As long as you submit evidence suggesting a link between your claimed condition and service, the VA must assist you in developing the evidence necessary to win your claim. Normally, this means the VA will order a Compensation & Pension Exam (Comp & Pen) to review your file and render a medical opinion as to whether it is as likely as not (50/50) that your claimed condition is related to active duty service and evaluate its severity so the VA can assign a rating between 0% and 100%.