\subsection{Questionnaire}
\label{questions}

\begin{subfigs}{results_questions}{Boxplots of the questionnaire results for each visual hand rendering. }[
    Pairwise Wilcoxon signed-rank tests with Holm-Bonferroni adjustment: ** is \pinf{0.01} and * is \pinf{0.05}.
    Lower is better for \textbf{(a)} difficulty and \textbf{(b)} fatigue.
    Higher is better for \textbf{(c)} precision, \textbf{(d)} efficiency, and \textbf{(e)} rating.
  ]
  \subfig[0.19]{results/Question-Difficulty}
  \subfig[0.19]{results/Question-Fatigue}
  \subfig[0.19]{results/Question-Precision}
  \subfig[0.19]{results/Question-Efficiency}
  \subfig[0.19]{results/Question-Rating}
\end{subfigs}

\figref{results_questions} presents the questionnaire results for each visual hand rendering.
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Friedman tests indicated that all questions had statistically significant differences (\pinf{0.001}).
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Pairwise Wilcoxon signed-rank tests with Holm-Bonferroni adjustment were then used each question results (\secref{metrics}):

\begin{itemize}
    \item \textit{Difficulty}: Occlusion was considered more difficult than Contour (\p{0.02}), Skeleton (\p{0.01}), and Mesh (\p{0.03}).
    \item \textit{Fatigue}: None was found more fatiguing than Mesh (\p{0.04}); And Occlusion more than Skeleton (\p{0.02}) and Mesh (\p{0.02}).
    \item \textit{Precision}: None was considered less precise than Skeleton (\p{0.02}) and Mesh (\p{0.02}); And Occlusion more than Contour (\p{0.02}), Skeleton (\p{0.006}), and Mesh (\p{0.02}).
    \item \textit{Efficiency}: Occlusion was found less efficient than Contour (\p{0.01}), Skeleton (\p{0.02}), and Mesh (\p{0.02}).
    \item \textit{{Rating}}: Occlusion was rated lower than Contour (\p{0.02}) and Skeleton (\p{0.03}).
\end{itemize}

In summary, Occlusion was worse than Skeleton for all questions, and worse than Contour and Mesh on 5 over 6 questions.
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Results of Difficulty, Performance, and Precision questions are consistent in that way.
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Moreover, having no visible visual hand rendering was felt by users fatiguing and less precise than having one.
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Surprisingly, no clear consensus was found on Rating.
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Each visual hand rendering, except for Occlusion, had simultaneously received the minimum and maximum possible notes.
