BACKGROUND A subgroup of clinical trial subjects identified by baseline characteristics is a proper subgroup while a subgroup determined by post randomization events or measures is an improper subgroup. Both types of subgroups are often analyzed in clinical trial papers. Yet, the extensive scrutiny of subgroup analyses has almost exclusively attended to the former. The analysis of improper subg...

In order to determine the occurrence of endometriosis in patients with uterine myoma and in those with polycystic ovarian disease (PCOD) compared to controls, 540 infertile patients were fIrst divided into two age groups of 20-29 and 30-39. Then each group was subdivided to patients with 1) uterine myoma, 2) PCOD, and 3) no uterine myoma or PCOD (control subgroup). The occurrence of endomet...

Results obtained from reliably designed randomized experiments are often considered to be evidence of the highest grade for assessing effectiveness biomedical or behavioral interventions. Nevertheless, even with experiments, statistical bias can arise in post hoc analysis data through adaptive collection. In this article, we discuss need and review some recent developments methodologies address...

When knowledge systems are deployed into a real-world application, then the maintenance and the refinement of the knowledge are essential tasks. Many existing automatic knowledge refinement methods only provide limited control and clarification capabilities during the refinement process. Furthermore, often assumptions about the correctness of the knowledge base and the cases are made. However, ...

Abstract. A subgroup H of a group G is said to be SS-embedded in G if there exists a normal subgroup T of G such that HT is subnormal in G and H T H sG , where H sG is the maximal s- permutable subgroup of G contained in H. We say that a subgroup H is an SS-normal subgroup in G if there exists a normal subgroup T of G such that G = HT and H T H SS , where H SS is an SS-embedded subgroup of ...