Quality Filters
General Background and Procedures
In conjunction with the book and journal we aim to alert clinicians to important advances in general medicine by selecting from the biomedical literature those articles whose results are most likely to be both credible and clinically useful.
Quality filters are not to put you off adding new material to these pages, but to make you aware of what procedures have been used in putting this web site together and what the requirements will be for adding to this site in the future.
Therefore, any information available here will always be referenced, allowing you to go back to the original article to decide for yourself whether the information is both valid and relevant to your patient's care. The procedures we follow as we attempt
to achieve this purpose remain much the same as those used in producing the EBM Journal.
Click here to find out the specific procedure for submitting your own evidence. Any information submitted for use in these pages is reviewed by an editorial team, currently consisting of:
The current review team realises its shortcomings in that it is biased towards hospital medicine. There is little that we can do about this, but there is something you can do about it. By sending in evidence from other specialities which can stand up to
these quality filters, you will force us to form review teams in other areas. Hopefully, in this way, the scope and value of this site will be enhanced.
Specific Criteria for Studies of..
..Prevention or Treatment (NNTs)
- random allocation of the participants to the different interventions;
- outcome measures of known or probably clinical importance for at least 80 per cent of participants who entered the investigation;
- an analysis consistent with the study design.
..Diagnosis (Pre-test Probabilities, SpPins + SnNouts, LRs)
- clearly identified comparison groups, at least one of which is free of the target disorder or derangement;
- either an objective diagnostic standard (e.g. machine-produced laboratory result) or a contemporary clinical diagnostic standard (e.g. a venogram for deep vein thrombosis) with demonstrably reproducible criteria for any objectively interpreted compone
nt (e.g. report of better-than-chance agreement among interpreters);
- interpretation of the test without knowledge of the diagnostic standard result;
- interpretation of the diagnostic standard without knowledge of the test result;
- an analysis consistent with the study design.
- for Pre-test Probabilities, also a consecutive series or random sample of patients from a clearly defined setting.
..Prognosis
- an inception cohort of persons, all initially free of the outcome of interest;
- Follow-up of at least 80 per cent of patients until the occurrence of either a major study endpoint or the end of the study;
- an analysis consistent with the study design.
..Causation
- clearly identified comparison group for those at risk for, or having, the outcome of interest (whether from randomised, quasi-randomised or non-randomised controlled trials; cohort-analytic studies with case-by-case matching or statistical adjustment
to create comparable groups; or case-control studies);
- masking of observers of outcomes to exposures (this criterion is assumed to be met if the outcome is objective [e.g. all-cause mortality or an objective test]);
- observers of exposures masked to outcomes for case-control studies and subjects masked to exposure for all other study designs;
- interpretation of the diagnostic standard without knowledge of the test result;
- an analysis consistent with the study design.
..Review Articles
- the clinical topic being reviewed must be clearly stated;
- there must be a description of how the evidence on this topic was tracked down, from what sources and with what inclusion and exclusion criteria;
- at least one article in the review must meet the above criteria for treatment, diagnosis, prognosis or causation.
Click here to submit some evidence.