We have previously demonstrated Stata implementation of bivariate ramdom effects meta-analysis of the sensitivity and specificity of a single binary diagnostic test by means of the midas module (Dwamena NASUG2007; Dwamena WCSUG 2007). In this presentation we extend our work to paired-comparison...

This presentation will demonstrate how to perform diagnostic meta-analysis using user-written macros midas and xtmidas for Stata versions 9 and 10 respectively. Both midas and xtmidas are comprehensive programs of statistical and graphical routines for undertaking meta-analysis of diagnostic...

Methods for meta-analysis of diagnostic test accuracy studies must, in addition to unobserved heterogeneity, account for covariate heterogeneity, threshold effects, methodological quality and small study bias, whic constitute the major threats to the validity of meta-analytic results. These have...

This presentation will demonstrate how to perform diagnostic meta-analysis using midas , a user-written macro. midas is is comprehensive program of statistical and graphical routines for undertaking meta-analysis of diagnostic test performance in Stata. Primary data synthesis is performed within...

The creation and testing of interaction terms in regression models can be very cumbersome, even in Stata 8. We propose a simple wrapping command, -fitint-, that fits any generalised linear model and tests any twoway interactions, as well as all main effects. There is no need to use -xi- because...

Among various structures in Stata for cycling through lists (whether lists of variable names, numbers, or arbitrary strings) are foreach and forvalues, introduced in Stata 7 in 2001, and for, introduced in Stata 3.1 in 1992, and revised in 5.0 (1997) and 6.0 (1999). Typically, each member of the...

I research the market efficiency of the German 6/49 parimutuel lottery game using Stata. To this end, I investigate the existence of profit opportunities for particularly unpopular combinations of numbers (Papachristou and Karamanis (1998)), employing the covariates proposed by Henze and Riedwyl...

A Stata program will be presented for improved quality control of econometric models. It is well known that reported econometric results often have unknown reliability because of selective reporting by the researcher. In particular, t-statistics are often uninformative or misleading when...

Stata's matrix language, Mata, highlighted in Bill Gould's Mata Matters columns in the Stata Journal, is very useful and powerful in its interactive mode. Stata users who write do-files or ado-files should gain an understanding of the Stata-Mata interface: how Mata may be called upon to do one...

Literature on causal inference has emphasized the average causal effect, defined as the mean difference in potential outcomes under different treatment conditions. We consider marginal regression models that describe how causal effects vary in relation to covariates. To estimate parameters, we...