4.1.2 For bodies of evidence that include observational research, also systematically assess the following characteristics for each outcome:

  • Dose–response association

  • Plausible confounding that would change the observed effect

  • Strength of association

The following characteristics should be assessed if they are relevant to a particular SR. They are applied more often to evidence from observational studies than to evidence from randomized controlled trials.

  • Dose–response association.

  • Plausible confounding that would decrease an observed effect.

  • Strength of association.

The quality assessment should be guided by the types of study designs included in the SR.

For bodies of evidence that include observational research, assess the following characteristics for each outcome:

  • Dose–response association.

  • Plausible confounding that would decrease an observed effect.

  • Strength of association.

4.1.3 For each outcome specified in the protocol, use consistent language to characterize the level of confidence in the estimates of the effect of an intervention

The quality of evidence receives a single grade: high, moderate, low, or insufficient.

Not mentioned.

The quality of evidence receives a single grade: high, moderate, low, or very low.

4.2 Conduct a qualitative synthesis

All SRs should include a narrative synthesis. Provides guidance (see below).

All SRs should include a narrative synthesis. Provides guidance (see below).

A narrative synthesis should be used where meta-analysis is not feasible or not sensible. Provides guidance on some elements (see below).



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