Several linear regression data was initially utilized, accompanied by an examination of the potential for a nonlinear matchmaking current from the and additionally quadratic and you can cubic variations. Modified [Roentgen.sup.2] and you may practical mistake out-of estimate (SEE) values were utilized to compare this new performance of predictive model off BF%.
All of the account from p was basically one or two-sided and p below 0.05 are felt mathematically extreme. All the analyses had been performed having fun with STATA application type a dozen.0 (STATA Corp, College or university Station, Tx, USA) and you can SPSS version 17.0 (SPSS Inc., Chicago, 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 comparatively the brand new obesity dimensions indicator, is actually discovered having an enthusiastic inverse relationship with BF% both in individuals
Profile step one reveals the partnership between mediocre Body mass index and decades. It absolutely was discovered that, throughout the age 18 so you can 39 decades, the fresh new suggest Bmi increases due to the fact age develops but, shortly after getting 60 yrs old, this new suggest Bmi reduces since age increases (get a hold of Contour step 1(a)). The opposite can be acquired toward relationships ranging from indicate HWDI and you may ages.
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).
Mathematically, a keen inverse dating ranging from HWDI and you can BF% try discover because the HWDI enhanced when you’re BF% worth significantly diminished
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).
Although not, Pearson’s correlation coefficients was in fact found to be lower (r = -0.20 for men and roentgen = -0.47 for females) when compared with prior training one to made use of almost every other carrying excess fat analysis equipment having BF% [16,18, 19]. When you look at the 1996, Gallagher et al. analyzed the partnership anywhere between Body mass index and BF% and you will claimed thinking off r = 0.58 for men and you will r = 0.72 for females. Ilman mais aussi al. have advertised r = 0.85 for males and you may r = 0.83 for females. For every data demonstrated a definite BF% forecast design. It was in past times reported that, besides many years and gender, additional factors such nationality, ethnicity http://sugardaddydates.org/sugar-daddies-usa/ny/, and you may faith may also be helpful improve precision regarding a BF% forecast model [16,19-23].
