Supplementary Table 1 Risk of bias of each study in detail Random Allocation Concealment Blinding of Blinding of outcome Incomplete outcome data Selective reporting Other bias Sequence (Selection Bias) Participants and assessment (detection (attrition bias) (reporting bias) Generation Personnel bias) (selection bias) (performance bias) Cole et Treatment assignments were See above. Treatment study staff Drop outs reported: Phase After randomization, Power al. in concealed from participants Placebo tablets except for the 1: died (n=34), lost to follow there was limited calculations were (2007)17 blocks of 6. and study staff except for the were identical in pharmacists. No up (n=9). Phase 2: died separate reporting on performed and pharmacists. Placebo tablets appearance to information on how this (n=16), lost to follow up the outcome of the six sufficient sample were identical in appearance folic acid tablets. was done. (n=31). sub-groups. The numbers to folic acid tablets. reasons for these acquired. omissions are thought to be that the author was focusing on the placebo or folic acid group (with our without the two different doses of aspirin) as a whole. Jaszewski Randomization Selected assignment was Unspecified. Unspecified. No consort flow diagram. Recurrent adenomas Inconsistencies et al. was performed made in advance and recorded 139 eligible subjects reported as mean in baseline data (2008)19 using a in sealed envelopes, randomized. 94 completed number rather than provided. No "stratified numbered consecutively. the 3 year 43 relative risk. Data from calculations were randomization dropped out - unrelated paper cannot therefore performed. block". No deaths (n=28), relocation be used in other (n=15). Very high level of information deaths despite excluding for was provided. co-morbidities. Analysis on 49 (intervention) and 45 (control). In drop-out subjects, there was no statistically significant difference in key demographics. Not clear how many were in each group at baseline as numbers in chart incorrect.
Supplementary Table 1 Risk of bias of each study in detail Random Sequence Generation (selection bias) Allocation Concealment (Selection Bias) Blinding of Participants and Personnel (performance bias) Blinding of outcome assessment (detection bias) Incomplete outcome data (attrition bias) Selective reporting (reporting bias) Other bias Cole et al. (2007)17 in blocks of 6. Treatment assignments were concealed from participants and study staff except for the pharmacists. Placebo tablets were identical in appearance to folic acid tablets. See above. Placebo tablets were identical in appearance to folic acid tablets. Treatment study staff except for the pharmacists. No information on how this was done. Drop outs reported: Phase 1: died (n=34), lost to follow up (n=9). Phase 2: died (n=16), lost to follow up (n=31). After randomization, there was limited separate reporting on the outcome of the six sub-groups. The reasons for these omissions are thought to be that the author was focusing on the placebo or folic acid group (with our without the two different doses of aspirin) as a whole. Power calculations were performed and sufficient sample numbers acquired. Jaszewski et al. (2008)19 Randomization was performed using a "stratified randomization block". No other information was provided. Selected assignment was made in advance and recorded in sealed envelopes, numbered consecutively. Unspecified. Unspecified. No consort flow diagram. 139 eligible subjects randomized. 94 completed the 3 year 43 dropped out - unrelated deaths (n=28), relocation (n=15). Very high level of deaths despite excluding for co-morbidities. Analysis on 49 (intervention) and 45 (control). In drop-out subjects, there was no statistically significant difference in key demographics. Not clear how many were in each group at baseline as numbers in chart incorrect. Recurrent adenomas reported as mean number rather than relative risk. Data from paper cannot therefore be used in Inconsistencies in baseline data provided. No calculations were performed.
Paper_systematic_review_diet_int_CRC_survivors_with_amendments_FINAL_CLEAN_VERSION2_incl_tables.docx