LCA studies are complicated and also very vulnerable to various assumptions made in the studies. This is why LCAs or WTW studies often show different result. When interpreting results from LCAs it is therefore always important to also try to judge the seriousness and the credabilitiy of the of the study and the partners behind it.
There are standards for how to do “correct” LCAs. An open process with open sources and clear statements of various assumptions of major importance is part of this. A simulation with various major assumptions making LCAs more comparable is also a serious way to work that make outputs more useful and easier to compare.
When interpreting results from LCAs it is therefore always important to also try to judge the seriousness and the credabilitiy of the of the study and the partners behind it.
LCA is mainly a tool for comparisions of alternatives, not a tool to calculate exact values.