document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=820584>Question 820584</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 7.	A clinical trial is run to investigate the effectiveness of an experimental drug in reducing preterm delivery to a drug considered standard care and to placebo.  Pregnant women are enrolled and randomly assigned to receive either the experimental drug, the standard drug or placebo.  Women are followed through delivery and classified as delivering preterm (< 37 weeks) or not.  The data are shown below.\r<BR>\n" );
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document.write( "Preterm Delivery	Experimental Drug	Standard Drug	Placebo<BR>\n" );
document.write( "Yes	17	23	35<BR>\n" );
document.write( "No	83	77	65\r<BR>\n" );
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document.write( "Is there a statistically significant difference in the proportions of women delivering preterm among the three treatment groups?  Run the test at a 5% level of significance<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #493652 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=493652\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Women are followed through delivery and classified as delivering preterm (< 37 weeks) or not.  The data are shown below.\r<BR>\n" );
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document.write( "Preterm Delivery	Experimental Drug	Standard Drug	Placebo<BR>\n" );
document.write( "Yes	                      17	             23	          35<BR>\n" );
document.write( "No	                      83	             77	          65\r<BR>\n" );
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document.write( "Is there a statistically significant difference in the proportions of women delivering preterm among the three treatment groups?  Run the test at a 5% level of significance<BR>\n" );
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document.write( "Ho: The rows have the same proportions<BR>\n" );
document.write( "Ha: The proportions are different<BR>\n" );
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document.write( "I ran a Chi=Square program against the data and got the following::<BR>\n" );
document.write( "test stat:: Chi-Sq = 8.9600<BR>\n" );
document.write( "p-value = 0.0113<BR>\n" );
document.write( "df = 2*1 = 2<BR>\n" );
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document.write( "Conclusion:Since the p-value is less than 5%, reject Ho.<BR>\n" );
document.write( "Conclusion: There is a statistical difference in the proportions.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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