cross-condition meaning in medical section text?

I read this article:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5362694/

author says "Walraven and colleagues [11] developed the “LACE” index, a cross-conditions tool that predicts early death or unplanned readmission after discharge from hospital"

what does mean by cross-condition is simplest term?

Solution 1:

There are four aspects (termed conditions within the article) of a patient's history that influence the likelihood of their returning to hospital after a previous stay there. Each aspect is scored according to suitable criteria. To take just one example, if the patient has been admitted to an emergency department once/twice/three times in the previous six months, the score for this condition is respectively 1/2/3.

The term "cross-condition" is adjectival, merely describing the LACE index as a combination of the scores for all four conditions (i.e. a score that crosses all conditions). The nature of the index is that it does not depend directly on any single condition but on a simple arithmetic combination (in this case, the sum) of scores for each of the conditions. A cross condition index is therefore nothing more than an index (score) composed from the scores of each of the four contributing conditions.

I add that this technique of reducing scores from a number of variables to a single score somehow hoped to represent the whole set is common when presenting complex data in a simple way. Key Performance Indicators in business may combine measures of several things (fraction of faulty goods, number of complaints, average invoice payment time ...). Environmental Quality Indices combine several measures of environmental health in one scale that is derived (not necessarily by simple totaling of individual scores) from them in various ways. I do not quote references because you may easily find example on a search for "Quality index". These indicators are all equivalent to cross-condition indexing as in the article you quote.

In simplest summary, the cross-condition index (or score) is the total of the scores across all the four conditions. For example, scores of [2,5,3,2] give a cross condition score of 12.

Solution 2:

The LACE Index for Readmission is a means of evaluating patients to see their likelihood of being readmitted to the hospital. There are four steps that look at different conditions. The fact that it us using different conditions gives it the name Cross-conditional as the conditions are of distinctive contrasting descriptions.

The LACE index is made up of several things: Length of stay, Acuity or severity of their admission, Comorbidities, meaning other diseases they may have, and E for number of Emergency visits they had in the last 6 months. This list or index is used predict a patients risk of 30-day re admissions, meaning how likely they will need to go back to the hospital.

The items in LACE are different from one another, like roads going north-south compared to roads going east-west. Even though the conditions are different their combination as cross-conditions weave a picture that can be used to make predictions.