EDIT: example fixes, answer selected.
I've got a table-within-table setup. The tables are looking fine, but I get two overfull hbox warnings (15.4pt and 25.6pt overfull) per table. I'd like to get rid of these warnings to clean the log, but none of the solutions I found on similar posts are doing the trick for me.
Could someone please help me tweak this table structure to eliminate \hbox warnings?:
\documentclass{article}
\usepackage{multirow}
\newcommand{\minitab}[2][l]{\begin{tabular}{#1}#2\end{tabular}}
\begin{document}
\begin{tabular}{ p{5em} p{29.8em} p{1em} p{5em} }
Q1a1 & Alternative 1: Smartphone & \multirow{7}*{\minitab[l]{1 \\ 0 \\ -66}} & \multirow{7}*{\minitab[l]{Marked \\ Not marked \\ Not applicable}} \\
Q1a2 & Alternative 2: Tablet & \\
Q1a3 & Alternative 3: Laptop & \\
Q1a4 & Alternative 4: Desktop computer & \\
Q1a5 & Alternative 5: Other & \\
Q1dk & Alternative 6: Don't know & \\
Q1ref & Alternative 7: Prefer not to answer & \\
\end{tabular}
\end{document}