The Certification Study Guide (6th edition) outlines a structured approach to outbreak investigation, emphasizing that the first step is to verify the problem and establish baseline facts before initiating control measures. When an infection preventionist becomes aware of potential clustering—such as multiple newborn readmissions with staphylococcal infections—the initial priority is to review the medical records of the affected cases.

Reviewing records allows the IP to confirm diagnoses, identify common organisms, determine timing of symptom onset, and assess potential epidemiologic links (e.g., same nursery, staff exposure, procedures, or length of stay). This step helps determine whether the cases represent a true outbreak, coincidental community-acquired infections, or unrelated events. The study guide stresses that interventions should not begin until the problem is clearly defined, as premature actions may waste resources or obscure the true source.

The other options are appropriate later steps in an investigation. Observing practices and obtaining surveillance cultures are targeted control measures that should follow confirmation of an outbreak and hypothesis generation. Beginning prospective surveillance is also important, but only after case definitions and baseline data are established.

CIC exam questions frequently test sequencing of outbreak investigation steps. Recognizing that case confirmation and record review come first is essential for effective infection prevention decision-making and accurate epidemiologic analysis.