Table 4 Estimation of the parameters associated with the covariates explaining the mean of the latent trait “Physical Functioning” (β _μ ) and with the covariates explaining the variance of the latent trait (γσ ² )

Variables explaining the mean of the latent trait (β_μ)

Constant (μ*)

3.1131

0.0834

<0.0001

Women

−1.1154

0.0816

<0.0001

Survey 2003

−0.2447

0.0512

<0.0001

Ager

−0.5960

0.0110

<0.0001

North

−0.2809

0.0696

<0.0001

Western Paris Basin

−0.1386

0.0723

0.0554

West, South-West, South-East

0.3284

0.0525

<0.0001

Women*Ager

0.0667

0.0127

<0.0001

Ager*(North, Eastern Paris Basin, West, South-West, South-East)

−0.0345

0.0079

<0.0001

Variables explaining the variance of the latent trait (γσ²)

Constant (σ²*)

8.9934

0.5003

<0.0001

Women

−2.4176

0.4027

<0.0001

Survey 2003

3.0001

0.4436

<0.0001

Ager

−0.5758

0.0650

<0.0001

Women*Ager

0.1404

0.0533

0.0084

Survey 2003*Ager

−0.2560

0.0595

<0.0001

Explained variance

Estimated variance without covariates: ${\widehat{\sigma }}_0^2$ (k₀)

9.3182 (21)

Estimated variance with covariates: ${\widehat{\sigma }}^2$ (k)

6.8119 (30)

Rate of explained variances: _τ

27%