Shoe SIZE

Study of Shoe Size



Study of Shoe Size

The anatomic parameters of human body such as height, weight and the size of some specific parts of it have been thoroughly studied in literature for various purposes. However, it seems that the correlation between some of those parameters in order to estimate human height and weight has not been studied in particular.

The development of the human foot and the age in which its size approaches that of the mature human skeleton constitute points of interest. The acquisition of the mean values and of the standard deviations of those variables might be useful in treating surgical pathologies such as talipes equinavarus, flat foot or varus metatarsal. and other familiar or acquired abnormalities in a way that it can help making a treatment decision.

The sample of the study consisted of 5093 children (2535 boys, 49.77%, 2558 girls, 50.23%). The response ratio was 96.93%. The average age of the sample was 11.47 ± 2.71 years.

The descriptive statistics such as the means and standard deviations for the dependent variables (height, weight) as well as the independent variables ( age, right foot length, left foot length) are classified by sex and are shown in Table 1. According to the results, a significant difference was found in right and left foot length between the two genders. The age, height and weight did not differ significantly.

Table 1.

Descriptive statistics of the main characteristics of the study and comparisons between sexes

Sex

Boys

Girls

Mean

SD

Min

Max

Mean

SD

Min

Max

p-Value

Age (years)

11.37

2.69

5.49

20.06

11.36

2.73

5.99

18.46

0.989

Height (cm)

147.44

16.78

105.00

202.00

146.80

14.49

107.00

183.00

0.145

Weight (Kg)

45.04

16.77

17.00

119.00

44.79

14.44

16.00

109.00

0.573

Left foot length (cm)

22.50

2.54

16.00

29.00

21.71

2.01

15.00

29.00

<0.001

Right foot length (cm)

22.43

2.56

15.00

28.00

21.71

2.01

15.00

27.00

<0.001

Age categories

N

Percentage

N

Percentage

4-6 Years

140

5.52

135

5.28

0.062

7-9 Years

685

27.02

630

24.63

10-12 Years

943

37.20

942

36.83

13-15 Years

670

26.43

721

28.19

16-18 Years

97

3.83

130

5.08

Total

2535

100.00

2558

100.00

The simple bivariate Pearson r correlations between the dependent and independent variables are shown for both genders in Table 2. All coefficients were statistically significant (p < 0.001) and indicated a linear relationship between the variables. The relationships described were rather strong, not falling below 0.733. The relationship between right and left foot length and height was stronger in boys than in girls (0.903, 0.898 vs. 0.855, 0.856, respectively). The above difference was also found regarding the two main independent variables and weight (0.818, 0.808 vs. 0.756, 0.757, respectively).

Simple bivariate correlations between dependent variables (height and weight) and independent variables ( age, right and left foot length) by sex

Boys

Girls

Height (cm)

Weight (Kg)

Height (cm)

Weight (Kg)

Age (years)

Pearson correlation

0.877

0.766

0.841

0.733

p-Value

<0.001

<0.001

<0.001

<0.001

Left foot length (cm)

Pearson correlation

0.898

0.808

0.856

0.757

p-Value

<0.001

<0.001

<0.001

<0.001

Right foot length (cm)

Pearson correlation

0.903

0.818

0.855

0.756

p-Value

<0.001

<0.001

<0.001

<0.001

The scatter-plot matrix describing all possible relationships between the independent and dependent variables for each gender is shown in Fig. 1. The linear relationship which was calculated using Pearson r in Table 2 is described graphically in those matrices. Four univariate linear regression models were constructed. The dependent variables were height and weight, whereas, the independent variables were right and left foot length. All models were found to be statistically significant (F-test p-value < 0.001). The results of the univariate linear regression models are shown in Table 3.

Fig. 1. Scatter-plot matrix representing the relationships between the dependent variables (height, weight) and the explanatory variables (right and left foot length, age) for both sexes.

Table 3.

Four univariate linear regression models

Height (cm)

Unstandardized coefficient ...