Question

Researchers were interested in whether patients with a history of angina are more likely to take anticoagulant drugs. (5 points)

angina2 * Taking anticoagulant drugs Crosstabulation
			Taking anticoagulant drugs		Total
			Yes	No
Angina	Yes	Count	311	25	336
		Expected Count	177.3	158.7	336.0
		Std. Residual	10.0	-10.6
	No	Count	242	470	712
		Expected Count	375.7	336.3	712.0
		Std. Residual	-6.9	7.3
Total		Count	553	495	1048
		Expected Count	553.0	495.0	1048.0

	Value			df	Asymp. Sig. (2-sided)			Exact Sig. (2-sided)	Exact Sig. (1-sided)
Pearson Chi-Square	314.204			1	.000
Continuity Correctionb	311.859			1	.000
Likelihood Ratio	358.893			1	.000
Fisher's Exact Test								.000	.000
Linear-by-Linear Association	313.904			1	.000
N of Valid Cases	1048
		Value	95% Confidence Interval
			Lower			Upper
Odds Ratio for angina2 (Yes / No)		24.160	15.623			37.363
For cohort Taking anticoagulant drugs = Yes		2.723	2.447			3.030
For cohort Taking anticoagulant drugs = No		.113	.077			.165
N of Valid Cases		1048

1. Identify the null and alternate hypothesis.
2. Interpret test statistic and state conclusion based on original hypothesis. Assume alpha = .05
3. Interpret the odds ratio based on original research hypothesis.

Interpret the relative risk for those patients who take anticoagulant medications

Answer 1

Researchers were interested in whether patients with a history of angina are more likely to take anticoagulant drugs.

Identify the null and alternate hypothesis.

Ho: There is no association between history of angina and taking anticoagulant drugs

H1: There is an association between history of angina and taking anticoagulant drugs

Interpret test statistic and state conclusion based on original hypothesis. Assume alpha = .05

Calculated chi square 314.204 , P=0.000 which is < 0.05 level of significance. Ho is rejected. We conclude that there is significant association between history of angina and taking anticoagulant drugs

Interpret the odds ratio based on original research hypothesis.

Odds ratio =24.16

People with history of angina are taking anticoagulant drugs 24.16 times more compared to People with no history of angina.

Interpret the relative risk for those patients who take anticoagulant medications

relative risk = (311/553)/(25/495) = 11.14

The relative risk of taking anticoagulant medications is 11.14 times that of people with history of angina compared to no history of angina.