Risk Of Bias

Each study in the PTSD-Repository was coded for risk of bias (ROB) in specific domains as well as an overall risk of bias for the study. Detailed information about the specific coding strategy is available in Comparative Effectiveness Review [CER] No. 207, Psychological and Pharmacological Treatments for Adults with Posttraumatic Stress Disorder. (See our "Risk of Bias" data story.)
Most domains were rated as Yes (i.e., minimal risk of bias), No (i.e., high risk of bias) or Unclear (i.e., bias could not be determined). The overall study rating is based on the domains and is coded as low, medium or high risk of bias. The 4 domains that were included as components of the overall rating include: Selection bias--randomization adequate, allocation concealment adequate, groups similar at baseline and whether they used intention to treat analyses; Performance bias--care providers masked and patients masked; Detection bias--outcome assessors masked; Attrition bias--overall attrition less than or equal to 20% vs over 20%; differential attrition less than or equal to 15% vs over 15%.
Additional items assessed (but not considered as part of the overall rating) include: Reporting bias--all prespecified outcomes reported; Reporting bias--method for handling dropouts; Outcome measures equal valid and reliable; Study reports adequate treatment fidelity based on measurements by independent raters.

在 PTSD-Repository 中的每项研究均根据特定领域的偏倚风险（ROB）以及研究的整体偏倚风险进行编码。有关特定编码策略的详细信息，请参阅《比较有效性评估》（Comparative Effectiveness Review，CER）第 207 号：《针对成年创伤后应激障碍患者的心理和药物治疗》。（详见我们的“偏倚风险”数据故事。）大多数领域被评为是（即偏倚风险极低）、否（即偏倚风险高）或不明确（即无法确定偏倚）。整体研究评级基于这些领域，并编码为低、中或高风险偏倚。构成整体评级组成部分的 4 个领域包括：选择偏倚——随机化充分、分配隐藏充分、基线时各组相似以及是否使用意向治疗分析；执行偏倚——医护人员和患者均被屏蔽；检测偏倚——结果评估者被屏蔽；脱落偏倚——总体脱落率不超过 20% 与超过 20% 的情况；差异脱落率不超过 15% 与超过 15% 的情况。此外，还评估了以下项目（但未将其纳入整体评级）：报告偏倚——所有预先指定的结果均得到报告；报告偏倚——处理脱落的方法；结果测量方法有效且可靠；研究报告基于独立评估者的测量，显示了充足的治疗依从性。