Since there were no standard procedures in place at the three facilities for patient follow-up, it was problematic to assess this cost.
Two thirds of the physicians (64.4 %) answered that it was problematic to assess work capacity for unemployed patients, which makes this task the one that the highest proportion of physicians rated as problematic.
Owing to the essential requirement for cilia during development, it has been problematic to assess the function of cilia postnatally using conventional mouse mutants.
However, the subcellular localization and phosphorylation state of the protein are critical in regulating its activity, and it would, therefore, be problematic to assess these changes in clinical samples.
It can also be problematic to assess the use of co-interventions and the level of compliance, as both of these may merely reflect the differential effects of the studied interventions.
Since inversions are relatively rare events, and it is unlikely that multiple patients with the same inversion are found, it is often problematic to assess whether the inversion present in the patient is actually associated with the phenotype.
It would be problematic to use total fluoride exposure to assess dose response in this population on this study and it should be accepted the use of cooking water fluoride content is not indicative when evaluating a dose response.
This important endpoint is more problematic to assess than other endpoints [2].
Gene suppression by RNAseH, silencing, or translational blockade can be more problematic to assess because the disappearance or reduction in abundance of a transcript or protein is measured in a negative assay.
However, imputed data can be problematic to use for assessing the measurement properties of an instrument, as imputed data will artificially reduce variation in overall scores.
According to a recent study, physicians who worked in occupational health service and who had a well-established workplace policy regarding sickness certification matters were likely to find it less problematic to assess and provide a long-term prognosis of work capacity [ 45].
