Table 2. Parameters used to simulate datasets.
Simulation Parameters | |
Mean Model | |
Intercept (β0) = 14.00 units | |
Intervention effect (∂) = 2 OR -2 units | |
Linear time trend (τ) = 0.25 units per month | |
Intervention additional time trend (ψ) = 0.15 OR 0.25 OR -0.50 units per month | |
Non-linear calendar time trend {for scenarios D5, D6, D25-D30} | |
such that κ1 ∈ (0, 0.52, 1.00, 1.41, 1.73, 1.98, 2.00, 1.93, 1.73, 1.41, 1.00, 0.52, 0) | |
Non-linear calendar time trend {for scenarios D7, D8, D31-D36} | |
such that κ2 ∈ (0, 1.00, 1.73, 2.00, 1.73, 1.00, 0, -1.00, -1.73, -2.00, -1.73, -1.00, 0) | |
where t ∈ (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13) | |
Non-linear exposure time trend {for scenarios D25-D30} | |
such that ξ1 ∈ (0, 0, 0.26, 0.50, 0.71, 0.87, 0.97, 1.00, 0.97, 0.87, 0.71, 0.50, 0.26) | |
Non-linear exposure time trend {for scenarios D31-D36} | |
such that ξ2 ∈ (0, 0, 0.50, 0.87, 1.00, 0.87, 0.50, 0, -0.50, -0.87, -1.00, -0.87, -0.50) | |
where d ∈ (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12) | |
Fixed Effects Parameterisations for each Scenario | |
D1, D2: yitk = 14 | D19, D20: yik(t) = 14 + 0.25t + 0.25dtk |
D3, D4: yik(t) = 14 + 0.25t | D21, D22: yik(t) = 14 − 2xtk + 0.25t − 0.50dk |
D5, D6: yitk = 14 + κ1t | D23, D24: yik(t) = 14 + 0.25t − 0.50dtk |
D7, D8: yitk = 14 + κ2t | D25, D26: yitk = 14 + 2xtk + κ1t |
D9, D10: yitk = 14 + 2xtk | D27, D28: yitk = 14 + 2xtk + κ1t + ξ1d |
D11, D12: yik(t) = 14 + 2xtk + 0.25t | D29, D30: yitk = 14 + κ1t + ξ1d |
D13, D14: yik(t) = 14 + 2xtk + 0.25t + 0.15dtk | D31, D32: yitk = 14 + 2xtk + κ2t |
D15, D16: yik(t) = 14 + 0.25t + 0.15dtk | D33, D34: yitk = 14 + 2xtk + κ2t + ξ2d |
D17, D18: yik(t) = 14 + 2xtk + 0.25t + 0.25dtk | D35, D36: yitk = 14 + κ2t + ξ2d |
yitk is the HoNOS score for participant i at time step t in cluster k, xtk is an indicator variable for whether at time step t cluster k was under the control or intervention condition, t is the calendar time, dtk is the exposure time to the intervention in cluster k at calendar time t, κ1 and κ2 are sets of parameters corresponding to the non-linear calendar time coefficients, ξ1 and ξ2 are sets of model parameters for the effects of different non-linear exposure times d to the intervention.