|
STUDY DESIGN |
| 1 |
Small sample size• Limits validity and reproducibility |
Larger studies are feasible |
| 2 |
Variable sample type• Fresh vs. archives |
Controversial |
| 3 |
Gold standard• Uncertain standard case definition• Newer tests outperforming old |
Recommend reviewing gold standard according to accuracy, cognisant of different uses for different contexts |
| 4 |
Testing stools vs. purified cultures• Affects specificity |
Stool samples should be used |
| 5 |
Not approximating field conditions• Population descriptors are essential for PPV, NPV |
Population descriptors should be reported for every population studied |
| 6 |
Specificity• Limited data against common gut organisms |
Specificity testing against confounding gut microflora should be considered prior to commercialisation |
|
TEST DESCRIPTORS |
| 7 |
Little data available on stability• Importance of climate variations i.e. temperature, humidity on shelf life and accuracy |
Manufacturers should perform stability studies (real time preferably) |
| 8 |
Reporting of reproducibility• Between different users• As an inherent quality of the tools• Assessment of manufacturing and inter-lot variation |
User reproducibility reported between at least three users and with sufficient number of samples |
|
SCIENTIFIC RIGOR |
| 9 |
Conflation sensitivity with lowest detectable dilution |
Scientific rigor should be a criteria for further inclusion and re-evaluation of test |
