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. 2019 Apr 24;19:86. doi: 10.1186/s12874-019-0731-y

Table 1.

Research questions investigated and description of applied missingness models and prior structures for δik

Analysis MOD model Determination of δik What is compared?
Structure Structural assumption Scenario Prior specification
A1 pattern-mixture identical intervention-specific MAR on average δik=δtik, δtik~N01 MAR on average is compared with extreme scenarios (on average). Intervention 1 is the reference of the network.
MME on average δik=δtik, δtik~Nln21
MMNE on average δik=δtik, δtik~Nln21
BC on average δik=δtik, δtik~Nln21,  tik ≠ 1
δik=δtik, δtik~Nln21,  tik = 1
WC on average δik=δtik, δtik~Nln21,  tik ≠ 1
δik=δtik, δtik~Nln21,  tik = 1
A2 pattern-mixture identical intervention-specific MAR fixed δik=δtik, δtik=0 ‘On average’ scenarios are compared with corresponding ‘fixed’ scenarios. Intervention 1 is the reference of the network.
MME fixed δik=δtik, δtik=ln2
MMNE fixed δik=δtik, δtik=ln2
BC fixed δik=δtik, δtik=ln2,  tik ≠ 1
δik=δtik, δtik=ln2,  tik = 1
WC fixed δik=δtik, δtik=ln2,  tik ≠ 1
δik=δtik, δtik=ln2,  tik = 1
B1 pattern-mixture identical common-within-network MAR on average δik = δ, δ~N(0, 1) Identical is compared with hierarchical for each structural assumption.
trial-specific δik = δi, δi~N(0, 1)
intervention-specific δik=δtik, δtik~N01
hierarchical common-within-network MAR on average δik~N(Δ, σ2), Δ~N(0, 1), σ~U(0, 1)
trial-specific δik~NΔiσi2, Δi~N(0, 1), σi~U(0, 1)
intervention-specific δik~NΔtikσtik2, Δtik~N01, σtik~U01
B2a pattern-mixture identical as in analysis B1 MAR on average as in analysis B1 Structural assumptions are compared with each other.
B2b pattern-mixture hierarchical as in analysis B1 MAR on average as in analysis B1 Structural assumptions are compared with each other.
B3 pattern-mixture identical intervention-specific MAR on average δik=δtik, δtik~N01 Pattern-mixture model is compared with selection model for each structural assumption.
selection
C1 pattern-mixture identical intervention-specific MAR on average δik=δtik, δtik~N01 – moderate
δik=δtik, δtik~N0,0.25 – liberal
δik=δtik, δtik~N04 – conservative
Moderate prior variance for δik is compared with liberal and conservative prior variance.

Abbreviations: BC Best-case scenario, MAR Missing at random, MME More missing cases are events, MMNE More missing cases are non-events, MOD Missing outcome data, WC, worst-case scenario