In a one-sided hypothesis testing problem in clinical trials, the monotonic condition of a tail probability function is fundamentally important to guarantee that the actual type I and II error rates occur at the boundary of their associated parameter spaces. Otherwise, one has to search for the actual rates over the complete parameter space, which could be very computationally intensive. This important property has been extensively studied in traditional one-stage study settings (e.g., non-inferiority or superiority between two binomial proportions), but there is very limited research for this property in a two-stage design setting, e.g., Simon’s two-stage design. In this note, we theoretically prove that the tail probability is an increasing function of the parameter in Simon’s two-stage design. This proof not only provides theoretical justification that p-value occurs at the boundary of the parameter space, but also helps to reduce the computational intensity for study design search.
Objective: To investigate if Cochrane reviews that assess screening interventions address their major harms. Study design and setting: A systematic search for Cochrane reviews that assess screening interventions was performed. Two authors independently screened abstracts, assessed full-texts, and extracted data from included reviews. For each review, two authors judged whether each predefined harm was relevant. When the harm was judged as of questionable relevance, the review was excluded from the denominator in our calculations. Results: Forty-seven reviews were included. Overdiagnosis was addressed in 6 of 39 (15%), overtreatment in 7 of 43 (16%), and psychosocial consequences in 30 of 47 (64%) of reviews where this was judged relevant. When data on harms were included, they were generally not treated with the same methodological rigor as the benefits, with no assessment of the risk of bias or certainty of the evidence. About half of the Abstracts, Plain Language Summaries, and Summary of Findings tables did not include any harms. Conclusion: The underreporting of harms of screening in Cochrane reviews likely reflects primary research and is problematic. We call for broad collaboration to develop reporting guidelines and core outcome sets for studies of screening interventions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.