Base on the following Table, taken from a linear regression from the article, Jo

Question

Base on the following Table, taken from a linear regression from the article, Joossens JV et al: Dietary salt, nitrate and stomach cancer mortality in 24 countries. Int J Epid. 1996 25(3): 494-504. The outcome is age-adjusted stomach mortality rate. Remember that this is a linear regression. (You do NOT need the article).

Table 3 (both models) directly indicates which of the following?

A. Na and Nitrate appear protective against stomach cancer.

B. Na and Nitrate appear synergistic in their association with stomach cancer.

C. The combined effects of Na and Nitrate appear to be much greater than multiplicative.

D. All of the above  

Table 3: Linear Multiple Regression of Stomach Cancer Mortality, Age-Adjusted 45-74 years, Rate/100,000 year, Against Average Daily Sodium (Na) and Nitrate Excretion (mmol/24-hrs) 20-49 Years, N-24 Countries Men Coeff (SE) Adjusted R2 Model 1 Stomach cancer mortality related to median 24-hour urinary sodiurn and nitrate Na Nitrate 0.679 (0.176) 21.97 (7.17)* 0.61 Model 2 Stomach cancer mortality related to median 24-hour urinary sodium and nitrate and their interaction Na Nitrate Na Nitrate 0.219 -130 0.77 0.763 (0.199)* For Clarity, the following is copied from the Table 3 above so you can read it: Model 1 interaction term Coefficient 0.679 Na Nitrate 21.97 Model 2 Parameter Na Nitrate Na X Nitrate nteraction term Coefficient 0.219 130 0.763**

Explanation / Answer

Model:--1)

Urinary Sodium = 67.9%

Nitrate = 21.97%

Positive correlation.

adjusted R2 = 0.61 ==> 61%

Probability of protective against stomach cancer mortality by Na and Nitrate is 0.61.

Model : 2)

Urinary Sodium = -0.219

Nitrate = -130

Negative correlation

Sodium versus Nitrate = 0.763

Adjusted R2 = 0.77 ==> 77%

R2 which is the value of coefficient of determination.

High coefficient of determination = 77% from model --(2)

which is the probability of protective against stomuch cancer mortality by Na and Nitrate.

Answer : (B) Na and Nitrate appear synergistic in their association with stomuch cancer.

Related Questions

Navigate

• Browse (All)
• Browse B
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.