Fig 1.
Mean plots with 95% confidence intervals (C.I.) of the total HoNOS scores plotted against the calendar time (study months) at each CMHT for the OXTEXT-7 study.
Data to the left of the vertical line occurred before the intervention and data to the right after the intervention was introduced.
Fig 2.
Graphical representation of the standard stepped wedge design intervention roll-out.
Fig 3.
Four potential ways that an outcome can change as a function of time.
The dashed line represents when the intervention is introduced. See text for further details. a.) Step change, no time trend, b.) Linear trends in calendar and exposure time, c.) Step change, non-linear trend in calendar time, d.) Step change, linear trends in calendar and exposure time.
Table 1.
Summary of mathematical notation.
Table 2.
Parameters used to simulate datasets.
Fig 4.
The simulated data under scenario D17: yik(t) = 14 + 2xtk + 0.25t + 0.25dtk.
The means and 95% confidence intervals are plotted against the time since the intervention was introduced. Data to the left of the vertical line occurred before the intervention and data to the right after the intervention was introduced.
Table 3.
Model structures for linear mixed effects models fitted to simulated datasets.
Fig 5.
The heat map shows the coverage probability of the intervention effect at six months exposure for the nine fitted models with CS correlation structure.
The heat map was very similar when the AR(1) structure was specified and for the time-averaged intervention effect. Values at the bottom of each column show the average coverage probability for each fitted model and the average width of the confidence interval for the intervention effect. Odd-numbered scenarios are simulated with ρ = -0.5 and even-numbered scenarios have ρ = 0.5.
Fig 6.
Plot of mean bias and mean 95% confidence interval width over all datasets within each scenario for each fitted model for the estimate of the intervention effect at six months exposure.
Fig 7.
Plot of mean bias and mean 95% confidence interval width over all datasets within each scenario for each fitted model for the estimate of the time-averaged intervention effect.
Fig 8.
Plot of the mean of the MSE (mean square error) and mean BIC over all datasets within each scenario for each fitted model and where fitted models have assumed CS correlation structure.
Table 4.
Estimates of the treatment effect after six months exposure time to the intervention for the original OXTEXT-7 SWCRT data.