| Ref ID | 755 |
| First Author | S. Ijaz |
| Journal | JOURNAL OF CLINICAL EPIDEMIOLOGY |
| Year Of Publishing | 2014 |
| URL | https://www.ncbi.nlm.nih.gov/pubmed/24725644 |
| Keywords |
• Cochrane • Observational studies • Risk of bias |
| Problem(s) |
• Weaknesses identified in some Cochrane reviews • Flawed risk of bias undertaken • Inclusion of observational / non-randomised studies |
| Article Type | Empirical |
| Article Subtype | Cross-sectional survey/Methodological systematic review |
| First Author Country | Finland |
| Aim | To assess the justification of inclusion of non-randomised studies from all Cochrane reviews that considered non-randomised studies published between 2000 to 2013. |
| Level of Investigation | Descriptive |
| Summary of Findings | Of the included 202 included Cochrane reviews that considered non-randomised studies published between 2000-2013 most reviews (n=114; 56%) did not justify including non-randomised studies. When they did, most were not in line with Cochrane recommendations. The reasons were divided into two major categories: non-randomised studies were included because randomized controlled trials are wanted (N 5 81, 92%) but not feasible, lacking, or insufficient alone or because RCTs are not needed (N 5 7, 8%). Risk of bias assessment varied across reviews and needs improvement. |
| Number of systematic reviews included | 202 |
| Number of eligible systematic reviews assessed | 508 |
| Treatment impacted | No |
| Treatment impacted description | |
| Interpretation impacted | Not Applicable |
| Interpretation impacted description |