We used a new methodology to estimate in-hospital risk associated with each of these variables.
One of the most common assessments of reliability is Cronbach’s Alpha, a statistical index of internal consistency that also provides an estimate of the ratio of true score to error in Classical Test Theory.
In this example, the overall reliability statistic is .732.
The analysis also elucidates the efficacy of each individual item by reporting information such as corrected item-total correlation and Cronbach’s Alpha if an item were deleted.
We then constructed a heuristic model quantifying patient condition (overall risk) by summing the single-variable risks.
The model’s validity was assessed against outcomes from 170,000 medical-surgical and critical care patients, using data from three US hospitals.