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	\begin{pgfonlayer}{nodelayer}
		\node [style=Red Box] (0) at (4, -1.5) {Will Terminate?};
		\node [style=Red Box] (1) at (-4.25, -1.5) {Market Measures};
		\node [style=Red Box] (5) at (-0.25, 2) {Enrollment Status};
		\node [style=emptyBox] (9) at (12.25, 6.25) {Fundamental Efficacy/Safety};
		\node [style=emptyBox] (10) at (-0.25, 8) {Previously Observed Efficacy/Safety};
		\node [style=emptyBox] (12) at (14, 0.25) {Currently Observed Efficacy/Safety};
		\node [style=Gray Box] (18) at (-6.5, 1.5) {Population};
		\node [style=Gray Box] (20) at (-0.25, 5) {Decision to procced with Phase III};
		\node [style=Gray Box] (21) at (0, -3.5) {Condition};
		\node [style=Gray Box] (22) at (7.25, 2.75) {Elapsed Duration};
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		\draw [style=RightArrow] (18) to (1);
		\draw [style=RightArrow] (9) to (10);
		\draw [style=RightArrow] (10) to (20);
		\draw [style=RightArrow] (9) to (12);
		\draw [style=RightArrow] (12) to (0);
		\draw [style=Light Arrow] (21) to (1);
		\draw [style=Light Arrow] (21) to (0);
		\draw [style=Light Arrow, in=-120, out=165, looseness=2.00] (21) to (18);
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		\draw [style=Light Arrow] (21) to (5);
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		\draw [style=RightArrow] (20) to (5);
		\draw [style=RightArrow] (22) to (0);
		\draw [style=RightArrow, bend left] (20) to (0);
		\draw [style=PurpleArrow] (1) to (0);
		\draw [style=PurpleArrow] (1) to (5);
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		\draw [style=lightredarrow] (22) to (5);
		\draw [style=lightredarrow] (5) to (22);
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