A statistical tool determines a range within which the difference between two population proportions likely falls. For instance, if a study compares the effectiveness of two different medications, this tool helps estimate the true difference in success rates between the two treatments, accounting for natural variation. This range, expressed as a percentage, provides a level of certainty, such as 95%, that the true difference lies within the calculated boundaries.
This method is crucial for evidence-based decision-making in various fields, including medicine, marketing, and social sciences. It allows researchers to move beyond simply observing sample differences and quantify the uncertainty inherent in extrapolating those differences to larger populations. Historically, the development of such methods marked a significant advance in statistical inference, providing a more nuanced and rigorous approach to comparing groups and drawing conclusions from data.