Comparison of Male Adult BMI in Australia: Sample vs Population Mean Difference

The comparison of sample and population mean difference in the body mass index (BMI) of male adults in
Australia
Introduction
Each and every country in the world have been striving to ensure that its citizens lead healthy
lives free from any sort of diseases such as cancer, polio, diabetes and not limited to obesity
among other diseases. Obesity is a worldwide health concern both in the developed countries like
Australia and developing countries. Obesity has been associated with excessive deposition of fats
in the body by the medics and health experts (Wang et al, 2015). It (obesity) has been as well
defined as over-accumulation of fats in the body (Ogden et al, 2015). In America, nearly 40% of
the Americans were suffering from obesity. Australia in particular among other countries across
the globe have been at the forefront in fight to reduce the rate of overweight and obesity increase
among its citizens. The country had shown the endless efforts of reducing obesity through
proposing dietary guidelines to its citizens in order for them to maintain healthy body weight
(NHMRC, 2013). In addition to that, Australian government through the Ministry of health
encourage its citizens to adhere to the diet consistent with that proposed by the government
through its health experts.
Overweight or obesity is as a result of imbalance of energy in the body through intake of either
drinks or eating rich energy content foods than the amount of energy required by the body for its
daily activities (AIHW, 2016a). From reports and statistics, Australia have had in the recent past
mean height of 175.6 cm for adult males and 161.8cm for adult females. Since weight goes hand
in hand with the height, the mean weight of both genders in the country was reported to be
85.9kg and 71.1kg for adult males and adult females respectively. Applying these values in

calculation through the formulaBMI = wieght (kg )
height2 (m)2 , mean body mass index (BMI) for the adult
males and adult females was 27.8576 kgm-2 and 27.1589 kgm-2 respectively. In response to that,
this report was aimed at comparing the population mean BMI for Australian adult males to the
sample mean of BMI drawn from the same population.
Research objective
1. To determine mean difference of male adult BMI in the sample to that of the population
Research question
In order to meet the above stated research objective, the report had to answer the following
research question.
1. Is there mean difference of male adult BMI in the sample to that in the population?
Methodology
Numerical data was collected from a sample size of (n = 10) male individuals. The individual
participants were randomly picked from the population in order to reduce biasness in the data
collection process. The participants were asked of their height and weight which were then used
to calculate the body mass index (BMI). The researcher employed t-test in the test of the
hypothesis that the sample BMI mean of male adults was equal to the population BMI mean of
male adults. The collected data were as in the below table:

Table 1: Sample collected data
Height
(m)
Weigh
t (kg) BMI
1.579 68
27.273
74
1.782 80
25.192
69
1.708 84
28.794
1
1.9 86.8
24.044
32
1.856 87.1
25.284
96
1.745 84.3
27.684
5
1.65 78.9
28.980
72
1.59 68.7
27.174
56
1.785 82.1
25.767
17
1.74 80.4
26.555
69
Results and hypothesis testing
Hypothesis
H0: The sample mean of male adult BMI is equal to the population mean of male adult BMI
H1: The sample mean of male adult BMI is not equal to population mean of male adult BMI
Level of significance (α)
Level of confidence was chosen to be at 95% thus translating to level of significance of 5% or
(α=0.05)
Critical value (t-table)