| Author, Year | Did the Study Attempt to Enroll all (or a Random Sample of) Patients Meeting Inclusion Criteria, or a Random Sample (Inception Cohort)? | Were the Groups Comparable at Baseline on key Prognostic Factors (e.g., by Restriction or Matching)? | Did the Study use Accurate Methods for Ascertaining Exposures, Potential Confounders, and Outcomes? | Were Outcome Assessors and/or Data Analysts Blinded to Treatment? | Did the Article Report Attrition? | Did the Study Perform Appropriate Statistical Analyses on Potential Confounders? | Is There Important Differential Loss to Followup or Overall High Loss to Followup? | Were Outcomes Prespecified and Defined, and Ascertained Using Accurate Methods? | Quality Rating |
|---|---|---|---|---|---|---|---|---|---|
| Cunnington, 2008148 | Yes | No | Yes | Unclear | Unclear | Yes | Unclear | Yes | Fair |
| Fosbol, 2009149 | Yes | No | Unclear | Unclear | Unclear | Yes | Unclear | Yes | Fair |
| Gislason, 2009160 | Yes | No | Yes | Unclear | Yes | Yes | No | Yes | Fair |
| Hudson, 2005161 | Yes | Yes | Yes | Unclear | No | Yes | Unclear | Yes | Fair |
| Ko, 2002257 | Yes | No | Yes | Yes | No | Yes | Unclear | Yes | Fair |
| Kurth, 2003260 | No | Yes | Yes | Yes | Yes | Yes | Unclear | Yes | Fair |
| Mamdani, 2002106 | Yes | No | Yes | Unclear | No | Yes | Unclear | Yes | Fair |
| Mamdani, 2003140 | Yes | Yes | Yes | Unclear | No | Yes | Unclear | Yes | Fair |
| Mamdani, 2004162 | Yes | Yes | Yes | Unclear | No | Yes | Unclear | Yes | Fair |
| Mann, 2004109 | No | N/A | Yes | Unclear | No | No | Unclear | Yes | Fair |
| Mellemkjar, 2002107 | Yes | Unclear | Yes | Unclear | Yes | Unclear | Unclear | Yes | Fair |
| Patel, 2004259 | No | No | Yes | Yes | No | Yes | Unclear | Yes | Fair |
| Rahme & Nedjar, 2007108 Rheumatology | Yes | No | Yes | Unclear | No | Unclear | Unclear | Yes | Fair |
| Rahme, 2007 Arthritis and Rheumatism130 | Yes | No | Yes | Yes | No | Yes | Unclear | Yes | Fair |
| Rahme, 2007130 Pharmacoepidemiology and Drug Safety | Yes | No | Yes | Unclear | No | Unclear | Unclear | Yes | Fair |
| Ray, 2007297 | Yes | No | Yes | Unclear | No | Yes | Unclear | Yes | Fair |
| Ray, 2002142 | Yes | Yes | Yes | Unclear | No | Yes | Unclear | Yes | Fair |
| Solomon, 2008114 | Yes | Yes | Yes | Unclear | No | Yes | Unclear | Yes | Fair |
| Solomon 2010114 | Yes | Yes | Yes | Yes | Yes | Yes | No | Yes | Fair |
| Velentgas, 2006146 | Yes | Yes | Yes | Yes | No | No | Unclear | Yes | Fair |
From: Appendix G, Quality Assessment of Trials, Systematic Reviews, and Observational Studies*
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