. 2021 Jul 16;9(4):100393. doi: 10.1016/j.esxm.2021.100393

Table 3.

Assessment of risk of bias of studies in animal models

Type of bias	Domain	Item	Müller¹⁸ 2008	Kenmoku¹⁹ 2012	Kang²⁰ 2017	Zang²¹ 2018
Selection bias	Sequence generation	Describe the methods used, if any, to generate the allocation sequence in sufficient detail to allow an assessment whether it should produce comparable groups.	Unclear	No	No	Unclear
Selection bias	Sequence generation
Selection bias	Baseline characteristics	Describe all the possible prognostic factors or animal characteristics, if any, that are compared in order to judge whether or not intervention and control groups were similar at the start of the experiment.	Unclear	Yes	Yes	Yes
Selection bias	Baseline characteristics
Selection bias	Allocation concealment	Describe the method used to conceal the allocation sequence in sufficient detail to determine whether intervention allocations could have been foreseen before or during enrolment.	No	No	No	No
Selection bias	Allocation concealment
Performance bias	Random housing	Describe all measures used, if any, to house the animals randomly within the animal room.	No	No	No	Yes
Performance bias	Random housing
Performance bias	Blinding	Describe all measures used, if any, to blind trial caregivers and researchers from knowing which intervention each animal received. Provide any information relating to whether the intended blinding was effective.	No	No	No	No
Performance bias	Blinding
Detection bias	Random outcome assessment	Describe whether or not animals were selected at random for outcome assessment, and which methods to select the animals, if any, were used.	Unclear	No	No	No
Detection bias	Random outcome assessment
Detection bias	Blinding	Describe all measures used, if any, to blind outcome assessors from knowing which intervention each animal received. Provide any information relating to whether the intended blinding was effective.	No	No	No	No
Detection bias	Blinding
Attrition bias	Incomplete outcome data	Describe the completeness of outcome data for each main outcome, including attrition and exclusions from the analysis. State whether attrition and exclusions were reported, the numbers in each intervention group (compared with total randomized animals), reasons for attrition or exclusions, and any re-inclusions in analyses for the review.	Yes	Yes	Yes	Yes
Attrition bias	Incomplete outcome data
Reporting bias	Selective outcome reporting	State how selective outcome reporting was examined and what was found.	Yes	Yes	Yes	Yes
Reporting bias	Selective outcome reporting
Other	Other sources of bias	State any important concerns about bias not covered by other domains in the tool.	Yes	Unclear	Unclear	Yes
Other	Other sources of bias