Skip to Content

Get to Know ThedaCare’s Newest Providers

Last updated: January 6, 2026

ThedaCare is pleased to introduce our newest providers. Here, we learn what inspires them to improve the health and well-being of our patients, and empower them to live their unique, best lives.

A person with curly brown hair and glasses wears an olive green top against a muted purple-gray backdrop.

Rachael Callahan, PA-C

Physician Assistant, ThedaCare Urgent Care-Appleton and -Neenah

“Listening is at the heart of how I care for patients. My goal is to fully understand each person’s needs and concerns, then explain things in a way that is clear. I want every patient to feel comfortable, informed and actively involved in creating their plan of care.”

A person with blonde hair wears a maroon collared shirt and a necklace with a cross pendant, smiling slightly against a gray-toned background.

Jenifer Grooms, APNP

Nurse Practitioner, ThedaCare Urgent Care-Appleton and -Neenah

“I take a personalized approach to care, focusing on each patient’s unique experience, values and goals. By fostering trust, maintaining open communication and collaborating on care decisions, I empower patients to actively participate in their health journey.”

A person with curly blonde hair wears tortoiseshell glasses and a navy blue collared shirt, smiling directly at the camera against a solid brown background.

Lynda Kasper, MD

Physician, ThedaCare Urgent Care-Appleton

“My approach to care is to provide accurate, timely evaluation and treatment while ensuring patients feel cared for, heard, informed and comfortable throughout their visit. I enjoy working in urgent care because it allows me to meet a wide variety of people, and I can make an immediate, positive impact on their health.”

A young person with dark hair, glasses, and a light blue collared shirt smiles warmly against a muted grayish-brown backdrop.

Saba Khan, DO

Physician, ThedaCare Urgent Care-Appleton and -Neenah

“Every patient has their own story, so I approach each one as a whole person and not just a set of symptoms. I take time to listen, explain things clearly and develop plans that align with their lifestyle, values and what matters most.”                                        

A person with blonde hair and a dark red sweater smiles at the camera, wearing a pearl necklace against a textured gray background.

Michelle Lichtenberg, MSN

Nurse Practitioner, Hospitalist, ThedaCare Medical Center-Berlin

“My approach to care centers on treating each patient as a unique individual, with respect, dignity and compassion. I prioritize actively listening to patients and their families, and I strongly believe in a collaborative, team-based approach to achieve the best possible outcomes.”

A person with light gray/white hair, wearing glasses, a brown collared shirt, and a patterned tie, smiles slightly against a gray-to-brown gradient background.

David Maruska, MD

Family Medicine Physician, ThedaCare Physicians-Oshkosh East

“My approach to care centers on giving patients the tools and knowledge they need to take charge of their well-being. Whether managing a chronic condition or focusing on prevention, I work with each patient to build a care plan that meets their goals.”

A person with long, wavy brown hair wears a black top and a thin silver necklace, smiling slightly at the camera against a gray-brown gradient background.

Allison Senzig, APNP

Nurse Practitioner, ThedaCare Walk-in Care-Shawano

“I love being a nurse practitioner because it allows me to care for patients as individuals and support them through every stage of their health journey. I find it incredibly rewarding to build genuine connections with patients and to know I’m making a positive difference in their lives.”

A person with light brown hair, wearing a black blazer and red top, smiles at the camera against a gray background.

Alexis Vandehey, PharmD

Pharmacist, ThedaCare Cardiovascular Care-Appleton and -Shawano

“By combining compassion with evidence-based clinical support, I aim to provide thoughtful, personalized care that helps each patient feel confident in their treatment plan. I’m passionate about using my expertise in medications to help patients understand their treatment options.”

A person with blonde hair wears a black top and gold necklaces, smiling directly at the camera against a muted brown-gray background.

Carol Voss, MD

Family Medicine Physician, ThedaCare Physicians-Waupaca

“My focus lies on identifying and treating the root causes of health issues, while ensuring patients feel listened to, understood and supported throughout their care. I like working in family medicine because it allows me the opportunity to make a meaningful difference in people’s lives, not just by providing medical care, but by listening to their stories and understanding their experiences.”

A young person with long light brown hair wears a gray blazer over a dark green blouse, smiling at the camera against a muted gray-purple backdrop.

Alyssa Zimmerman, PA-C

Physician Assistant, ThedaCare Medical Center-Waupaca

“My approach to care centers on treating every patient with compassion and respect, recognizing each person’s dignity and providing the highest-quality care possible.”

Tags: January New Providers New Providers

Related Articles

Hands together of doctors and nurses in healthcare teamwork, solidarity and support in hospital diversity. Workflow of medical people, staff or employees in hand stack sign for happy clinic workforce Link to the full post Health Care 101

Get to Know ThedaCare's Newest Providers

Mature Female doctor discussing with man patient at the hospital Link to the full post Cancer Care Health Care 101

Colonoscopy vs. Other Screening Tests: What to Know

Back to site