最近在恶补统计和循证医学(当然都是非常浅的了解性恶补),我终于成功为自己树立了causation≠association的明确概念。设计恰当的试验可以建立causation,而观察性研究只能建立association。Coursera的统计入门课Statistics with R一上来就明确了这个因果关系和相关关系的问题,我也开始反思以前学统计的时候自己到底学了点啥... ...
Everything written above is true enough or, at least, it seemed that way to me. I thought of it as an obvious description of what everybody knows. The change to saying that “association does notnecessarilyimply causation” is important but not that big a deal. It is common sense or lo...
such nonstepping movement is better captured via waveform or raw accelerometry and may provide additional insight into the association between physical activity and clinical diagnoses. Further, this study was observational in nature; therefore, causation should not be inferred. We acknowledge the potential...
Limitations of this study include its observational design. Although sensitivity analyses resulted in similar conclusions, reverse causation bias remains a possibility. Diet information was obtained at the start of the WHS and not at device wear. We only used a single assessment of steps; however, ...
The cross-sectional design can limit the causality relationship, thus reverse causation can’t be ruled out. The UK Biobank study presented a low 5.5% rate of response leading to the involvement of possible participants bias. However, given the large sample size and high internal validity, these...
MR studies also mitigate the problem of reverse causation because the genotype is invariant and not modified by disease.32 MR techniques based on multiple genetic variants selected from across the genome have found a causal role for increased levels of high-density lipoprotein cholesterol, but not ...
studies using a bidirectional MR design are less susceptible to confounding factors and reverse causation. Simultaneously, we implemented a series of measures to fulfill the core assumptions of MR. By applying various MR methods, utilizing the PhenoScanner database, and excluding SNPs associated with ...
mental health problems (Van Ryzin & Dishion,2014; Hayatbakhsh et al.,2007). However, the interactions between substance use and mental health are complex and the causal direction is unclear. Future research investigating the sequence of events is necessary to draw any conclusions about causation....
A potential concern with the present analysis is that life purpose at baseline may have been influenced by the presence of a chronic or life-threatening illness (reverse causation); however, this did not appear to be the case. We conducted sensitivity analyses in which all individuals who died...
Incidence of glioma is approximately 50% higher in males. Previous analyses have examined exposures related to sex hormones in women as potential protective factors for these tumors, with inconsistent results. Previous glioma genome-wide association stud