Figure 7.

Add-one and minus-one patterns for a starting adjustment-variable set of {C1, C2} based on DAG in Figure1, taking the associations in the DAG in Figure6as the unknown best working DAG. Note that the variables listed as C2 and C3 are actually these variables measured with error, i.e. C2* and C3* in Figure 6. The solid horizontal line is the RD estimate adjusted on the putative minimally sufficient set {C1}. The dashed horizontal lines are the pre-defined meaningful change thresholds in the RD estimate. The add-one section shows the RD upon adding each variable listed to the adjustment-variable set in turn. The minus-one section shows the RD upon removing each variable listed from the adjustment-variable set in turn.

Evans et al. BMC Medical Research Methodology 2012 12:156   doi:10.1186/1471-2288-12-156
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