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Generate (population-average) relative treatment effects. If a ML-NMR or meta-regression model was fitted, these are specific to each study population.

Usage

relative_effects(
  x,
  newdata = NULL,
  study = NULL,
  all_contrasts = FALSE,
  trt_ref = NULL,
  probs = c(0.025, 0.25, 0.5, 0.75, 0.975),
  predictive_distribution = FALSE,
  summary = TRUE
)

Arguments

x

A stan_nma object created by nma()

newdata

Only used if a regression model is fitted. A data frame of study details, one row per study, giving the covariate values at which to produce relative effects. Column names must match variables in the regression model. If NULL, relative effects are produced for all studies in the network.

study

Column of newdata which specifies study names, otherwise studies will be labelled by row number.

all_contrasts

Logical, generate estimates for all contrasts (TRUE), or just the "basic" contrasts against the network reference treatment (FALSE)? Default FALSE.

trt_ref

Reference treatment to construct relative effects against, if all_contrasts = FALSE. By default, relative effects will be against the network reference treatment. Coerced to character string.

probs

Numeric vector of quantiles of interest to present in computed summary, default c(0.025, 0.25, 0.5, 0.75, 0.975)

predictive_distribution

Logical, when a random effects model has been fitted, should the predictive distribution for relative effects in a new study be returned? Default FALSE.

summary

Logical, calculate posterior summaries? Default TRUE.

Value

A nma_summary object if summary = TRUE, otherwise a list containing a 3D MCMC array of samples and (for regression models) a data frame of study information.

See also

plot.nma_summary() for plotting the relative effects.

Examples

## Smoking cessation
# \donttest{
# Run smoking RE NMA example if not already available
if (!exists("smk_fit_RE")) example("example_smk_re", run.donttest = TRUE)
# }
# \donttest{
# Produce relative effects
smk_releff_RE <- relative_effects(smk_fit_RE)
smk_releff_RE
#>                           mean   sd  2.5%  25%  50%  75% 97.5% Bulk_ESS
#> d[Group counselling]      1.08 0.42  0.24 0.81 1.08 1.34  1.93     1927
#> d[Individual counselling] 0.83 0.24  0.37 0.67 0.82 0.99  1.34     1173
#> d[Self-help]              0.50 0.40 -0.29 0.24 0.49 0.76  1.32     1990
#>                           Tail_ESS Rhat
#> d[Group counselling]          2122    1
#> d[Individual counselling]     1735    1
#> d[Self-help]                  2528    1
plot(smk_releff_RE, ref_line = 0)


# Relative effects for all pairwise comparisons
relative_effects(smk_fit_RE, all_contrasts = TRUE)
#>                                                  mean   sd  2.5%   25%   50%
#> d[Group counselling vs. No intervention]         1.08 0.42  0.24  0.81  1.08
#> d[Individual counselling vs. No intervention]    0.83 0.24  0.37  0.67  0.82
#> d[Self-help vs. No intervention]                 0.50 0.40 -0.29  0.24  0.49
#> d[Individual counselling vs. Group counselling] -0.25 0.40 -1.03 -0.51 -0.25
#> d[Self-help vs. Group counselling]              -0.58 0.47 -1.48 -0.90 -0.58
#> d[Self-help vs. Individual counselling]         -0.33 0.40 -1.11 -0.58 -0.34
#>                                                   75% 97.5% Bulk_ESS Tail_ESS
#> d[Group counselling vs. No intervention]         1.34  1.93     1927     2122
#> d[Individual counselling vs. No intervention]    0.99  1.34     1173     1735
#> d[Self-help vs. No intervention]                 0.76  1.32     1990     2528
#> d[Individual counselling vs. Group counselling]  0.02  0.54     2698     2503
#> d[Self-help vs. Group counselling]              -0.28  0.38     3019     2749
#> d[Self-help vs. Individual counselling]         -0.07  0.47     2311     2468
#>                                                 Rhat
#> d[Group counselling vs. No intervention]           1
#> d[Individual counselling vs. No intervention]      1
#> d[Self-help vs. No intervention]                   1
#> d[Individual counselling vs. Group counselling]    1
#> d[Self-help vs. Group counselling]                 1
#> d[Self-help vs. Individual counselling]            1

# Relative effects against a different reference treatment
relative_effects(smk_fit_RE, trt_ref = "Self-help")
#>                            mean   sd  2.5%   25%   50%   75% 97.5% Bulk_ESS
#> d[No intervention]        -0.50 0.40 -1.32 -0.76 -0.49 -0.24  0.29     1990
#> d[Group counselling]       0.58 0.47 -0.38  0.28  0.58  0.90  1.48     3019
#> d[Individual counselling]  0.33 0.40 -0.47  0.07  0.34  0.58  1.11     2311
#>                           Tail_ESS Rhat
#> d[No intervention]            2528    1
#> d[Group counselling]          2749    1
#> d[Individual counselling]     2468    1

# Transforming to odds ratios
# We work with the array of relative effects samples
LOR_array <- as.array(smk_releff_RE)
OR_array <- exp(LOR_array)

# mcmc_array objects can be summarised to produce a nma_summary object
smk_OR_RE <- summary(OR_array)

# This can then be printed or plotted
smk_OR_RE
#>                           mean   sd 2.5%  25%  50%  75% 97.5% Bulk_ESS Tail_ESS
#> d[Group counselling]      3.22 1.51 1.27 2.24 2.94 3.82  6.89     1927     2122
#> d[Individual counselling] 2.37 0.61 1.44 1.96 2.28 2.68  3.80     1173     1735
#> d[Self-help]              1.79 0.77 0.75 1.27 1.63 2.14  3.73     1990     2528
#>                           Rhat
#> d[Group counselling]         1
#> d[Individual counselling]    1
#> d[Self-help]                 1
plot(smk_OR_RE, ref_line = 1)

# }

## Plaque psoriasis ML-NMR
# \donttest{
# Run plaque psoriasis ML-NMR example if not already available
if (!exists("pso_fit")) example("example_pso_mlnmr", run.donttest = TRUE)
# }
# \donttest{
# Produce population-adjusted relative effects for all study populations in
# the network
pso_releff <- relative_effects(pso_fit)
pso_releff
#> ---------------------------------------------------------------- Study: FIXTURE ---- 
#> 
#> Covariate values:
#>  durnpso prevsys  bsa weight  psa
#>      1.6    0.62 0.34   8.34 0.14
#> 
#>                     mean   sd 2.5%  25%  50%  75% 97.5% Bulk_ESS Tail_ESS Rhat
#> d[FIXTURE: ETN]     1.66 0.09 1.48 1.60 1.66 1.72  1.83     4513     3345    1
#> d[FIXTURE: IXE_Q2W] 3.03 0.10 2.84 2.96 3.02 3.09  3.22     5525     3008    1
#> d[FIXTURE: IXE_Q4W] 2.61 0.09 2.44 2.55 2.61 2.68  2.80     5577     3082    1
#> d[FIXTURE: SEC_150] 2.22 0.12 1.99 2.14 2.22 2.29  2.45     4577     3514    1
#> d[FIXTURE: SEC_300] 2.52 0.12 2.29 2.44 2.52 2.60  2.76     5349     3031    1
#> 
#> -------------------------------------------------------------- Study: UNCOVER-1 ---- 
#> 
#> Covariate values:
#>  durnpso prevsys  bsa weight  psa
#>        2    0.73 0.28   9.24 0.28
#> 
#>                       mean   sd 2.5%  25%  50%  75% 97.5% Bulk_ESS Tail_ESS
#> d[UNCOVER-1: ETN]     1.51 0.09 1.34 1.45 1.51 1.56  1.68     3949     3556
#> d[UNCOVER-1: IXE_Q2W] 2.92 0.09 2.76 2.86 2.92 2.98  3.10     5578     3398
#> d[UNCOVER-1: IXE_Q4W] 2.51 0.08 2.35 2.45 2.51 2.57  2.67     5584     3028
#> d[UNCOVER-1: SEC_150] 2.11 0.12 1.88 2.03 2.11 2.20  2.36     4648     3485
#> d[UNCOVER-1: SEC_300] 2.42 0.12 2.18 2.33 2.42 2.50  2.66     5052     3333
#>                       Rhat
#> d[UNCOVER-1: ETN]        1
#> d[UNCOVER-1: IXE_Q2W]    1
#> d[UNCOVER-1: IXE_Q4W]    1
#> d[UNCOVER-1: SEC_150]    1
#> d[UNCOVER-1: SEC_300]    1
#> 
#> -------------------------------------------------------------- Study: UNCOVER-2 ---- 
#> 
#> Covariate values:
#>  durnpso prevsys  bsa weight  psa
#>     1.87    0.64 0.27   9.17 0.24
#> 
#>                       mean   sd 2.5%  25%  50%  75% 97.5% Bulk_ESS Tail_ESS
#> d[UNCOVER-2: ETN]     1.51 0.08 1.35 1.45 1.51 1.56  1.67     3931     3260
#> d[UNCOVER-2: IXE_Q2W] 2.92 0.09 2.76 2.86 2.92 2.98  3.10     5489     3424
#> d[UNCOVER-2: IXE_Q4W] 2.51 0.08 2.36 2.45 2.51 2.56  2.67     5465     3262
#> d[UNCOVER-2: SEC_150] 2.11 0.12 1.88 2.03 2.11 2.19  2.35     4745     3537
#> d[UNCOVER-2: SEC_300] 2.42 0.12 2.18 2.34 2.42 2.50  2.66     5133     3189
#>                       Rhat
#> d[UNCOVER-2: ETN]        1
#> d[UNCOVER-2: IXE_Q2W]    1
#> d[UNCOVER-2: IXE_Q4W]    1
#> d[UNCOVER-2: SEC_150]    1
#> d[UNCOVER-2: SEC_300]    1
#> 
#> -------------------------------------------------------------- Study: UNCOVER-3 ---- 
#> 
#> Covariate values:
#>  durnpso prevsys  bsa weight psa
#>     1.78    0.59 0.28   9.01 0.2
#> 
#>                       mean   sd 2.5%  25%  50%  75% 97.5% Bulk_ESS Tail_ESS
#> d[UNCOVER-3: ETN]     1.53 0.08 1.38 1.47 1.53 1.58  1.69     3948     3433
#> d[UNCOVER-3: IXE_Q2W] 2.94 0.09 2.77 2.88 2.94 3.00  3.11     5582     3334
#> d[UNCOVER-3: IXE_Q4W] 2.53 0.08 2.37 2.47 2.53 2.58  2.68     5325     3410
#> d[UNCOVER-3: SEC_150] 2.13 0.12 1.90 2.05 2.13 2.21  2.36     4752     3428
#> d[UNCOVER-3: SEC_300] 2.43 0.12 2.21 2.35 2.43 2.51  2.67     5092     3372
#>                       Rhat
#> d[UNCOVER-3: ETN]        1
#> d[UNCOVER-3: IXE_Q2W]    1
#> d[UNCOVER-3: IXE_Q4W]    1
#> d[UNCOVER-3: SEC_150]    1
#> d[UNCOVER-3: SEC_300]    1
#> 
plot(pso_releff, ref_line = 0)


# Produce population-adjusted relative effects for a different target
# population
new_agd_means <- data.frame(
  bsa = 0.6,
  prevsys = 0.1,
  psa = 0.2,
  weight = 10,
  durnpso = 3)

relative_effects(pso_fit, newdata = new_agd_means)
#> ------------------------------------------------------------------ Study: New 1 ---- 
#> 
#> Covariate values:
#>  durnpso prevsys bsa weight psa
#>        3     0.1 0.6     10 0.2
#> 
#>                   mean   sd 2.5%  25%  50%  75% 97.5% Bulk_ESS Tail_ESS Rhat
#> d[New 1: ETN]     1.25 0.23 0.80 1.10 1.25 1.40  1.71     6553     3024    1
#> d[New 1: IXE_Q2W] 2.88 0.23 2.46 2.73 2.88 3.04  3.34     6972     3082    1
#> d[New 1: IXE_Q4W] 2.47 0.22 2.05 2.32 2.47 2.62  2.91     6962     3203    1
#> d[New 1: SEC_150] 2.08 0.23 1.63 1.92 2.07 2.23  2.53     6516     2947    1
#> d[New 1: SEC_300] 2.38 0.23 1.95 2.22 2.38 2.53  2.83     7079     3406    1
#> 
# }