The Essentials of Biostatistics for Physicians, Nurses, and Clinicians

8.7 Exercises 143

Table 8.16

Relationship Between Race and Smoking Status

Race Current

smoker

Quit

smoking

Never

smoked

Total

African American 40 34 40 114

Asian 33 34 65 142

Hispanic 117 92 70 279

Native American 20 28 12 60

European American 202 232 214 648

Total 412 430 401 1243

Table 8.17

Relationship Between Smoking and Alcohol Consumption

Smoking

status

Current

alcohol user

Light

alcohol user

Former

alcohol user

Never used

alcohol

Total

Heavy 40 24 10 40 114
Moderate 33 30 49 30 142
Light 30 72 20 38 160
None 110 158 232 339 839
Total 213 284 311 447 1255

6. A clinical trial is conducted at an academic medical center. Diabetic patients
   were randomly assigned to a new experimental drug to control blood sugar
   levels versus a standard approved drug using a 1 : 1 randomization. Two
   hundred patients were assigned to each group, and the 2 × 2 table (Table
   8.18 ) shows the results.
   Test at the 5% level to determine if the new drug is more effective. Is
   it appropriate to apply the chi - square test? Why would it be diffi cult to do
   Fisher ’ s test without a computer? How many contingency tables are pos-
   sible with the given row and column marginal totals?


7. A study involving 75 patients who at one time used sodium aurothiomalate
   (SA) as a treatment for rheumatoid arthritis. The purpose was to examine
   whether or not the toxicity of SA could be linked to the patients sulphoxi-
   dation capacity assessed by the sulphoxidation index (SI). For SI, a value
   of 6.0 was used to separate impaired sulphoxidation (SI > 6.0), with unim-