A possible explanation for the poor agreement we observed between EtCO2 and PaCO2 during NIV could be the presence of a high airflow and of significant and often variable leaks during NIV that may have caused sampled expiratory gas dilution.
Finally, this study was performed using a single-center design and the sample size was relatively small, which may cause potential sampling errors.
Several means of a process analysis are employed to assess the sampling and intervention quality, e.g., characteristics that may cause selective sampling of participants (e.g., residents' depressive symptoms) are documented as well as the frequency of participation, questionnaire-based evaluations of each staff training session, and supervision of staff's application of learned techniques.
In the words of the authors, "The analysis showed that previous studies have utilized inconsistent criteria to define internet addicts, applied recruiting methods that may cause serious sampling bias, and examined data using primarily exploratory rather than confirmatory data analysis techniques to investigate the degree of association rather than causal relationships among variables".
In the words of the researchers, "The analysis showed that previous studies have utilised inconsistent criteria to define internet addicts, applied recruiting methods that may cause serious sampling bias and examined data using primarily exploratory rather than confirmatory data analysis techniques to investigate the degree of association rather than causal relationships among variables.
Additionally, potential regional variability may cause meaningful sampling variability [ 48].
Because the nests of tumor cells tend to be heterogeneous in distribution within the tumor, a measurement of ADC values by manual drawing of the region of interest from the imaging (ADC map) may cause significant sampling bias.
Other strategy is to eliminate all zero bids, but this may cause a sample selection bias since the remaining bids no longer originate from a random sample of the basic population (Romer 1992).
Other strategy is to eliminate all zero bids, but this may cause a sample selection bias, since the remaining bids from no longer originate from a random sample of the basic population (Romer [1992]).
