The article discusses the importance of rigorous methods in equivalence trials, which aim to show that two treatments are therapeutically equivalent. It highlights that these trials are often poorly designed and analyzed, leading to potential biases and incorrect conclusions. The design of equivalence trials should mirror those of comparative trials, with careful attention to patient recruitment, protocol adherence, and analysis methods. Confidence intervals are crucial for determining equivalence, as they provide a range within which the true difference between treatments is likely to lie. The article explains that equivalence trials generally require larger sample sizes than comparative trials and that the handling of withdrawals and protocol deviations must be particularly careful. The paper emphasizes that the concept of equivalence is not absolute and that the true difference between treatments is unlikely to be outside a predefined range. The use of confidence intervals is central to equivalence trials, and the selection of the equivalence range (Δ) is a critical decision that should be based on clinical expertise. The article also discusses the importance of using appropriate statistical methods, such as intention-to-treat and per-protocol analyses, to ensure the validity of the trial results. The paper provides an example of an equivalence trial comparing two asthma inhalers, showing how the 95% confidence interval for the treatment difference falls within the predefined range of equivalence, thus confirming the equivalence of the two treatments. The article concludes that equivalence trials require careful planning, rigorous execution, and appropriate statistical analysis to ensure reliable conclusions. It also stresses the importance of maintaining high standards in the design and conduct of these trials to avoid biases and ensure the validity of the results.The article discusses the importance of rigorous methods in equivalence trials, which aim to show that two treatments are therapeutically equivalent. It highlights that these trials are often poorly designed and analyzed, leading to potential biases and incorrect conclusions. The design of equivalence trials should mirror those of comparative trials, with careful attention to patient recruitment, protocol adherence, and analysis methods. Confidence intervals are crucial for determining equivalence, as they provide a range within which the true difference between treatments is likely to lie. The article explains that equivalence trials generally require larger sample sizes than comparative trials and that the handling of withdrawals and protocol deviations must be particularly careful. The paper emphasizes that the concept of equivalence is not absolute and that the true difference between treatments is unlikely to be outside a predefined range. The use of confidence intervals is central to equivalence trials, and the selection of the equivalence range (Δ) is a critical decision that should be based on clinical expertise. The article also discusses the importance of using appropriate statistical methods, such as intention-to-treat and per-protocol analyses, to ensure the validity of the trial results. The paper provides an example of an equivalence trial comparing two asthma inhalers, showing how the 95% confidence interval for the treatment difference falls within the predefined range of equivalence, thus confirming the equivalence of the two treatments. The article concludes that equivalence trials require careful planning, rigorous execution, and appropriate statistical analysis to ensure reliable conclusions. It also stresses the importance of maintaining high standards in the design and conduct of these trials to avoid biases and ensure the validity of the results.