"referral base" is correct and usable in written English.
It can refer to a group of people who have been referred to something. For example, "We have built up our referral base by asking satisfied customers to refer their friends to our business."
The higher proportion of non-paraneoplastic cases in this study compared to the previous report (Dalmau et al., 2008) may reflect the sensitivity of our cell-based assay for serological screening, and the wide referral base of the clinical neuroimmunology service in Oxford, UK.
You're increasing his referral base so he's getting more patients.
"The clinic is a much better model for those communities, because it does provide the referral base.
With Lower Manhattan closed to traffic, the hospital's referral base around the trade center destroyed, and the phones and electricity out, it had almost no patients.
More and more, her business began coming from that referral base, and seven years ago she opened her own business here, Jaan Henry & Company.
Setting: University outpatient setting, rural referral base.
Like most Silicon Valley firms they are referral based.
The problem is most pipelines, they're referral based.
The subsequent negotiation of referral based on patient factors was in turn shaped by the involvement of practitioners.
Included is knowledge of the preparation required for individual procedures, and of the principles of referral based on clinical history and clinical examination.
In addition to the diabetic retinopathy signs detection, the maculopathy detection is also important in order to indicate the urgency of the referral based on the presence or absence of the maculopathy [3].
