Table 2:

Results of assessment of the 22 reports for risk of bias*

StudySequence generationAllocation concealmentBlinding§Incomplete outcome dataSelective outcome reporting**
Abete et al.6UnclearUnclearUnclearLowUnclear
Abeysekara et al.36††LowLowHighLowLow
Anderson et al.22UnclearUnclearLowLowUnclear
Anderson et al.17UnclearUnclearLowLowUnclear
Belski et al.23LowLowLowLowLow
Cobiac et al.24UnclearUnclearUnclearLowUnclear
Duane et al.7UnclearUnclearLowLowUnclear
Finley et al.25UnclearUnclearUnclearLowUnclear
Gormley et al.37UnclearUnclearUnclearLowUnclear
Gravel et al.26LowLowLowHighLow
Hermsdorff et al.8UnclearUnclearUnclearLowLow
Hodgson et al.33LowLowLowLowLow
Jenkins et al.35UnclearLowLowLowLow
Jimenez-Cruz et al.34UnclearUnclearUnclearLowUnclear
Mackay et al.27UnclearUnclearLowLowLow
Marinangeli et al.38UnclearUnclearLowLowLow
Pittaway et al.28UnclearUnclearLowLowUnclear
Pittaway et al.29UnclearUnclearLowLowUnclear
Shams et al.30UnclearUnclearUnclearLowUnclear
Winham et al.31LowLowUnclearLowLow
Winham et al.20UnclearUnclearUnclearLowLow
Zhang et al.32UnclearUnclearLowLowUnclear
  • * The Cochrane risk-of-bias tool19 was used to assess the risk of bias for each study. High risk = methodologic flaw in study design was likely to have affected the true outcome, low risk = the effect of the study’s methodologic flaw was deemed inconsequential to the true outcome, unclear risk = insufficient information was given to assess risk.

  • Assessed the randomization method and whether it would produce comparable groups.

  • Assessed whether investigators could tell to which treatment participants were going to be randomly allocated.

  • § Assessed whether investigators and/or participants were aware of group allocation.

  • Assessed whether missing outcome data, including loss to follow-up and exclusion from analysis, may have affected the true outcome.

  • ** Assessed whether investigators pre-registered the trial or specified primary and secondary outcomes, or both.

  • †† The results of this trial may have been influenced by another potential source of bias: participants in the dietary pulse arm were given both food and dietary advice throughout the study, whereas participants in the control arm were simply told to keep following their usual dietary habits.