Table 1: Reliability and validity of body composition measurements in individuals with intellectual disabilities.

Author(s)Subjects mean (SD)MeasureRegression equation Reference methodResults: reliability and validitySummary

Usera et al. (2005) [21]14 adults with DS; 38(11) yrs.SKF
AGM
SKF:
Jackson and Pollock [22].
AGM: Kelly et al. [23]; Lohman [24]
ADP with BOD
POD
Validity: correlations with reference method and RMSE: Jackson et al. ( ), RMSE = 14.90; Lohman ( ), RMSE = 13.20; Kelly and Rimmer ( ), RMSE = 9.82.Lack of validity in 3-field-based methods.
New equations for DS recommended
Verstraelen et al. (2009) [18]76 adults with ID; 19–72 yrs.BMI
WC
BIA
SKF
Jackson et al. [25];
Durnin and Womersley [26]
Reliability: Cohen’s kappa with 90% CI. Intertest agreement among BMI & WC (0.61). Agreements between BMI SKF & FFM index, WC to SKF & FFM and SKF to FFM (<0.6)BIA & WC feasible measures. Lack of reliability and large noncompliance for both SKF ( ) and FFMI (BIA) ( ).
Waninge et al. (2009) [19]45 severe ID; 38(11) yrs.BMI
WC
SKF
Tibia length
Reliability: ICC for all variables (95% CI) except SKF (>0.90).Measuring tibia
length possible.
Noncompliance and low reliability noted for all SKF measurements
Temple et al. (2010) [17]46 adults mild to mod ID; 19–60 yrs.BMIDXAValidity: BMI accounted for 68% of variance in %BF ( ). Partial correlation of BMI with fat
( ) and fat-free
mass ( )
BMI reasonable indicator of adiposity.
Rieken et al. (2011) [16]61 children w/neurol. disability and severe ID; 10(4) yrs.SKF
BIA
Tibia length
SKF: Gurka et al.[27]; Rieken et al. [16]
BIA: Pencharz and Azcue [28]; Rieken et al. [16]
Isotope dilutionValidity: ICC SKF-Gurka et al. [27] mean Difference = −9.2 ± 16.7; ICC = 0.51; SEE = 5.1 kg; = 0.27; Rieken et al. ICC = 0.59; SEE = 7.6 kg; =0.44; SEE = 2.2 kg; = 0.88;
BIA- Pencharz and Azcue [28] Mean difference = 2.6 ± 4.4; ICC = 0.94; Rieken et al. ICC = 0.96; SEE 1.7 kg; = 0.92
SKF met with noncompliance ( ). Low
reliability and validity for SKF compared to BIA.
Gonzalez-Aguero et al. (2011) [20]28 children with DS; 10–20 yrs.SKFSlaughter et al. [29];
Durnin and Womersley [26];
Johnston et al. [30];
Brook [31]
ADPValidity: Slaughter et al. [29] ( ( )); mean difference = 0.69; 95% CI = 25.8; Durnin and Womersley [26] ( ( )); mean difference = 2.34; 95% CI = 18.0; Johnston et al. [30] ( ( )); mean difference = 2.73; 95% CI = 19.6; Brook ( ( )); mean difference = −2.45; 95% CI = 22.3Slaughter’s equation
most accurate despite
wide LOA. Other
equations displayed
substantial intermethods difference
and under- or overestimation of % BF.

ID: intellectual disability; DS: Down syndrome; AGM: anthropometric girth measurements; SKF: skinfold; BIA: bioelectrical impedance analysis, ADP: air displacement plethysmography; WC: waist circumference; FFMI (BIA): fat-free mass index derived by bioelectrical impedance analysis; %BF: percent body fat; ICC: intraclass correlation coefficients; CI: confidence interval; : coefficient of correlation; LOA: limits of agreement.