How to unify weights in my dataset

I have a symptom-disease network that consists of four attributes: symptom, disease, co-occurrence and TF-IDF. I'm considering the TF-IDF attribute as the weight of my network edges and symptom and disease attributes as nodes of my network. But I think there is a problem that should be addressed. here are some records of my dataset:

MeSH Symptom Term   MeSH Disease Term   PubMed occurrence   TFIDF score
Aging, Premature  Scoliosis           1                   3.46455149
Aging, Premature  HIV Infections      3                   10.39365447
Weight Loss         Scoliosis           1                   1.000053711
Overweight          Scoliosis           1                   0.8238721

As you can see for the disease Scoliosis, for the same co-occurrence we have different TF-IDF scores for different symptoms. Now the question is can I use these TF-IDF scores as weights directly or should I do some unification of weights? Thanks