1) assessment of the distribution of patient characteristics and prognostic factors between groups | |
   present | distribution of patient characteristics and prognostic factors assessed without asymmetry between groups |
   absent | not mentioned; distribution of patient characteristics and prognostic factors assessed with asymmetry noted between groups |
2) prevention of the movement of patients between groups after allocation, and the use of intention-to-treat analysis | |
   present | use of intention-to-treat analysis; no movement of patients between groups confirmed |
   absent | not mentioned; patients known to change groups before analysis |
3) the blinding of the patients to the treatment they received | |
   present | statements of double-blind present; use of a placebo; statements of the treatments being indistinguishable present; patients not aware of study due to clinical condition |
   absent | not mentioned; lack of placebo use in control group; readily-distinguishable treatments; blinding breakdown confirmed |
4) the blinding of the health care providers to the treatments received by the patients | |
   present | third-party dispensation of treatments; statements of health care provider blinding present; health care provider identical to outcome observer, and outcome observer is blinded |
   absent | not mentioned; health care team aware of patient allocation; lack of placebo in control condition; readily-distinguishable treatments; blinding breakdown confirmed |
5) the blinding of the outcome observer to the treatment received by the patient | |
   present | statements of double blind present; objective outcome; use of standardized tests or questionnaires that do not require an outcome observer; subjective principle outcome but outcome observer blinded to treatment; blinded health care providers performing outcome assessment |
   absent | not mentioned; subjective outcome without blinding of the outcome observer; blinding breakdown confirmed |
6) completeness of follow-up | |
   present | no patients lost to follow-up; acute experimental design does not permit loss of patients; analysis of lost patients provided according to randomization groups, with reason for loss |
   absent | not mentioned; no analysis of lost patients provided; effect of patient loss to follow-up confirmed |
7) allocation concealment | |
   present | use of consecutive opaque envelopes or pre-ordered treatments; third party assignment of allocation |
   absent | not mentioned; repeatable pattern of allocation; use of obvious identifiers for allocation (e.g., birth date, record number); assignment of treatment by treating physician |