Several linear regression research was first utilized, followed by a study of the possibility of an effective nonlinear dating present of the including quadratic and cubic versions. Adjusted [R.sup.2] and you will important mistake out of estimate (SEE) viewpoints were used evaluate new overall performance of your own predictive model from BF%.
The reports out-of p was indeed a couple-sided and you can p below 0.05 is actually thought statistically high. All analyses was did playing with STATA software version several.0 (STATA Corp, School Channel, Tx, USA) and SPSS adaptation 17.0 (SPSS Inc., Chi town, USA).
3.1. Study Population and Baseline Characteristics. All 2,771 participants in this study were over 18 years and comprised 64% women with a median age of 52 years (IQR, 43-60) and 36% men with a median age of 60 years (IQR, 47-68). The BF% in men was statistically significantly lower than in women (27% and 34%, resp.; p < 0.001). The difference in HWDI between men and women was also statistically significant (101 [IQR, 95-107] for men and 98 [IQR, 92-104] for women; p < 0.001) (see Table 1).
Within study, HWDI, a somewhat the obesity dimensions sign, is actually found to own an inverse relationship with BF% in everyone
Figure step 1 shows the partnership ranging from average Body mass index and you will years. It actually was unearthed that, on the period of 18 to help you 39 years, brand new indicate Bmi grows just like the many years increases however,, immediately following getting together with sixty years of age, the suggest Body mass index reduces since age develops (discover Profile 1(a)). The opposite is available with the relationship anywhere between suggest HWDI and you may age.
3.2. Relationship between HWDI and BF%. Figure 2 shows the relationship between HWDI and BF%. Pearson’s correlation coefficient (r) = -0.200 (p < 0.001) in men and r = -0.473 (p < 0.001) in women. In contrast, the direct relationship was found between BMI and BF%, r = 0.144 (p < 0.001) in men and r = 0.421 (p < 0.001) in women. Furthermore, the relationship between HWDI and BF% was statistically significant even when analyzed with respect to age group and gender (p < 0.001) (see Figure 3).
Statistically, a keen inverse dating anywhere between HWDI and you can BF% are discover due to the fact HWDI improved while you are BF% worth notably reduced
3.3. The Effect of Age, Gender, and HWDI on BF%. The study of the effect of age, gender, and HWDI on BF% showed all three variables’ relationship with BF% to be statistically significant for building a prediction model (p < 0.001 for all variables). HWDI and BF% by age and gender resulted in r = -0.629/ - 0.518 (men/women) for the 18-39-year age group, r = -0.372/ - 0.560 for the 40-59-year age group, and r = -0.125/ - 0.369 for age group over 60 years (see Figure 3).
3.4. Predictive Modeling of BF% by Gender. In this study, several forms of relationship between HWDI and BF% were studied: linear, quadratic, and cubic. However, Figure 3 shows that the relationship tended to be in linear form more than the others, and so we elected to use a linear form in the construction of the BF% prediction model. The results of a multivariate linear regression analysis, which includes the HWDI and age variables, yielded a BF% for men of — 0.159 (HWDI) + 0.161 (age) [adjusted [R.sup.2] = 0.215, standard error of estimate (SEE) = 5.37%, p < 0.001], and, for women, - 0.265 (HWDI) + 0.132 (Age) [adjusted [R.sup.2] = 0.337, SEE = 4.39%, p < 0.001] (see Table 2).
But not, Pearson’s correlation coefficients was seen to be low (r = -0.20 for males and you may r = -0.47 for women) when compared with past education you to definitely utilized almost every other obesity evaluation systems with BF% [16,18, 19]. During the 1996, Gallagher mais aussi al. studied the connection between Bmi and BF% and advertised beliefs out of roentgen = 0.58 for men and you will roentgen = 0.72 for women. Ilman mais aussi al. has claimed roentgen = 0.85 https://datingranking.net/nl/chatfriends-overzicht/ for men and you can roentgen = 0.83 for females. For every single data discussed a definite BF% anticipate design. It was in earlier times reported that, along with ages and you may sex, additional factors particularly nationality, ethnicity, and you will faith may also be helpful help the accuracy from an effective BF% anticipate design [16,19-23].