dosresmetaObject {dosresmeta} R Documentation

## dosresmeta Object

### Description

An object returned by dosresmeta function, inheriting from class "dosresmeta", and representing a fitted dose-response (meta-analytical) model.

### Value

Objects of class "dosresmeta" are lists with defined components. Dimensions of such components differs according to the choosen procedure. For the one-stage analysis the dimensions refer to a one dimensional outcome, p predictors and m studies used for fitting the model. For the two-stage analysis the dimensions refer to p outcome parameters, no predictor (only the intercept) and m studies. The following components needs to be included in a legitimate mvmeta object:

 coefficients a p-dimensional vector of the fixed-effects coefficients. vcov estimated p \times p (co)variance matrix of the fixed-effects coefficients. Psi for random-effects models, the estimated p \times p between-study (co)variance matrix. residuals a vector of residuals, that is observed minus fitted values. fitted.values a vector of of fitted mean values. df.residual the residual degrees of freedom. rank the numeric rank of the fitted model. logLik the (restricted) log-likelihood of the fitted model. converged,niter for models with iterative estimation methods, logical scalar indicating if the algorithm eventually converged, and number of iterations. control a list with the values of the control arguments used, as returned by dosresmeta.control. method the estimation method. dim list with the following scalar components: m (number of studies included in estimation, k (number of outcome parameters), p (number of predictors). df list with the following scalar components: nall (number of observations used for estimation, excluding missing values), nobs (equal to nall, minus the number of fixed-effects coefficients in REML models), fixed (number of estimated fixed-effects coefficients), random (number of estimated (co)variance terms). lab list with the following label vectors: p for the p predictors (including intercept). model the model frame used for fitting. call the function call. formula the model supplied. terms the terms object representing the fitted model. proc the estimation procedure. center if the desing matrix had been centered. covariance how the (co)variance had been appproximated. Slist list of approximated (co)variance matrices. id identification vector of the studies. v variances of the outcome values

### Methods

A number of methods functions are available for dosresmeta objects, most of them common to other regression functions. Specifically-written method functions are defined for predict (standard predictions). The qtest method performs the Cochran Q test for heterogeneity only for a two-stage analysis. Other methods have been produced for summary, logLik, coef, and vcov. Printing functions for the objects of classes defined above are also provided. All the methods above are visible (exported from the namespace) and documented. In additions, several default method functions for regression are also applicable to objects of class "mvmeta", such as fitted, residuals, AIC, BIC and update, among others.

### Author(s)

Alessio Crippa, alessio.crippa@ki.se

dosresmeta, dosresmeta-package, mvmetaObject