Critical appraisal:Switzer-Taylor V, Schlup M, Lübcke R, Livingstone V, Schultz M 2008

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Critical Appraisal

Article being appraised

Switzer-Taylor V, Schlup M, Lübcke R, Livingstone V, Schultz M. Barrett's esophagus: a retrospective analysis of 13 years surveillance. J Gastroenterol Hepatol 2008 Sep 1;23(9):1362-7 Abstract available at http://www.ncbi.nlm.nih.gov/pubmed/18205769.


Applicable clinical question

Key Facts

Study Design

cohort study

Number of Patients:

212


Includes an economic evaluation

no

Evidence ratings

Level of evidence

III-3

Risk of bias
High risk of bias Comments: Retrospective analysis of a cohort of patients in a surveillance programme at a single centre in New Zealand. Surveillance timing protocol (in line with contemporaneous guidelines) was suggested but not strictly adhered to on analysis. No information given regarding adherence to biopsy protocols. No follow up of those diagnosed with Barrett's oesophagus but who didn't enter surveillance protocol. Those with initial high grade included in study but diagnosed with cancer in 1-2 months and therefore should of been excluded as incident cases.

Risk of bias assessment: cohort study

Subject selection
"New technology" group
No response
Comparison group
No response
Comparability of groups on demographic characteristics and clinical features
No response
Measurement of outcomes
Outcome measures blind to technology used
No response
Same method of measurement used across comparison groups
No response
Completeness of follow-up
Was follow-up complete and were all patients included in the analysis?
No response
Size of effect
1 Reason for decision: The study found that in those that developed oesophageal adenocarcinoma in the study period, there was a significantly higher proportion with initial ulcer/dysplasia (8.9%) and length of Barrett's (8.89cm) compared to those who didn't develop cancer (initial ulcer or dysplasia -3.9%; length of Barrett's - 5.84cm). However, as outline above, there are significant limitations in the study methodology giving potential for unmeasured confounding and bias
Relevance of evidence
1 Additional comments: Study looks at development of patient relevant outcome (cancer) but as outlined above low quality evidence.
Result of appraisal

Jutta's tick icon.png Included




Completed by

Dr Bradley Kendall MBBS, FRACP


Jutta's tick icon.png This appraisal has been completed.


Article
Switzer-Taylor V, Schlup M, Lübcke R, Livingstone V, Schultz M. Barrett's esophagus: a retrospective analysis of 13 years surveillance. J Gastroenterol Hepatol 2008 Sep 1;23(9):1362-7 Abstract available at http://www.ncbi.nlm.nih.gov/pubmed/18205769.
Assigned to
User:Brad.kendall
Topic area
Guidelines:Barrett's
Clinical question
Form
Form:Critical appraisal


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