The following report is a description based on the information obtained from the participants involved in the study of a skin cancer prevention trial.
Variables
There are a total of 385 participants with an age range of 25 to 74. Among these, 172 members are males and 213 are females. Their body mass indices are 18.5-24.9 kg/M2 in 151 normal-weight subjects, 25-29.9 in 168 overweight subjects, and above 30 in 66 obese subjects.
A normal cholesterol level of less than or equal to 5.5 mmol/L and a high level of more than 5.5 mmol/l was observed in 178 and 207 subjects, respectively. Their mean high-density lipoprotein (HDL) levels are 1.49 mmol/l, with a maximum of 3.78 mmol/l and a minimum of 0.71mmol/l. A high blood pressure (B.P) was observed in only 104 subjects.
Scientific Hypotheses
The cholesterol levels vary with age linearly. This is evident from the report that at the age of 25, cholesterol levels were 3.29 mmol/L, and at 74, the levels were 9.19 mmol/L. Next, high B.P is strongly associated with abnormal BMI. This is evident from the report that 28 of 66 obese subjects (42.4%) are showing high BP status compared to 55 of 168 overweight subjects (32.7%), and 21 of 151 normal-weight subjects (13.9%).HDL levels have differed with slight significance between males and females. An abnormal mean value of 1.3034 mmol/L in males and the normal mean value of 1.6457 mmol/L in females. Further, the mean HDL levels are slightly abnormal in obese weight and overweight BMI groups.
Data Summary
Based on the above information on each identified variable, it can be summarized that subjects with mean values of 50 years and 26.4 kg/m2 BMI have mean levels of 5.7 mmol/L cholesterol, 1.78 mmol/L triglycerides, and 1.49 mmol/L HDL.
Here mean values were given importance as they are significant in furnishing valuable information on interpretation.
Data Comparison
The first hypothesis can be tested by a simple correlation test since a linear relationship between the two variables age and cholesterol could be easily determined. Cholesterol levels were found to increase with age. This may indicate that cholesterol levels gradually turn abnormal following the advancement of age and might contribute to further risk of Coronary heart disease (CHD). The second hypothesis can be tested by ANOVA test because there are 3 different groups of BMI identified. Here, ANOVA can better help in finding the differences in cholesterol between the BMI classes or groups. Since high B.P was found to be associated with BMI, it may indicate that blood pressure is likely to elevate with high BMI. Therefore, patients with high BMI may be at an increased risk of high B.P initiated disorders.
To test the third hypothesis, a t-test for independent samples is used. Because this test better helps in evaluating the differences between the two mean values of HDL in males and females. HDL levels of 1.5 mmol/L or higher were reported to protect against heart disease and males were found with an HDL level of 1.3034 mmol/L compared to females with 1.6457 mmol/L in the present report. Here, it can be inferred that slight abnormal HDL levels observed in the male subjects may indicate that men are at risk of developing CHD.
The fourth hypothesis can be again tested by ANOVA test because there are 3 different groups of BMI identified. Here, ANOVA can help in better finding the differences of HDL levels among three BMI classes. It was found that overweight and obese subjects have their mean levels of HDL below 1.5 mmol/L.It may indicate that they are at risk of developing CHD.
Summary
From the above description, it is clear that the variables identified in the participants involved in the study of skin cancer prevention trials have yielded valuable information regarding a possible association with coronary heart disease (CHD). It was found out that the variables are related to one another either significantly or insignificantly.
The link between Age and cholesterol levels may be an indication of age related risk of CHD. Increased BMI levels of overweight and obese subjects are showing a predisposition to high B.P and abnormal HDL levels. Finally, men are likely to increase their chances of developing CHD due to their abnormal HDL levels.
Table showing summary of results of two hypotheses:
References
Cholesterol and Triglycerides Test. 2008. Web.
www.liu.edu
www.csiro.au