We know the reasoning and the science behind chemotherapy being used to treat some forms of cancers. We know the survival rate is not 100%, depending on a multitude of factors. We don't simply ignore the people who ended up dying from cancer, as you apparently do with people whose faith beliefs were not answered.
I am at a loss at the statement that I ignore people whose faith beliefs were not answered. Where did I say that? Why do you say that?
We have no information whatsoever about miracle claims, other than the claim itself.
Not true. We know that chemo works because people are healed (albeit not always). We know that faith works because people are healed (albeit not always). Why is it different?
Perhaps you could answer my questions. How does faith cure a medical issue?
Think of it this way. Mind can be stronger than the physical. Many times the very will to live can push normal physical capacity beyond its ability. Maybe you have heard "Now it is up to him and his will to live" - the will, or mind, alters the capacity of the body.
Likewise, the spirit is stronger than both mind and physical. It has the capacity to change the natural course of sickness.
How can we test if faith is indeed what cured the medical condition?
Through empirical evidence. We prayed after the declaration that the woman was going to die in 6 month (or there about -- it's been a while so the exact month count may be off by a month) because of the inoperable tumor and then, after prayer, it shrunk and disappeared and the doctors had no medical explanation.
We prayer for another woman with stage four cancer, and a month later they said "We don't understand it, but it is completely gone". And the list goes on and on.
What is a miracle and how do we know when one has occurred?
A miracle from God, as defined by Christians, is when the natural course of nature is violated. Adrenaline for momentary strength is not a miracle. It is the natural course of nature.
Smith Wigglesworth going to a wake, grabbing a dead person and putting him up on a wall and shouting, "Arise and live" - and on the third time his eyes open and he lives, is called a miracle.
My friend who had a third failure in bridging her broken spinal cord and the doctors said "Don't lift anything over 5lbs, don't have babies, don't do any physical work" and after going to a service, went to her hotel room, fell to the floor crying out to God when she realized all pain was gone and John Hopkins Hospital says, "We have no idea what happened, its a miracle, you spinal cord is completely normal" and two babies later she still is normal and pushes a lawn mower, violates nature and would be classified as a miracle.
What do you even mean when you say "faith?"
I would assume that there are many definitions to try to let the hearer understand. One that I like is:
Hebrews 11:1 Amplified Bible, Classic Edition (AMPC)
11 Now faith is the assurance (the confirmation, the title deed) of the things [we] hope for, being the proof of things [we] do not see
and the conviction of their reality [faith perceiving as real fact what is not revealed to the senses].