College of Medical Laboratory, Dalian Medical University, Dalian, 116044, China.
BMC Med Res Methodol. 2023 Apr 15;23(1):93. doi: 10.1186/s12874-023-01919-3.
To determine the effect size of observed factors considering trigger factors based on parallel-serial models and to explore how multiple factors can be related to the result of complex events for low-probability events with binary outcomes.
A low-probability event with a true binary outcome can be explained by a trigger factor. The models were based on the parallel-serial connection of switches; causal factors, including trigger factors, were simplified as switches. Effect size values of an observed factor for an outcome were calculated as SAR = (Pe-Pn)/(Pe + Pn), where Pe and Pn represent percentages in the exposed and nonexposed groups, respectively, and SAR represents standardized absolute risk. The influence of trigger factors is eliminated by SAR. Actual data were collected to obtain a deeper understanding of the system.
SAR values of < 0.25, 0.25-0.50, and > 0.50 indicate low, medium, and high effect sizes, respectively. The system of data visualization based on the parallel-serial connection model revealed that at least 7 predictors with SAR > 0.50, including a trigger factor, were needed to predict schizophrenia. The SAR of the HLADQB1*03 gene was 0.22 for schizophrenia.
It is likely that the trigger factors and observed factors had a cumulative effect, as indicated by the parallel-serial connection model for binary outcomes. SAR may allow better evaluation of the effect size of a factor in complex events by eliminating the influence of trigger factors. The efficiency and efficacy of observational research could be increased if we are able to clarify how multiple factors can be related to a result in a pragmatic manner.
基于平行-串行模型，根据触发因素确定观察因素的效应大小，并探索对于二分类结果的低概率事件，多个因素如何与复杂事件的结果相关。
具有真实二分类结果的低概率事件可以由触发因素来解释。模型基于开关的平行-串行连接；因果因素，包括触发因素，简化为开关。观察因素对结果的效应大小值计算为 SAR=（Pe-Pn）/（Pe+Pn），其中 Pe 和 Pn 分别代表暴露组和非暴露组的百分比，SAR 代表标准化绝对风险。SAR 消除了触发因素的影响。实际数据的收集有助于更深入地了解系统。
SAR 值<0.25、0.25-0.50 和>0.50 分别表示低、中、高效应大小。基于平行-串行连接模型的数据可视化系统表明，需要至少 7 个 SAR>0.50 的预测因子，包括一个触发因素，才能预测精神分裂症。HLADQB1*03 基因对精神分裂症的 SAR 为 0.22。
平行-串行连接模型表明，触发因素和观察因素可能具有累积效应。SAR 通过消除触发因素的影响，可能允许更好地评估复杂事件中因素的效应大小。如果我们能够以务实的方式阐明多个因素如何与结果相关，那么观察性研究的效率和效果可能会提高。
