Utilizing the heavy peptide signals as an internal standard (by calculating the peak area ratio, or in log scale, subtracting the logs of heavy peptide measurements), removes this source of experimental variability.
There may be instrument error issues as well, and averaging measurements across monitors may help to dampen this source of measurement error [ 16, 26, 30].
A measurement design which eliminates this source of uncertainty is presented and tested.
More in-depth analysis, focused on using measures of group dynamics as covariates might shed some light on the importance of this source of measurement error in our design.
Therefore, it is expected that asking children directly would reduce this source of measurement error.
Because intraindividual variability can contribute to misclassification, using urinary As concentrations would reduce this source of measurement error and potentially improve statistical precision.
In previous work on rats, we have found that small differences in measurement style between weeks can cause estimates of testis volume to fluctuate by approximately 10% from week to week [ 5], and that use of running three-point point means reduces this source of measurement error [e.g. [ 36]].
