Evaluation and Reporting

Evaluating CDR activities can help health departments assess whether their actions have improved HIV prevention and treatment services. Reporting CDR activities and outcomes allows CDC to understand how health departments are implementing CDR.

Health department evaluation of CDR

Evaluation can help health departments assess processes and outcomes of CDR, highlight lessons learned, and identify opportunities for improvement. Health departments can also evaluate the effects of a response on system-level factors, including stigma, social determinants of health, and service gaps.

Evaluation of routine processes, such as cluster detection and community engagement, can occur regularly. This evaluation can include assessing whether activities were conducted as planned and identifying opportunities for improvement.

Evaluation of investigation and response outcomes will vary in scale and type depending on the activities implemented, so should be tailored for different responses. Evaluation of response activities can help answer:

  • What changed as a result of the response activities?
  • Which activities were or were not successful?
  • What could we do better in the future?

With any approach, first consider the metrics and goals determined during the investigation and response. Evaluation questions can include:

  • To what extent were new HIV diagnoses in the cluster identified through CDR activities?
  • Which of the pre-determined response goals were accomplished?
  • To what extent were additional services implemented or expanded?
  • To what extent were policy changes put in place to address barriers and strengthen services?

Once you have described the outcomes of the investigation and response, you can then explore the reasons behind them:

  • What key factors led to success in reaching the response goals?
  • What key challenges prevented certain goals from being met?

Finally, evaluation findings should inform responses to future clusters. Consider how to apply the lessons learned from your evaluation:

  • What would we change when responding to future clusters and outbreaks?
  • What changes could we make to routine prevention, care, and treatment programs to prevent future clusters or outbreaks?

Reporting CDR activities

Reporting CDR activities to CDC is essential for national CDR evaluation. Health departments should report cluster investigation and response activities to CDC by submitting cluster report forms (CRFs) quarterly. CDC uses this information to monitor CDR activities and identify successes and challenges across health departments.

CRFs help CDC understand priority clusters at a national level and assess cluster growth. They also provide information on individual, network, and system-level outcomes. The data reported do not include individual-level information or identifiers.

Components of a CRF include:


Examples of data collected in CRF
Detection methods
  • Cluster detection date and method
  • County of alert (if using time-space or other approaches)
Data reviewed
  • Checklist of additional data sources the health department reviewed
Size of cluster and larger network
  • Number of people in the cluster and larger network
Other characteristics
  • Common venues, or physical and virtual sites
  • Other factors that might be associated with increased HIV transmission
Health outcomes
  • Evidence of recent viral suppression
Outcomes for partners
  • Number of partners tested and their test results
Key findings
  • Narrative summary of key findings describing individual, network, and systems-level activities
  • Level of health department concern for this cluster


Health departments should submit an initial CRF following cluster detection and submit follow-up forms quarterly. Health departments should submit forms yearly for ongoing clusters, and closeout forms when a response ends.

In addition to the information in the CRF, both CDC and health departments use the Enhanced HIV/AIDS Reporting System (eHARS) to evaluate outcomes. eHARS is a secure, browser-based, CDC-developed application that assists health departments with reporting, data management, analysis, and transfer of data to CDC. Health departments should enter cluster IDs into eHARS.

For CRF and eHARS cluster ID submission guidance, please refer to CDC’s HIV Surveillance Branch SharePoint Site. CDC Detection and Response Branch (DRB) epidemiologists can also provide advice and support on evaluation and reporting. Health departments should contact their assigned DRB epidemiologists for further consultation.