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For a two-group comparative study, a stratified inference procedure is routinely used to estimate an overall group contrast to increase the precision of the simple two-sample estimator. Unfortunately, most commonly used methods including the Cochran-Mantel-Haenszel statistic for a binary outcome and the stratified Cox procedure for the event time endpoint do not serve this purpose well. In fact, these procedures may be worse than their two-sample counterparts even when the observed treatment allocations are imbalanced across strata. Various procedures beyond the conventional stratified methods have been proposed to increase the precision of estimation when the naive estimator is consistent. In this paper, we are interested in the case when the treatment allocation proportions vary markedly across strata. We study the stochastic properties of the two-sample naive estimator conditional on the ancillary statistics, the observed treatment allocation proportions and/or the stratum sizes, and present a biased-adjusted estimator. This adjusted estimator is asymptotically equivalent to the augmentation estimators proposed under the unconditional setting. Moreover, this consistent estimation procedure is also equivalent to a rather simple procedure, which estimates the mean response of each treatment group first via a stratum-size weighted average and then constructs the group contrast estimate. This simple procedure is flexible and readily applicable to any target patient population by choosing appropriate stratum weights. All the proposals are illustrated with the data from a cardiovascular clinical trial, whose treatment allocations are imbalanced. [ABSTRACT FROM AUTHOR]

: Several studies in Western countries showed that proton-pump inhibitors are superior to histamine2-receptor antagonists or placebo in the treatment of non-erosive gastro-oesophageal reflux disease. The efficacy of acid-suppressive drugs for non-erosive gastro-oesophageal reflux disease in Japan, in which the prevalence ofHelicobacter pyloriinfection is higher compared with Western countries, is unknown.: To compare the efficacy of famotidine and omeprazole in Japanese patients with non-erosive gastro-oesophageal reflux disease by a prospective randomized multicentre trial.: A total of 98 patients received either famotidine 20 mg b.d. (n = 48) or omeprazole once daily (n = 50). Frequency of gastro-oesophageal reflux disease symptoms and health-related quality of life were evaluated at baseline and after 4 weeks of treatment. Complete relief was defined as no gastro-oesophageal reflux disease symptoms during the 7-day interval in week 4.: Complete relief was achieved in 23 (48%) of patients receiving famotidine and 28 (56%) of patients treated with omeprazole. In the famotidine group, complete relief rate inH. pylori-negative patients was significantly lower thanH. pylori-positive patients (35% vs. 64%). Both famotidine and omeprazole improved most scales of health-related quality of life. Omeprazole significantly improved reflux score irrespective ofH. pyloriinfection while famotidine significantly improved reflux score inH. pylori-positive patients but not inH. pylori-negative patients.: Omeprazole is more effective than famotidine for the control of gastro-oesophageal reflux disease symptoms inH. pylori-negative patients, while similar efficacy is observed inH. pylori-positive patients with non-erosive gastro-oesophageal reflux disease. [ABSTRACT FROM AUTHOR]