GRADE suggests that examination of 95% confidence intervals (CIs) provides the optimal primary approach to decisions regarding imprecision. Results are considered imprecise when studies include relatively few patients and few events and thus have wide confidence intervals around the estimate of the effect. In this case a guideline panel will judge the quality of the evidence lower than it otherwise would because of resulting uncertainty in the results.
As a general principle GRADE recommends to consider the rating down for imprecision If a recommendation or clinical course of action would differ if the upper versus the lower boundary of the CI represented the truth. In order to judge this the clinical decision threshold needs to be defined. We explain the situation for both categorical and continuous outcomes.