Create diagram using xymatrix

Question

I'm trying to reproduce the diagram below using xymatrix package:

This is what I've done so far:

\documentclass{article}

\usepackage[all]{xy}

\begin{document}

\xymatrix@C=1cm{
    % First row
    \txt{FASE I\\Planejamento da Revisão} & 
    \txt{FASE II\\Realização da Revisão} &
    \txt{FASE III\\Documentação da Revisão} &
    \\
    % Second row
    *++[F-,]\txt{1. Especificar questões da\\ pesquisa} \ar[d] & 
    *++[F-,]\txt{3. Identificar e selecionar\\ pesquisas} \ar[d] & 
    *++[F-,]\txt{7. Analisar resultados} \ar[d]
    \\
    % Third row
    *++[F-,]\txt{2. Desenvolver protocolo da\\ revisão questões da pesquisa} \ar[ur] &
    *++[F-,]\txt{4. Avaliar a qualidade dos\\ estudos} \ar[d] &
    *++[F-,]\txt{8. Elaborar relatório}
    \\
    % Fourth row
    & *++[F-,]\txt{5. Extrair dados} \ar[d] & 
    \\
    % Fifth row
    & *++[F-,]\txt{6. Sintetizar dados} \ar[uuur] & 
    \\
}

\end{document}

Which gives me this:

How can I reproduce using xymatrix package the arrow between step 2 and 3 and between step 6 and 7, so it turns and doesn't pass through the other steps?

Also, how can I "group" each column in a frame, as it is in the original diagram?

Answer 1

I know you said that you only want xymatrix solutions, but I'm a tikz partisan and I only noticed you said that after I made this.

\documentclass{article}
\usepackage{geometry}
\usepackage{tikz}
\usetikzlibrary{matrix}
\usetikzlibrary{calc}
\usetikzlibrary{fit}

\begin{document}

\begin{tikzpicture}
\matrix (m) [
    matrix of nodes,
    row sep=0.4cm,
    column sep=1cm,
    % Set the size of the text boxes to be 4cm x 15pt
    every node/.style={text width=4cm, text depth=15pt},
    every node/.append code={ 
       % Check whether we're on the top row
       \ifnum\pgfmatrixcurrentrow=1\relax
          % Top row: align  center and don't draw rectangles
          \pgfkeysalso{align=center}
       \else
          % other rows: align left and "draw" the rectangles
          \pgfkeysalso{align=left,draw}
       \fi
    }
]{
% First row
% Need braces in order to use \\ as an explicit linebreak
{FASE I \\ Planejamento da Revisão} &
{FASE II\\ Realização da Revisão} &
{FASE III\\ Documentação da Revisão} \\
% Second row
1. Especificar questões da pesquisa &
3. Identificar e selecionar pesquisas &
7. Analisar resultados\\
% Third row
2. Desenvolver protocolo da revisãoa&
4. Avaliar a qualidade dos estudos&
8. Elaborar relatório\\
% Fourth row
& {5. Extrair dados}  &
\\
% Fifth row
% I need to force tikz to create empty nodes for fitting later
% But we don't want it to make empty rectangles, hence |[draw=none]|
|[draw=none]|& {6. Sintetizar dados} & |[draw=none]| 
\\};

\draw[->] (m-2-1) -- (m-3-1);
% Make the first zigzag path
\draw[->] (m-3-1.south)  -- ++(0,-0.5)
                   -| ($(m-2-2.west) - (0.5,0)$)
                   -- (m-2-2.west);
\draw[->] (m-2-2) -- (m-3-2);
\draw[->] (m-3-2) -- (m-4-2);
\draw[->] (m-4-2) -- (m-5-2);

% Make the second zigzag path
\draw[->] (m-5-2.east)  -- ++(0.5,0)
                   |- (m-2-3.west);

\draw[->] (m-2-3) -- (m-3-3);

% Draw the three "fit" rectangles
\node[rectangle,draw,fit=(m-1-1)(m-5-1)]{}; 
\node[rectangle,draw,fit=(m-1-2)(m-5-2)]{};
\node[rectangle,draw,fit=(m-1-3)(m-5-3)]{};

\end{tikzpicture}
\end{document}  

Answer 2

The best I've been able to get using backticks is

\documentclass{article}

\usepackage[all]{xy}

\begin{document}

\xymatrix{
    % First row
    \txt{FASE I\\Planejamento da Revisão}
    \ar[d]
     & &
    \txt{FASE II\\Realização da Revisão} & &
    \txt{FASE III\\Documentação da Revisão} & &
    \\
    % Second row
    *++[F-,]\txt{1. Especificar questões da\\ pesquisa} \ar[d] & &
    *++[F-,]\txt{3. Identificar e selecionar\\ pesquisas} \ar[d] & &
    *++[F-,]\txt{7. Analisar resultados} \ar[d]
    \\
    % Third row
    *++[F-,]\txt{2. Desenvolver protocolo da\\ revisão questões da pesquisa}
    \ar`d[dr]`[ur]`[urr][urr] % \ar[ur]
     & &
    *++[F-,]\txt{4. Avaliar a qualidade dos\\ estudos} \ar[d] & &
    *++[F-,]\txt{8. Elaborar relatório}
    \\
    % Fourth row
    & & *++[F-,]\txt{5. Extrair dados} \ar[d] & &
    \\
    % Fifth row
    & & *++[F-,]\txt{6. Sintetizar dados}
    \ar`r[ruuu]`[rruuu][rruuu] % \ar[uuur]
    & &
}

\end{document}

I tried to get the frames by adding headless arrows (\ar@{-}) offset from the appropriate matrix entries, but I couldn't figure out the offset syntax. I suppose you could use the "introduce extra columns" trick to have the frame corners at matrix entries, but now you're adding two rows and six columns to the matrix, which starts seeming excessive.