The results could lead to better mental health treatment for troops with post traumatic stress disorder, or PTSD.
In the meantime, base officials are preparing for Monday's high-level visit as Secretary of the Army John McHugh comes under a lot of pressure to do something.
Lewis-McChord soldiers complained last year - accusing Madigan Army Medical Center doctors of changing PTSD diagnoses to other conditions that would cost the government less in benefit payouts.
That charge that upsets some military parents.
"That is important that they take care of these guys when they come back," says military parent Tony Scott. "It's not these guys' fault they did their part. The government should do their part."
Soldiers who wanted KOMO News to hide their identities say they think the Army has not done all it can for soldiers returning from combat with mental health issues.
"Listening and open ears to the soldiers - definitely, they do need to work on that," says one career soldier.
He said he is looking forward to hearing what the secretary will say Monday about the investigation into the complaints.
"You can make your speech - you can say anything. But has it happened yet?"
The high-level visit comes as the Pentagon confirmed a tragic reality. More American soldiers died of suicide in 2012 than in combat in Afghanistan. Suicide deaths amounted to 325 troops last year - a record high number.
But some soldiers think the Army is making improvements.
"In the short amount of time I've been here I've seen it change - definitely for the better," says tank crew member James Hong.
Hong thinks commanders have gotten the message and have worked to fix some of the problems with Madigan's behavior health program. He's had mostly positive experiences with base doctors.
"I have no physical ailments - never been injured in my life before. I've been diagnosed with a mental illness, and I'm getting taken care of."