If you typeset a calstable
using the package cals, spanning cells horizontally and vertically centre them, is easy.

\documentclass[british, DIV=12, captions=tableheading]{scrartcl}
\usepackage{cals, url}
\usepackage{babel}
\usepackage{xcolor}
\usepackage[footnotefigures]{MinionPro}
\input{glyphtounicode}
\pdfgentounicode=1
\usepackage[scaled=0.86]{luximono}
\RequirePackage[utf8]{inputenx}
\RequirePackage[T1]{fontenc}
\RequirePackage[letterspace=100,%
babel=true,%
tracking=true,%
kerning=true]%
{microtype}
\renewcommand{\sfdefault}{uop}
\let\nc=\nullcell % Shortcuts
\let\sc=\spancontent
\addtokomafont{caption}{\sffamily\bfseries\small}
\setkomafont{captionlabel}{\normalfont}
\begin{document}
\begin{table*}
\caption{A caption}
\begin{calstable}[c]
% Defining columns relative to each other and relative to the margins
\colwidths{{\dimexpr(\columnwidth)/6\relax}
{\dimexpr(\columnwidth)/5\relax}
{\dimexpr(\columnwidth)/6\relax}
{\dimexpr(\columnwidth)/6\relax}
{\dimexpr(\columnwidth)/6\relax}
}
% The tabular fills the text area if sum of all columns is 5
% Set up the tabular
\makeatletter
\def\cals@framers@width{0.8pt} % Outside frame rules, reduce if the rule is too heavy
\def\cals@framecs@width{0pt}
\def\cals@bodyrs@width{0.6pt}
\cals@setpadding{Ag}
\cals@setcellprevdepth{Al}
\def\cals@cs@width{0pt} % Inside rules, reduce if the rule is too heavy
\def\cals@rs@width{0.6pt}
\def\cals@bgcolor{}
\def\bb{\ifx\cals@borderB\relax % Botton border switch (off-on)
\def\cals@borderB{0pt}
\else \let\cals@borderB\relax\fi}
\def\lp{\ifdim\cals@paddingL=0.0pt\relax % Left padding switch (off-on)
\cals@setpadding{Ag}
\else \setlength{\cals@paddingL}{0pt}\fi}
\def\rp{\ifdim\cals@paddingR=0.0pt\relax % Right padding switch (off-on)
\cals@setpadding{Ag}
\else \setlength{\cals@paddingR}{0pt}\fi}
% R1H1
\thead{\bfseries%
\brow
\lp\cell{}\lp
\cell{}
\cell{}
\alignR\cell{\vfil Statistics}
\rp\alignR\cell{\vfil Std. Error}\rp
\erow
\mdseries%
}
\tfoot{\lastrule\strut}
%R2B1
\brow
\lp\bb\alignL\cell{Difference}\lp
\bb\alignL\cell{Mean}
\cell{}
\alignR\cell{44.200\,00}
\rp\alignR\cell{4.540\,68}\rp\bb
\erow
%R3B2
\brow
\lp\cell{}\lp
\nc{lrt}
\bb\alignL\cell{Lower Bound}
\alignR\cell{33.928\,30}
\rp\cell{}\rp\bb
\erow
%R4B3
\brow
\lp\cell{}\lp
\bb\nc{lrb}\alignL\sc{\vfil 95\% Confidence\\ Interval for Mean}
\alignL\cell{Upper Bound}
\alignR\cell{54.471\,70}
\rp\cell{}\rp
\erow
%R5B4
\brow
\lp\cell{}\lp
\alignL\cell{Kurtosis}
\cell{}
\alignR\cell{-1.000\hspace*{0.9em}}
\rp\alignR\cell{1.334\hspace*{0.9em}}\rp
\erow
\makeatletter
\end{calstable}\par
\end{table*}
\end{document}
biblatex
even though they were about tables and have nothing to to withbiblatex
. (Ironically, one of your questions that was aboutbiblatex
was not tagged withbiblatex
initially.) Appropriate tagging makes it easier for people to find your question and avoids confusions. I'm only mentioning this now since I noticed that this became a pattern and people always had to re-tag your questions that were otherwise tagged quite well.biblatex
. I will take note it next time.biblatex
(ctan.org/pkg/biblatex) is a bibliography and citation package that has usually nothing to do with tables. One sign that this question is not aboutbiblatex
is that your MWE does not load the package at all (there is no\usepackage{biblatex}
or\usepackage[<options>]{biblatex}
).booktabs
orbiblatex
the fact that you use the package is more of a necessary condition rather than a sufficient condition to use the tag. In this case I would guess thatbooktabs
is not actually that relevant to the problem at hand and would not tag the question withbooktabs
, but I may well be wrong. The important tags are certainlymultirow
andtables
and possibly to a lesser extenttabularx
.biblatex
does it is fairly clear from the MWE that it is not involved and hence the tag not helpful. Sincebiblatex
popped up a lot in your question tags (and almost always was not relevant) I thought it would be better to mention it than silently correcting it for all future questions.