Table 4.
Risk of bias assessment for retained randomized controlled trial articles (Cochrane method).
| Study (first author, year) | Random sequence generation (selection bias) | Allocation concealment (selection bias) | Blinding of participants and personnel (performance bias) | Detection bias | Incomplete outcome data (attrition bias) | Selective reporting bias | Other bias* | |
|---|---|---|---|---|---|---|---|---|
| Participants | Personnel | |||||||
| Abughosh, 2017 [40] | + | ? | ? | − | − | + | + | + |
| Browning, 2014 [38] | ? | ? | ? | − | − | + | + | − |
| Browning, 2016 [33] | + | + | ? | − | − | + | + | − |
| Chapman, 2018 [34] | + | + | ? | − | − | + | + | − |
| Clark, 2004 [41] | + | ? | ? | − | + | ? | − | + |
| Collins, 2019 [37] | + | + | ? | − | + | + | + | − |
| Dale, 2009 [45] | ? | + | − | − | + | + | ? | − |
| Döbler, 2018 [43] | + | + | − | − | ? | ? | + | − |
| Fischer, 2012 [46] | ? | ? | ? | − | − | ? | + | + |
| Hawkins, 2010 [39] | + | + | − | − | ? | + | + | − |
| Hokanson, 2006 [47] | + | ? | ? | − | − | ? | ? | + |
| Huffman, 2021 [42] | ? | ? | ? | − | + | + | + | + |
| Ingersoll, 2015 [48] | ? | ? | ? | − | ? | ? | ? | + |
| Jansink, 2013 [49] | ? | ? | ? | ? | − | ? | ? | − |
| Lauffenburger, 2019 [52] | + | + | − | − | + | + | + | + |
| Safford, 2015 [50] | + | ? | − | − | − | ? | ? | − |
| Swoboda, 2016 [35] | ? | + | + | − | − | + | + | + |
| Swoboda, 2017 [36] | ? | + | + | − | − | ? | + | + |
| Young, 2014 [51] | ? | ? | ? | − | − | ? | ? | − |
| Young, 2019 [44] | + | ? | − | − | + | + | ? | + |
| Young, 2020 [53] | + | ? | + | + | + | + | ? | + |
Abbreviations: + =Low risk of bias, − =High risk of bias, ? = Unclear risk of bias.
Comments (study: comments): (Browning, 2014:Hawthorne effect); (Browning, 2016: Hawthorne effect; contamination due to media coverage of study); (Chapman, 2018: Hawthorne effect); (Collins, 2019: Hawthorne effect); (Dale: additional selection bias imposed by not including patients unlikely to value additional support); (Döbler: social desirability bias based on patients self-report for follow-up outcomes); (Hawkins: sampling bias through convenience sampling); (Jansink: participation bias); (Safford: sampling bias through convenience sampling); (Young, 2014: self-reporting bias).