Open Web Versus Walled Gardens

NP and PA Influence Is Growing Faster Than Channel Plans

Nurse practitioners (NPs) and physician assistants (PAs) hold prescribing authority, sit at the point of care, and shape treatment decisions in ways that increasingly rival their physician colleagues. Most healthcare marketers accept this. Fewer have updated their channel strategy to match it.

The default answer has been to find the place where this audience gathers professionally. Build a presence inside a clinician network, and the audience comes with it. It is a clean idea, and it is why destination-network pitches remain a fixture of the healthcare professional (HCP) marketing conversation.

HealthLink Dimensions' 2025 NP/PA Communications Report, fielded among 219 NPs and PAs across the United States, suggests the idea has subtly stopped working.

What a Walled Garden Actually Buys You

In healthcare marketing, a walled garden is a platform that sells access to an audience it has enclosed. The clinicians inside registered with that destination, and reaching them means going through it. The model is not illegitimate, and for some campaigns it performs. What it does is set three limits on a program before targeting or creative are ever discussed.

1. Coverage Stops at the Registration List

A network can only offer the clinicians who chose to join it. Any reach figure that follows describes membership, and membership tends to sit well below the size of the market.

Registration is also not the same as active attention. A clinician can hold an account without making that destination a meaningful part of their professional research routine. The more useful questions are how many members are active in a typical month, how often they return, and where they go when they need information about products, devices, or disease states.

On that last question, HealthLink Dimensions’ 2025 survey of 219 U.S. nurse practitioners and physician assistants points toward general medical reference sites, medical journals, specialty associations, and clinical decision-support tools. No professional-only clinician network appeared among the leading research destinations.

Broader HCP research points in the same direction. Physician social networks account for 13% of healthcare professionals’ weekly medical-information time, compared with 26% for dedicated online medical-professional sources and 14% for clinical journal websites. The issue is not whether clinician networks have members. It is whether they command enough active research behavior to function as a primary reach strategy

2. Access Is a Contract, Not an Asset

Audience access inside a walled garden lasts exactly as long as the agreement does. Terms get renegotiated, bundled with adjacent products, re-priced, or restructured at renewal. A brand that has built its NP and PA strategy inside a single destination has tied a core channel to a contract cycle. That is a different category of risk than the one most media plan are built to manage.

3. What You Learn Stays Behind the Wall

Audience definitions, targeting logic, and engagement signals developed inside a closed platform generally do not travel. Change vendors and much of that work restarts from zero. Portable data inverts the relationship: the audience definition becomes an asset the brand owns and carries forward, regardless of which platform runs the next campaign.

The Professional-Only Network Assumption No Longer Holds

Professional-only clinician networks are also losing ground with this audience, and quickly. One leading professional-only network saw reported usage fall from 50% in 2024 to 27% in 2025, a decline of nearly half in a single year. Another peer network registers at 7%. Neither figure describes a channel gaining share of clinician attention.

The more telling finding is the absence.

When NPs and PAs were asked where they go online to research healthcare products, medical devices, and disease state information, they named a consistent short list: consumer-facing clinical reference sites at 46%, medical journals at 44%, specialty association websites at 41%, and point-of-care clinical decision tools at 35%. Manufacturer product websites and general medical databases followed.

That gap separates two things, marketers routinely conflate. A network can hold a clinician's registration without holding their research behavior. Membership is not attention, and attention is what a campaign is actually buying.

Which Channels Do NPs and PAs Actually Respond To?

Email remains the anchor. Seventy-three percent of NPs and PAs name it as a preferred channel for professional communication, and 96% report reviewing work email during downtime. Beyond email, the audience distributes across mainstream platforms rather than professional enclaves: Facebook at 57%, LinkedIn at 49%, Instagram at 44%, and TikTok at 26%.

Digital advertising has moved from peripheral to routine. Two-thirds of NPs and PAs, 67%, report noticing professional advertising online, up from roughly half the year prior. Ninety percent describe themselves as receptive to it, with 34% very receptive. This is an audience that treats well-targeted professional advertising as a legitimate source of education rather than interruption.

Professional attention is distributed across email, mainstream social platforms, and open-web clinical resources. No single destination captures more than a fraction of the audience.

The Ground Is Shifting Under Destination Platforms

Concentrating spend inside one clinician destination assumes professional research stays in predictable places. That assumption is weakening. Referral traffic from AI assistants to brand websites grew 83.7% year over year while paid search referrals fell 22.9%. The change is in how professional audiences locate information, not in what they are looking for.

NPs and PAs are participants in that shift rather than bystanders. Forty percent expect artificial intelligence (AI) to deliver significant benefits to patient care in their practice setting. The most common response in the 2025 survey, and their orientation toward the technology, is pragmatic rather than skeptical.

This has a direct consequence for visibility. When a clinician asks an AI assistant about a therapy, a device, or a disease state, the answer is assembled from sources the model can reach and cite. Material published inside a closed network generally is not among them. Being present and citable across the open web is becoming the durable position. Being resident in one destination is becoming a narrower one.

Reach Should Follow the Audience, Not the Platform

If clinician's attention is distributed and the discovery layer is moving, the data has to be portable. That is the practical consequence of every finding above, and it is the argument for building a verified universe rather than renting access to an enclosed one.

 Profile addresses coverage. HealthLink Dimensions maintains verified records for more than 600,000 NPs and PAs and holds email addresses for 98% of prescribing clinicians, scoped to MDs, DOs, NPs, and PAs. Those addresses are tested monthly for maximum deliverability, so reach reflects current data rather than a snapshot from the last refresh. This is the prescribing universe, not a registration list.

 Engage addresses activation. Audiences built on that foundation deploy into whatever email, programmatic, or paid social environment a brand or agency already uses. There is no inventory to buy into and no platform relationship to protect. The data travels to the channel plan instead of the channel plan bending to the data, and nothing about the audience is at stake when a contract comes up for renewal.

Continuity matters here, too. HealthLink Dimensions has maintained NP and PA prescribing data, specialty demographics, and more for years, through every cycle of interest in this audience. Coverage of the segment Is high and these segments continues to be sone of the most sought-after audiences in the HealthLink Profile.For agency teams building on behalf of multiple clients, portability compounds. One verified NP and PA universe supports campaigns across every client's existing stack.

What a Portable NP and PA Program Looks Like in Practice 

Anchor on email, then reinforce. Cadence preferences cluster tightly, with 31% preferring twice-monthly contact and 30% preferring weekly; early afternoon, between noon and 3 p.m., was the strongest window. Layer digital advertising and mainstream social placements around that spine rather than running them as separate campaigns.

Lead with utility. Product approvals and prescribing updates draw 57%, patient education materials 56%, and continuing medical education (CME) programs 55.5%. Half of respondents cite lack of time as their primary barrier and 48% cite information overload, which argues for short formats, clear subject lines, and a single call to action.

None of this makes peer education worthless. Ambassador programs and clinician communities build real awareness, and that value is not in dispute. The point is narrower: peer recommendations and key opinion leader (KOL) opinions rank at 34% as a prescribing influence, versus 65% for clinical efficacy and safety. Peer programs are a credibility instrument. They are not a reach strategy