There were no statistically significant differences found between the characteristics of participants and non-participants, except the proportion of unknown levels of gross motor function (Table 1).
Because of the unknown level of errors in the sequences, a conservative approach to estimating the mutation rate was taken.
Sight-resight experiments in limited areas are also vulnerable to unknown levels of mixing across the boundaries of the area that can bias the results.
The purpose of this research was to determine the level of radiation damage in the lymphocytes collected from donors exposed to unknown levels of chronic γ radiation in order to estimate the potential health impacts.
Response rates to postal surveys of healthcare professionals are low and probably declining, almost certainly leading to unknown levels of bias.
These results suggest that estimates of harm rates from CRRs could contain unquantifiable upward bias due to unknown levels of inter-patient variation.
The conclusion drawn in 2005 was that response rates to postal surveys of healthcare professionals were low and probably declining, which may lead to unknown levels of bias [ 27].
Genotyping studies of multilocus MHC genes using NGS are prone to inaccurate allele-calling caused by both artefacts and unnoticed allelic dropout, especially due to the lack of matured approaches to deal with large amounts of data with an unknown level of complexity.
Obstacles to complex trials include a difficulty to make experimental practice changes, ideological resistance to or ignorance of trials, unknown levels of generalizability, and costs.
