Critical appraisal:Rex KD, Vemulapalli KC, Rex DK 2015

Risk of bias assessment: cohort study (risk factors)

Bias in selection of participants into study

Selection of the exposed and non-exposed cohorts

Drawn from the same population (low risk)

Bias due to error in exposure measurement

Measurement of exposure

Objective measurements from pre-existing records or <img alt="File:Jutta's info icon.png" src="/australiawiki_test/images/d/d9/Jutta%27s_info_icon.png" width="16" height="16"> baseline (Existing at or before baseline, where baseline is the time at which a participant is recorded to have entered the cohort or, if obtained after baseline, before onset of symptoms of the outcome or any likely effect of the developing outcome on the exposure) physical or biological assessment blind to outcome status (low risk)

Bias due to error in outcome measurement

Measurement of outcome

Outcome measurement unlikely to be influenced by exposure (low risk)

Was outcome of interest absent at the time to which the exposure refers?

Yes (low risk)

Was follow-up long enough for outcome to occur as a consequence of measured exposure? (Requires prior specification of a sufficient follow-up period)

Yes (low risk)

Bias due to non-participation

Participation rate in cohort

Participation rate in exposed cohort ≤10 percentage points different from non-exposed cohort OR exposed and non-exposed are from the same cohort (low risk)

Bias due to missing data

Completeness of follow-up of cohort

Active or passive follow-up of participants with methods for ascertainment of outcome and death clearly described AND with methods for ascertainment of emigration from population-at-risk clearly described or censoring at date of last follow-up OR there is a plausible estimate of >90% follow-up (low risk)

Accuracy of dates of outcome or censoring

Dates of outcome or censoring ascertained to within one year (low risk)

Difference in follow-up between exposed and non-exposed members of cohort

Follow-up methods are the same and likely to achieve the same completeness of follow-up in exposed and non-exposed participants (low risk)

Difference in missing data for exposure between those with or without the outcome

Difference in missing data for exposure < 10 percentage points (low risk)

Bias due to confounding

Comparability of exposed and non-exposed cohorts with respect to potentially important confounding variables (Requires prior specification of potentially important confounders)

Age and other potentially important confounders measured and controlled by design or in analysis (low risk)

Analysis bias

Covariates are appropriately included in statistical analysis models

Variables measuring the same underlying concept or lying in the same causal pathway ARE NOT included together as covariates in statistical analysis models (low risk)

Overall risk of bias

Low risk of bias

Additional comments: Please replace this text and include any additional comments in regards to your risk of bias rating

This appraisal has been completed.

Article

Rex KD, Vemulapalli KC, Rex DK. Recurrence rates after EMR of large sessile serrated polyps. Gastrointest Endosc 2015 Sep;82(3):538-41 Available from: http://www.ncbi.nlm.nih.gov/pubmed/25851161.

Assigned to

User:Victoria.freeman

Topic area

Guidelines:Colorectal cancer/Colonoscopy surveillance

Clinical question

• What is the appropriate colonoscopic surveillance after the removal of large sessile or laterally spreading adenomas?

Form

Form:Quality appraisal cohort risk factors

Outcomes

surveillance

Section below only relevant for Cancer Council Project Officer

Edit appraisal assignment