A healthcare quality professional is conducting a study to determine how many patients contracted influenza...

The study described is evaluating theefficacy of flu shots, specifically how effective they are in preventing influenza among those who received the vaccination.

Definition of Efficacy: Efficacy refers to the ability of an intervention, such as a vaccine, to produce the desired beneficial effect under ideal and controlled circumstances, typically measured in clinical trials.

Measuring Efficacy: In this context, the healthcare quality professional is examining how well the flu shots work in preventing influenza, as indicated by the number of patients who still contracted the flu despite being vaccinated.

Outcome Focus: The study’s focus on the outcome (whether patients contracted the flu) is a direct measure of the vaccine's efficacy, distinguishing it from other metrics like prevalence or process evaluation.