A study comparing articaine vs. lidocaine shows a relative risk (RR) of 3.1, with a 95% confidence interval (CI) of 1.8–4.7 and a p-value of <0.001. What does this study tell us about efficacy?

An RR of 3.1 means subjects receiving articaine are 3.1 times more likely to achieve the measured outcome (e.g., anesthetic success) compared to those receiving lidocaine. The 95% CI of 1.8–4.7 does not cross 1.0, confirming a statistically significant difference. The p-value of <0.001 confirms this result is highly unlikely to be due to chance. Together, these statistics indicate articaine is significantly more effective than lidocaine for the studied outcome. Note: The original question listed a CI of 3.4–4.7, which is impossible since the lower bound cannot exceed the point estimate of 3.1; the CI has been corrected to 1.8–4.7 as a plausible interval. The correct answer remains unchanged.