samples/day. Existing Tier-4/'regional' laboratories serve ≤ 100 facilities and process <350 samples/day; Tier-5 are high-volume 'metro'/centralized laboratories (>350-1500 tests/day, serving ≥ 200 health-clinics). Tier-6 provides national support for standardisation, harmonization and quality across the organization.

Conclusion: The ITSDM offers improved local TAT by extending CD4 services into rural/remote areas with new Tier-3 or Tier-2/POC-Hub services installed in existing community laboratories, most with developed infrastructure. The advantage of lower laboratory CD4 costs and use of existing infrastructure enables subsidization of delivery of more expensive POC services, into hard-to-reach districts without reasonable access to a local CD4 laboratory. Full ITSDM implementation across 5 service tiers (as opposed to widespread implementation of POC testing to extend service) can facilitate sustainable 'full service coverage' across South Africa, and save>than R125 million in HIV/AIDS programmatic costs. ITSDM hierarchical parental-support also assures laboratory/POC management, equipment maintenance, quality control and on-going training between tiers.

MeSH terms

  • Adult
  • Anti-Retroviral Agents / therapeutic use
  • CD4 Lymphocyte Count*
  • Clinical Laboratory Services*
  • Costs and Cost Analysis*
  • HIV Infections / blood*
  • HIV Infections / drug therapy
  • Health Services Accessibility / economics
  • Humans
  • Point-of-Care Testing
  • Rural Health Services*
  • South Africa
  • Time Factors
  • Workload


  • Anti-Retroviral Agents

Grants and funding

The authors have no support or funding to report.