A pharmaceutical company conducts a 3-year, randomized, double-blind, placebo-controlled trial to evaluate the efficacy of a novel medication in preventing the progression to end-stage renal disease (ESRD) in patients with type 2 diabetes and chronic kidney disease. A total of 3,000 patients are enrolled and randomly assigned in a 1:1 ratio to receive either the novel medication or a placebo. All patients complete the 3-year follow-up period. The study results are summarized in the following table:
| Group | Developed ESRD | Did Not Develop ESRD | Total |
|---|---|---|---|
| Novel medication | 120 | 1380 | 1500 |
| Placebo | 180 | 1320 | 1500 |
Based on the information provided, how many patients must be treated with the novel medication for 3 years to prevent one additional case of end-stage renal disease compared to placebo?
Answer: 25 patients
Answer
25 patients
The Number Needed to Treat (NNT) is defined as the number of patients who need to receive a specific intervention instead of the alternative to prevent one additional adverse outcome. It is calculated as the inverse of the Absolute Risk Reduction (ARR). First, calculate the risk of the event in the control group: . Next, calculate the risk in the treatment group: . The ARR is the difference between these two risks: . Finally, the NNT is , which equals . Therefore, 25 patients need to be treated with the novel medication for 3 years to prevent one additional case of ESRD.
Step-by-Step Solution
Key Concept
The Number Needed to Treat (NNT) is calculated as the inverse of the Absolute Risk Reduction (ARR).