Table 1

Data retrieved

CategoryItemsDescription/Observations
Regulatory complianceEthical approvalStudies explicitly reported to be approved by a committee/authority.
Guideline complianceArticles that did not report having experimental protocols ethically approved by an institution or national entity, but reported that some kind of guidelines for use and care of laboratory animals was followed.
Animal modelsGenetic backgroundWhen available.
SexFour options: male, female, both or not reported. For both, information on whether studies were balanced for gender was retrieved.
Number of transgene copiesWhen available.
Experimental designGroup sizeMean group size, based on the available information.
RandomisationStudies explicitly reporting assigning animals to groups randomly.
BlindingStudies explicitly reporting blinding of observers to experimental groups.
Non-transgenic littermate controlStudies explicitly reporting the use of non-transgenic littermates as control.
Splitting littermates into groupsStudies explicitly reporting that littermates were split into groups.
Housing and husbandry conditionsReporting information regarding temperature, humidity, light of the room where animals were kept, and cage size and number of animals per cage.
Animal welfare/proceduresSeverityDescribed in table 2.
RefinementRelevant refinements to minimise suffering and distress, such as housing adaptations.
Euthanasia methodEuthanasia methods were divided into the following categories: ‘Under anaesthesia’ (including anaesthetic overdose), ‘CO2 asphyxiation’, ‘Other’, ‘Not reported’ and ‘Not performed’.
  • A description of the information collected from revised papers is presented for each item

  • CO2, carbon dioxide.