Table 1

Extracted parameters

ParameterPhenotypeArticles
General article information
Conflict of interests statementDeclaration of no conflict of interests8662.8%
Declaration of existing conflict of interests53.6%
No statement about conflict of interests4633.6%
U-87 MG in vitro model
Source of U-87 MG cellsATCC, Manassas, Virginia, USA6648.2%
Chinese Academy of Sciences, Beijing, China2719.7%
Other commercial/institutional sources2417.5%
Colleagues118.0%
Not reported96.6%
U-87 MG cell line authentication conductedYes1611.7%
No/not reported12188.3%
U-87 MG age (maximum number of cell passage)310.7%
710.7%
810.7%
1032.2%
1542.9%
2021.5%
3510.7%
10010.7%
Not reported12389.8%
U-87 MG culture conditions
Glucose level of cell culture mediumLow glucose (1000 mg/dL)32.2%
High glucose (4500 mg/dL)2416.8%
Low and high glucose (in different experiments)10.7%
Without glucose10.7%
Not reported10878.8%
Mycoplasma contamination checkedYes85.8%
Not reported12994.2%
Supplemented antibioticsPenicillin and streptomycin9267.2%
Other antibiotics53.6%
No antibiotics supplemented32.2%
Not reported3727.0%
Source of FBSThermo Fisher Scientific, Waltham, Massachusetts, USA (including Gibco, Invitrogen and Life Technologies)5137.2%
Hyclone Laboratories, Logan, Utah, USA139.5%
Sigma-Aldrich, St Louis, Missouri, USA85.8%
Other sources2216.1%
FBS was not used10.7%
Not reported4230.7%
Control group and outcome measurement
Type of untreated controlDrug vehicle (DMSO)3727.0%
Cell culture medium only139.5%
Not reported8763.5%
Cell viability assessment methodMTT assay, colorimetric6748.9%
CCK8, colorimetric2014.6%
SRB assay, colorimetric96.6%
Alamar Blue assay, colorimetric75.1%
Trypan Blue Exclusion test, cell counting64.4%
WST-1 assay, colorimetric64.4%
MTS assay, colorimetric32.2%
Other assessment methods118.0%
More than one assay used85.8%
  • Extracted parameter phenotypes (including additional information obtained through contacting the authors). One phenotype per article. The column ‘Articles’ shows the absolute and relative frequencies of articles with the parameter phenotype in relation to all 137 included articles.

  • ATCC, American Type Culture Collection; CCK8, Cell Counting Kit-8; DMEM, Dulbecco’s Modified Eagle’s Medium; DMSO, dimethyl sulfoxide; FBS, fetal bovine serum; U-87 MG, Uppsala-87 Malignant Glioma; MTS, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; SRB, Sulforhodamine B; WST-1, water soluble tetrazolium 1.