Sentence examples for usually difficult to ascertain from inspiring English sources

First, the study design was a retrospective cross-sectional analysis, for which it is usually difficult to ascertain the temporal sequence of exposure and outcome.

The method is directly applicable not only to fecal samples but also to other types of clinical samples; it could detect and identify bacterial pathogens that are usually difficult to ascertain with conventional examination procedures.

It is usually difficult to ascertain the benefit of a marker from a single published study, which may be overoptimistic owing to small sample size and selective reporting, and a clear view is only likely to emerge from looking across multiple studies.

The group is moving into the quieter summer months, the spring selling season is usually bigger than the autumn one and it is difficult to ascertain how much of the first half demand was 'pent up' or sustainable.

The sole Antarctic species, Kamptosoma asterias, is usually considered an echinothurioid, but its unusual morphology has made its position difficult to ascertain.

score difficult to ascertain.

The net effect of their impact is difficult to ascertain.

How widespread these cases are is difficult to ascertain.

Basic Contradictions Just who David Chang is has been difficult to ascertain.

It is Iran -- not Iraq -- whose true policy on the issue has been difficult to ascertain.

It is difficult to ascertain from the volunteers which ones might seek such a role.