background: subjective assessment of primary achalasia is not accurate. we aimed to evaluate surface of barium retention in the objective assessment of these patients. materials and methods: subjective and objective esophageal functions of 99 patients with primary achalasia were evaluated initially and 43 of them were reevaluated one month after balloon dilation. results: predilation: â  9cases...

In most situations the best estimator of a function of the parameter exists, but sometimes it has a complex form and we cannot compute its variance explicitly. Therefore, a lower bound for the variance of an estimator is one of the fundamentals in the estimation theory, because it gives us an idea about the accuracy of an estimator. It is well-known in statistical inference that the Cram&eac...